From 20c20bd11a0702ce4dc9300c3da58acf551d9725 Mon Sep 17 00:00:00 2001 From: Hou Tao Date: Mon, 4 Dec 2023 22:04:20 +0800 Subject: bpf: Add map and need_defer parameters to .map_fd_put_ptr() map is the pointer of outer map, and need_defer needs some explanation. need_defer tells the implementation to defer the reference release of the passed element and ensure that the element is still alive before the bpf program, which may manipulate it, exits. The following three cases will invoke map_fd_put_ptr() and different need_defer values will be passed to these callers: 1) release the reference of the old element in the map during map update or map deletion. The release must be deferred, otherwise the bpf program may incur use-after-free problem, so need_defer needs to be true. 2) release the reference of the to-be-added element in the error path of map update. The to-be-added element is not visible to any bpf program, so it is OK to pass false for need_defer parameter. 3) release the references of all elements in the map during map release. Any bpf program which has access to the map must have been exited and released, so need_defer=false will be OK. These two parameters will be used by the following patches to fix the potential use-after-free problem for map-in-map. Signed-off-by: Hou Tao Link: https://lore.kernel.org/r/20231204140425.1480317-3-houtao@huaweicloud.com Signed-off-by: Alexei Starovoitov --- kernel/bpf/arraymap.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) (limited to 'kernel/bpf/arraymap.c') diff --git a/kernel/bpf/arraymap.c b/kernel/bpf/arraymap.c index 2058e89b5ddd..f9aed5909d6e 100644 --- a/kernel/bpf/arraymap.c +++ b/kernel/bpf/arraymap.c @@ -867,7 +867,7 @@ int bpf_fd_array_map_update_elem(struct bpf_map *map, struct file *map_file, } if (old_ptr) - map->ops->map_fd_put_ptr(old_ptr); + map->ops->map_fd_put_ptr(map, old_ptr, true); return 0; } @@ -890,7 +890,7 @@ static long fd_array_map_delete_elem(struct bpf_map *map, void *key) } if (old_ptr) { - map->ops->map_fd_put_ptr(old_ptr); + map->ops->map_fd_put_ptr(map, old_ptr, true); return 0; } else { return -ENOENT; @@ -913,8 +913,9 @@ static void *prog_fd_array_get_ptr(struct bpf_map *map, return prog; } -static void prog_fd_array_put_ptr(void *ptr) +static void prog_fd_array_put_ptr(struct bpf_map *map, void *ptr, bool need_defer) { + /* bpf_prog is freed after one RCU or tasks trace grace period */ bpf_prog_put(ptr); } @@ -1239,8 +1240,9 @@ err_out: return ee; } -static void perf_event_fd_array_put_ptr(void *ptr) +static void perf_event_fd_array_put_ptr(struct bpf_map *map, void *ptr, bool need_defer) { + /* bpf_perf_event is freed after one RCU grace period */ bpf_event_entry_free_rcu(ptr); } @@ -1294,7 +1296,7 @@ static void *cgroup_fd_array_get_ptr(struct bpf_map *map, return cgroup_get_from_fd(fd); } -static void cgroup_fd_array_put_ptr(void *ptr) +static void cgroup_fd_array_put_ptr(struct bpf_map *map, void *ptr, bool need_defer) { /* cgroup_put free cgrp after a rcu grace period */ cgroup_put(ptr); -- cgit From 79d93b3c6ffd79abcd8e43345980aa1e904879c4 Mon Sep 17 00:00:00 2001 From: Hou Tao Date: Mon, 4 Dec 2023 22:04:21 +0800 Subject: bpf: Set need_defer as false when clearing fd array during map free Both map deletion operation, map release and map free operation use fd_array_map_delete_elem() to remove the element from fd array and need_defer is always true in fd_array_map_delete_elem(). For the map deletion operation and map release operation, need_defer=true is necessary, because the bpf program, which accesses the element in fd array, may still alive. However for map free operation, it is certain that the bpf program which owns the fd array has already been exited, so setting need_defer as false is appropriate for map free operation. So fix it by adding need_defer parameter to bpf_fd_array_map_clear() and adding a new helper __fd_array_map_delete_elem() to handle the map deletion, map release and map free operations correspondingly. Signed-off-by: Hou Tao Link: https://lore.kernel.org/r/20231204140425.1480317-4-houtao@huaweicloud.com Signed-off-by: Alexei Starovoitov --- kernel/bpf/arraymap.c | 23 ++++++++++++++--------- 1 file changed, 14 insertions(+), 9 deletions(-) (limited to 'kernel/bpf/arraymap.c') diff --git a/kernel/bpf/arraymap.c b/kernel/bpf/arraymap.c index f9aed5909d6e..4a4a67956e21 100644 --- a/kernel/bpf/arraymap.c +++ b/kernel/bpf/arraymap.c @@ -871,7 +871,7 @@ int bpf_fd_array_map_update_elem(struct bpf_map *map, struct file *map_file, return 0; } -static long fd_array_map_delete_elem(struct bpf_map *map, void *key) +static long __fd_array_map_delete_elem(struct bpf_map *map, void *key, bool need_defer) { struct bpf_array *array = container_of(map, struct bpf_array, map); void *old_ptr; @@ -890,13 +890,18 @@ static long fd_array_map_delete_elem(struct bpf_map *map, void *key) } if (old_ptr) { - map->ops->map_fd_put_ptr(map, old_ptr, true); + map->ops->map_fd_put_ptr(map, old_ptr, need_defer); return 0; } else { return -ENOENT; } } +static long fd_array_map_delete_elem(struct bpf_map *map, void *key) +{ + return __fd_array_map_delete_elem(map, key, true); +} + static void *prog_fd_array_get_ptr(struct bpf_map *map, struct file *map_file, int fd) { @@ -925,13 +930,13 @@ static u32 prog_fd_array_sys_lookup_elem(void *ptr) } /* decrement refcnt of all bpf_progs that are stored in this map */ -static void bpf_fd_array_map_clear(struct bpf_map *map) +static void bpf_fd_array_map_clear(struct bpf_map *map, bool need_defer) { struct bpf_array *array = container_of(map, struct bpf_array, map); int i; for (i = 0; i < array->map.max_entries; i++) - fd_array_map_delete_elem(map, &i); + __fd_array_map_delete_elem(map, &i, need_defer); } static void prog_array_map_seq_show_elem(struct bpf_map *map, void *key, @@ -1110,7 +1115,7 @@ static void prog_array_map_clear_deferred(struct work_struct *work) { struct bpf_map *map = container_of(work, struct bpf_array_aux, work)->map; - bpf_fd_array_map_clear(map); + bpf_fd_array_map_clear(map, true); bpf_map_put(map); } @@ -1260,7 +1265,7 @@ static void perf_event_fd_array_release(struct bpf_map *map, for (i = 0; i < array->map.max_entries; i++) { ee = READ_ONCE(array->ptrs[i]); if (ee && ee->map_file == map_file) - fd_array_map_delete_elem(map, &i); + __fd_array_map_delete_elem(map, &i, true); } rcu_read_unlock(); } @@ -1268,7 +1273,7 @@ static void perf_event_fd_array_release(struct bpf_map *map, static void perf_event_fd_array_map_free(struct bpf_map *map) { if (map->map_flags & BPF_F_PRESERVE_ELEMS) - bpf_fd_array_map_clear(map); + bpf_fd_array_map_clear(map, false); fd_array_map_free(map); } @@ -1304,7 +1309,7 @@ static void cgroup_fd_array_put_ptr(struct bpf_map *map, void *ptr, bool need_de static void cgroup_fd_array_free(struct bpf_map *map) { - bpf_fd_array_map_clear(map); + bpf_fd_array_map_clear(map, false); fd_array_map_free(map); } @@ -1349,7 +1354,7 @@ static void array_of_map_free(struct bpf_map *map) * is protected by fdget/fdput. */ bpf_map_meta_free(map->inner_map_meta); - bpf_fd_array_map_clear(map); + bpf_fd_array_map_clear(map, false); fd_array_map_free(map); } -- cgit From 8062fb12de99b2da33754c6a3be1bfc30d9a35f4 Mon Sep 17 00:00:00 2001 From: Andrii Nakryiko Date: Thu, 30 Nov 2023 10:52:20 -0800 Subject: bpf: consistently use BPF token throughout BPF verifier logic Remove remaining direct queries to perfmon_capable() and bpf_capable() in BPF verifier logic and instead use BPF token (if available) to make decisions about privileges. Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/r/20231130185229.2688956-9-andrii@kernel.org Signed-off-by: Alexei Starovoitov --- include/linux/bpf.h | 16 ++++++++-------- include/linux/filter.h | 2 +- kernel/bpf/arraymap.c | 2 +- kernel/bpf/core.c | 2 +- kernel/bpf/verifier.c | 13 ++++++------- net/core/filter.c | 4 ++-- 6 files changed, 19 insertions(+), 20 deletions(-) (limited to 'kernel/bpf/arraymap.c') diff --git a/include/linux/bpf.h b/include/linux/bpf.h index 2a3ab4f3dd8c..435abad3cc61 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -2200,24 +2200,24 @@ extern int sysctl_unprivileged_bpf_disabled; bool bpf_token_capable(const struct bpf_token *token, int cap); -static inline bool bpf_allow_ptr_leaks(void) +static inline bool bpf_allow_ptr_leaks(const struct bpf_token *token) { - return perfmon_capable(); + return bpf_token_capable(token, CAP_PERFMON); } -static inline bool bpf_allow_uninit_stack(void) +static inline bool bpf_allow_uninit_stack(const struct bpf_token *token) { - return perfmon_capable(); + return bpf_token_capable(token, CAP_PERFMON); } -static inline bool bpf_bypass_spec_v1(void) +static inline bool bpf_bypass_spec_v1(const struct bpf_token *token) { - return cpu_mitigations_off() || perfmon_capable(); + return cpu_mitigations_off() || bpf_token_capable(token, CAP_PERFMON); } -static inline bool bpf_bypass_spec_v4(void) +static inline bool bpf_bypass_spec_v4(const struct bpf_token *token) { - return cpu_mitigations_off() || perfmon_capable(); + return cpu_mitigations_off() || bpf_token_capable(token, CAP_PERFMON); } int bpf_map_new_fd(struct bpf_map *map, int flags); diff --git a/include/linux/filter.h b/include/linux/filter.h index a4953fafc8cb..14354605ad26 100644 --- a/include/linux/filter.h +++ b/include/linux/filter.h @@ -1139,7 +1139,7 @@ static inline bool bpf_jit_blinding_enabled(struct bpf_prog *prog) return false; if (!bpf_jit_harden) return false; - if (bpf_jit_harden == 1 && bpf_capable()) + if (bpf_jit_harden == 1 && bpf_token_capable(prog->aux->token, CAP_BPF)) return false; return true; diff --git a/kernel/bpf/arraymap.c b/kernel/bpf/arraymap.c index 4a4a67956e21..8d365bda9a8b 100644 --- a/kernel/bpf/arraymap.c +++ b/kernel/bpf/arraymap.c @@ -82,7 +82,7 @@ static struct bpf_map *array_map_alloc(union bpf_attr *attr) bool percpu = attr->map_type == BPF_MAP_TYPE_PERCPU_ARRAY; int numa_node = bpf_map_attr_numa_node(attr); u32 elem_size, index_mask, max_entries; - bool bypass_spec_v1 = bpf_bypass_spec_v1(); + bool bypass_spec_v1 = bpf_bypass_spec_v1(NULL); u64 array_size, mask64; struct bpf_array *array; diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c index 47085839af8d..ced511f44174 100644 --- a/kernel/bpf/core.c +++ b/kernel/bpf/core.c @@ -675,7 +675,7 @@ static bool bpf_prog_kallsyms_candidate(const struct bpf_prog *fp) void bpf_prog_kallsyms_add(struct bpf_prog *fp) { if (!bpf_prog_kallsyms_candidate(fp) || - !bpf_capable()) + !bpf_token_capable(fp->aux->token, CAP_BPF)) return; bpf_prog_ksym_set_addr(fp); diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index e5ce530641ba..45e85fb76d82 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -20597,7 +20597,12 @@ int bpf_check(struct bpf_prog **prog, union bpf_attr *attr, bpfptr_t uattr, __u3 env->prog = *prog; env->ops = bpf_verifier_ops[env->prog->type]; env->fd_array = make_bpfptr(attr->fd_array, uattr.is_kernel); - is_priv = bpf_capable(); + + env->allow_ptr_leaks = bpf_allow_ptr_leaks(env->prog->aux->token); + env->allow_uninit_stack = bpf_allow_uninit_stack(env->prog->aux->token); + env->bypass_spec_v1 = bpf_bypass_spec_v1(env->prog->aux->token); + env->bypass_spec_v4 = bpf_bypass_spec_v4(env->prog->aux->token); + env->bpf_capable = is_priv = bpf_token_capable(env->prog->aux->token, CAP_BPF); bpf_get_btf_vmlinux(); @@ -20629,12 +20634,6 @@ int bpf_check(struct bpf_prog **prog, union bpf_attr *attr, bpfptr_t uattr, __u3 if (attr->prog_flags & BPF_F_ANY_ALIGNMENT) env->strict_alignment = false; - env->allow_ptr_leaks = bpf_allow_ptr_leaks(); - env->allow_uninit_stack = bpf_allow_uninit_stack(); - env->bypass_spec_v1 = bpf_bypass_spec_v1(); - env->bypass_spec_v4 = bpf_bypass_spec_v4(); - env->bpf_capable = bpf_capable(); - if (is_priv) env->test_state_freq = attr->prog_flags & BPF_F_TEST_STATE_FREQ; env->test_reg_invariants = attr->prog_flags & BPF_F_TEST_REG_INVARIANTS; diff --git a/net/core/filter.c b/net/core/filter.c index 0bf2a03d8203..adcfc2c25754 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -8559,7 +8559,7 @@ static bool cg_skb_is_valid_access(int off, int size, return false; case bpf_ctx_range(struct __sk_buff, data): case bpf_ctx_range(struct __sk_buff, data_end): - if (!bpf_capable()) + if (!bpf_token_capable(prog->aux->token, CAP_BPF)) return false; break; } @@ -8571,7 +8571,7 @@ static bool cg_skb_is_valid_access(int off, int size, case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]): break; case bpf_ctx_range(struct __sk_buff, tstamp): - if (!bpf_capable()) + if (!bpf_token_capable(prog->aux->token, CAP_BPF)) return false; break; default: -- cgit From 4b7de801606e504e69689df71475d27e35336fb3 Mon Sep 17 00:00:00 2001 From: Jiri Olsa Date: Wed, 6 Dec 2023 09:30:40 +0100 Subject: bpf: Fix prog_array_map_poke_run map poke update Lee pointed out issue found by syscaller [0] hitting BUG in prog array map poke update in prog_array_map_poke_run function due to error value returned from bpf_arch_text_poke function. There's race window where bpf_arch_text_poke can fail due to missing bpf program kallsym symbols, which is accounted for with check for -EINVAL in that BUG_ON call. The problem is that in such case we won't update the tail call jump and cause imbalance for the next tail call update check which will fail with -EBUSY in bpf_arch_text_poke. I'm hitting following race during the program load: CPU 0 CPU 1 bpf_prog_load bpf_check do_misc_fixups prog_array_map_poke_track map_update_elem bpf_fd_array_map_update_elem prog_array_map_poke_run bpf_arch_text_poke returns -EINVAL bpf_prog_kallsyms_add After bpf_arch_text_poke (CPU 1) fails to update the tail call jump, the next poke update fails on expected jump instruction check in bpf_arch_text_poke with -EBUSY and triggers the BUG_ON in prog_array_map_poke_run. Similar race exists on the program unload. Fixing this by moving the update to bpf_arch_poke_desc_update function which makes sure we call __bpf_arch_text_poke that skips the bpf address check. Each architecture has slightly different approach wrt looking up bpf address in bpf_arch_text_poke, so instead of splitting the function or adding new 'checkip' argument in previous version, it seems best to move the whole map_poke_run update as arch specific code. [0] https://syzkaller.appspot.com/bug?extid=97a4fe20470e9bc30810 Fixes: ebf7d1f508a7 ("bpf, x64: rework pro/epilogue and tailcall handling in JIT") Reported-by: syzbot+97a4fe20470e9bc30810@syzkaller.appspotmail.com Signed-off-by: Jiri Olsa Signed-off-by: Daniel Borkmann Acked-by: Yonghong Song Cc: Lee Jones Cc: Maciej Fijalkowski Link: https://lore.kernel.org/bpf/20231206083041.1306660-2-jolsa@kernel.org --- arch/x86/net/bpf_jit_comp.c | 46 +++++++++++++++++++++++++++++++++++ include/linux/bpf.h | 3 +++ kernel/bpf/arraymap.c | 58 ++++++++------------------------------------- 3 files changed, 59 insertions(+), 48 deletions(-) (limited to 'kernel/bpf/arraymap.c') diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c index 8c10d9abc239..e89e415aa743 100644 --- a/arch/x86/net/bpf_jit_comp.c +++ b/arch/x86/net/bpf_jit_comp.c @@ -3025,3 +3025,49 @@ void arch_bpf_stack_walk(bool (*consume_fn)(void *cookie, u64 ip, u64 sp, u64 bp #endif WARN(1, "verification of programs using bpf_throw should have failed\n"); } + +void bpf_arch_poke_desc_update(struct bpf_jit_poke_descriptor *poke, + struct bpf_prog *new, struct bpf_prog *old) +{ + u8 *old_addr, *new_addr, *old_bypass_addr; + int ret; + + old_bypass_addr = old ? NULL : poke->bypass_addr; + old_addr = old ? (u8 *)old->bpf_func + poke->adj_off : NULL; + new_addr = new ? (u8 *)new->bpf_func + poke->adj_off : NULL; + + /* + * On program loading or teardown, the program's kallsym entry + * might not be in place, so we use __bpf_arch_text_poke to skip + * the kallsyms check. + */ + if (new) { + ret = __bpf_arch_text_poke(poke->tailcall_target, + BPF_MOD_JUMP, + old_addr, new_addr); + BUG_ON(ret < 0); + if (!old) { + ret = __bpf_arch_text_poke(poke->tailcall_bypass, + BPF_MOD_JUMP, + poke->bypass_addr, + NULL); + BUG_ON(ret < 0); + } + } else { + ret = __bpf_arch_text_poke(poke->tailcall_bypass, + BPF_MOD_JUMP, + old_bypass_addr, + poke->bypass_addr); + BUG_ON(ret < 0); + /* let other CPUs finish the execution of program + * so that it will not possible to expose them + * to invalid nop, stack unwind, nop state + */ + if (!ret) + synchronize_rcu(); + ret = __bpf_arch_text_poke(poke->tailcall_target, + BPF_MOD_JUMP, + old_addr, NULL); + BUG_ON(ret < 0); + } +} diff --git a/include/linux/bpf.h b/include/linux/bpf.h index 6762dac3ef76..cff5bb08820e 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -3175,6 +3175,9 @@ enum bpf_text_poke_type { int bpf_arch_text_poke(void *ip, enum bpf_text_poke_type t, void *addr1, void *addr2); +void bpf_arch_poke_desc_update(struct bpf_jit_poke_descriptor *poke, + struct bpf_prog *new, struct bpf_prog *old); + void *bpf_arch_text_copy(void *dst, void *src, size_t len); int bpf_arch_text_invalidate(void *dst, size_t len); diff --git a/kernel/bpf/arraymap.c b/kernel/bpf/arraymap.c index 2058e89b5ddd..c85ff9162a5c 100644 --- a/kernel/bpf/arraymap.c +++ b/kernel/bpf/arraymap.c @@ -1012,11 +1012,16 @@ static void prog_array_map_poke_untrack(struct bpf_map *map, mutex_unlock(&aux->poke_mutex); } +void __weak bpf_arch_poke_desc_update(struct bpf_jit_poke_descriptor *poke, + struct bpf_prog *new, struct bpf_prog *old) +{ + WARN_ON_ONCE(1); +} + static void prog_array_map_poke_run(struct bpf_map *map, u32 key, struct bpf_prog *old, struct bpf_prog *new) { - u8 *old_addr, *new_addr, *old_bypass_addr; struct prog_poke_elem *elem; struct bpf_array_aux *aux; @@ -1025,7 +1030,7 @@ static void prog_array_map_poke_run(struct bpf_map *map, u32 key, list_for_each_entry(elem, &aux->poke_progs, list) { struct bpf_jit_poke_descriptor *poke; - int i, ret; + int i; for (i = 0; i < elem->aux->size_poke_tab; i++) { poke = &elem->aux->poke_tab[i]; @@ -1044,21 +1049,10 @@ static void prog_array_map_poke_run(struct bpf_map *map, u32 key, * activated, so tail call updates can arrive from here * while JIT is still finishing its final fixup for * non-activated poke entries. - * 3) On program teardown, the program's kallsym entry gets - * removed out of RCU callback, but we can only untrack - * from sleepable context, therefore bpf_arch_text_poke() - * might not see that this is in BPF text section and - * bails out with -EINVAL. As these are unreachable since - * RCU grace period already passed, we simply skip them. - * 4) Also programs reaching refcount of zero while patching + * 3) Also programs reaching refcount of zero while patching * is in progress is okay since we're protected under * poke_mutex and untrack the programs before the JIT - * buffer is freed. When we're still in the middle of - * patching and suddenly kallsyms entry of the program - * gets evicted, we just skip the rest which is fine due - * to point 3). - * 5) Any other error happening below from bpf_arch_text_poke() - * is a unexpected bug. + * buffer is freed. */ if (!READ_ONCE(poke->tailcall_target_stable)) continue; @@ -1068,39 +1062,7 @@ static void prog_array_map_poke_run(struct bpf_map *map, u32 key, poke->tail_call.key != key) continue; - old_bypass_addr = old ? NULL : poke->bypass_addr; - old_addr = old ? (u8 *)old->bpf_func + poke->adj_off : NULL; - new_addr = new ? (u8 *)new->bpf_func + poke->adj_off : NULL; - - if (new) { - ret = bpf_arch_text_poke(poke->tailcall_target, - BPF_MOD_JUMP, - old_addr, new_addr); - BUG_ON(ret < 0 && ret != -EINVAL); - if (!old) { - ret = bpf_arch_text_poke(poke->tailcall_bypass, - BPF_MOD_JUMP, - poke->bypass_addr, - NULL); - BUG_ON(ret < 0 && ret != -EINVAL); - } - } else { - ret = bpf_arch_text_poke(poke->tailcall_bypass, - BPF_MOD_JUMP, - old_bypass_addr, - poke->bypass_addr); - BUG_ON(ret < 0 && ret != -EINVAL); - /* let other CPUs finish the execution of program - * so that it will not possible to expose them - * to invalid nop, stack unwind, nop state - */ - if (!ret) - synchronize_rcu(); - ret = bpf_arch_text_poke(poke->tailcall_target, - BPF_MOD_JUMP, - old_addr, NULL); - BUG_ON(ret < 0 && ret != -EINVAL); - } + bpf_arch_poke_desc_update(poke, new, old); } } } -- cgit From dc68540913ac523b46ebda3843cec179362c7a72 Mon Sep 17 00:00:00 2001 From: Hou Tao Date: Thu, 14 Dec 2023 12:30:10 +0800 Subject: bpf: Use GFP_KERNEL in bpf_event_entry_gen() rcu_read_lock() is no longer held when invoking bpf_event_entry_gen() which is called by perf_event_fd_array_get_ptr(), so using GFP_KERNEL instead of GFP_ATOMIC to reduce the possibility of failures due to out-of-memory. Acked-by: Yonghong Song Signed-off-by: Hou Tao Link: https://lore.kernel.org/r/20231214043010.3458072-3-houtao@huaweicloud.com Signed-off-by: Alexei Starovoitov --- kernel/bpf/arraymap.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'kernel/bpf/arraymap.c') diff --git a/kernel/bpf/arraymap.c b/kernel/bpf/arraymap.c index 8d365bda9a8b..b5ec24b3563e 100644 --- a/kernel/bpf/arraymap.c +++ b/kernel/bpf/arraymap.c @@ -1195,7 +1195,7 @@ static struct bpf_event_entry *bpf_event_entry_gen(struct file *perf_file, { struct bpf_event_entry *ee; - ee = kzalloc(sizeof(*ee), GFP_ATOMIC); + ee = kzalloc(sizeof(*ee), GFP_KERNEL); if (ee) { ee->event = perf_file->private_data; ee->perf_file = perf_file; -- cgit From d17aff807f845cf93926c28705216639c7279110 Mon Sep 17 00:00:00 2001 From: Andrii Nakryiko Date: Tue, 19 Dec 2023 07:37:35 -0800 Subject: Revert BPF token-related functionality This patch includes the following revert (one conflicting BPF FS patch and three token patch sets, represented by merge commits): - revert 0f5d5454c723 "Merge branch 'bpf-fs-mount-options-parsing-follow-ups'"; - revert 750e785796bb "bpf: Support uid and gid when mounting bpffs"; - revert 733763285acf "Merge branch 'bpf-token-support-in-libbpf-s-bpf-object'"; - revert c35919dcce28 "Merge branch 'bpf-token-and-bpf-fs-based-delegation'". Link: https://lore.kernel.org/bpf/CAHk-=wg7JuFYwGy=GOMbRCtOL+jwSQsdUaBsRWkDVYbxipbM5A@mail.gmail.com Signed-off-by: Andrii Nakryiko --- drivers/media/rc/bpf-lirc.c | 2 +- include/linux/bpf.h | 85 +- include/linux/filter.h | 2 +- include/linux/lsm_hook_defs.h | 15 +- include/linux/security.h | 43 +- include/uapi/linux/bpf.h | 42 - kernel/bpf/Makefile | 2 +- kernel/bpf/arraymap.c | 2 +- kernel/bpf/bpf_lsm.c | 15 +- kernel/bpf/cgroup.c | 6 +- kernel/bpf/core.c | 3 +- kernel/bpf/helpers.c | 6 +- kernel/bpf/inode.c | 326 +------ kernel/bpf/syscall.c | 215 ++-- kernel/bpf/token.c | 271 ----- kernel/bpf/verifier.c | 13 +- kernel/trace/bpf_trace.c | 2 +- net/core/filter.c | 36 +- net/ipv4/bpf_tcp_ca.c | 2 +- net/netfilter/nf_bpf_link.c | 2 +- security/security.c | 101 +- security/selinux/hooks.c | 47 +- tools/include/uapi/linux/bpf.h | 42 - tools/lib/bpf/Build | 2 +- tools/lib/bpf/bpf.c | 37 +- tools/lib/bpf/bpf.h | 35 +- tools/lib/bpf/btf.c | 7 +- tools/lib/bpf/elf.c | 2 + tools/lib/bpf/features.c | 478 --------- tools/lib/bpf/libbpf.c | 573 ++++++++--- tools/lib/bpf/libbpf.h | 37 +- tools/lib/bpf/libbpf.map | 1 - tools/lib/bpf/libbpf_internal.h | 36 +- tools/lib/bpf/libbpf_probes.c | 8 +- tools/lib/bpf/str_error.h | 3 - .../selftests/bpf/prog_tests/libbpf_probes.c | 4 - .../testing/selftests/bpf/prog_tests/libbpf_str.c | 6 - tools/testing/selftests/bpf/prog_tests/token.c | 1031 -------------------- tools/testing/selftests/bpf/progs/priv_map.c | 13 - tools/testing/selftests/bpf/progs/priv_prog.c | 13 - 40 files changed, 641 insertions(+), 2925 deletions(-) delete mode 100644 kernel/bpf/token.c delete mode 100644 tools/lib/bpf/features.c delete mode 100644 tools/testing/selftests/bpf/prog_tests/token.c delete mode 100644 tools/testing/selftests/bpf/progs/priv_map.c delete mode 100644 tools/testing/selftests/bpf/progs/priv_prog.c (limited to 'kernel/bpf/arraymap.c') diff --git a/drivers/media/rc/bpf-lirc.c b/drivers/media/rc/bpf-lirc.c index 6d07693c6b9f..fe17c7f98e81 100644 --- a/drivers/media/rc/bpf-lirc.c +++ b/drivers/media/rc/bpf-lirc.c @@ -110,7 +110,7 @@ lirc_mode2_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) case BPF_FUNC_get_prandom_u32: return &bpf_get_prandom_u32_proto; case BPF_FUNC_trace_printk: - if (bpf_token_capable(prog->aux->token, CAP_PERFMON)) + if (perfmon_capable()) return bpf_get_trace_printk_proto(); fallthrough; default: diff --git a/include/linux/bpf.h b/include/linux/bpf.h index 2f54cc0436c4..7a8d4c81a39a 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -52,10 +52,6 @@ struct module; struct bpf_func_state; struct ftrace_ops; struct cgroup; -struct bpf_token; -struct user_namespace; -struct super_block; -struct inode; extern struct idr btf_idr; extern spinlock_t btf_idr_lock; @@ -1488,7 +1484,6 @@ struct bpf_prog_aux { #ifdef CONFIG_SECURITY void *security; #endif - struct bpf_token *token; struct bpf_prog_offload *offload; struct btf *btf; struct bpf_func_info *func_info; @@ -1613,31 +1608,6 @@ struct bpf_link_primer { u32 id; }; -struct bpf_mount_opts { - kuid_t uid; - kgid_t gid; - umode_t mode; - - /* BPF token-related delegation options */ - u64 delegate_cmds; - u64 delegate_maps; - u64 delegate_progs; - u64 delegate_attachs; -}; - -struct bpf_token { - struct work_struct work; - atomic64_t refcnt; - struct user_namespace *userns; - u64 allowed_cmds; - u64 allowed_maps; - u64 allowed_progs; - u64 allowed_attachs; -#ifdef CONFIG_SECURITY - void *security; -#endif -}; - struct bpf_struct_ops_value; struct btf_member; @@ -2097,7 +2067,6 @@ static inline void bpf_enable_instrumentation(void) migrate_enable(); } -extern const struct super_operations bpf_super_ops; extern const struct file_operations bpf_map_fops; extern const struct file_operations bpf_prog_fops; extern const struct file_operations bpf_iter_fops; @@ -2232,26 +2201,24 @@ static inline void bpf_map_dec_elem_count(struct bpf_map *map) extern int sysctl_unprivileged_bpf_disabled; -bool bpf_token_capable(const struct bpf_token *token, int cap); - -static inline bool bpf_allow_ptr_leaks(const struct bpf_token *token) +static inline bool bpf_allow_ptr_leaks(void) { - return bpf_token_capable(token, CAP_PERFMON); + return perfmon_capable(); } -static inline bool bpf_allow_uninit_stack(const struct bpf_token *token) +static inline bool bpf_allow_uninit_stack(void) { - return bpf_token_capable(token, CAP_PERFMON); + return perfmon_capable(); } -static inline bool bpf_bypass_spec_v1(const struct bpf_token *token) +static inline bool bpf_bypass_spec_v1(void) { - return cpu_mitigations_off() || bpf_token_capable(token, CAP_PERFMON); + return cpu_mitigations_off() || perfmon_capable(); } -static inline bool bpf_bypass_spec_v4(const struct bpf_token *token) +static inline bool bpf_bypass_spec_v4(void) { - return cpu_mitigations_off() || bpf_token_capable(token, CAP_PERFMON); + return cpu_mitigations_off() || perfmon_capable(); } int bpf_map_new_fd(struct bpf_map *map, int flags); @@ -2268,21 +2235,8 @@ int bpf_link_new_fd(struct bpf_link *link); struct bpf_link *bpf_link_get_from_fd(u32 ufd); struct bpf_link *bpf_link_get_curr_or_next(u32 *id); -void bpf_token_inc(struct bpf_token *token); -void bpf_token_put(struct bpf_token *token); -int bpf_token_create(union bpf_attr *attr); -struct bpf_token *bpf_token_get_from_fd(u32 ufd); - -bool bpf_token_allow_cmd(const struct bpf_token *token, enum bpf_cmd cmd); -bool bpf_token_allow_map_type(const struct bpf_token *token, enum bpf_map_type type); -bool bpf_token_allow_prog_type(const struct bpf_token *token, - enum bpf_prog_type prog_type, - enum bpf_attach_type attach_type); - int bpf_obj_pin_user(u32 ufd, int path_fd, const char __user *pathname); int bpf_obj_get_user(int path_fd, const char __user *pathname, int flags); -struct inode *bpf_get_inode(struct super_block *sb, const struct inode *dir, - umode_t mode); #define BPF_ITER_FUNC_PREFIX "bpf_iter_" #define DEFINE_BPF_ITER_FUNC(target, args...) \ @@ -2526,8 +2480,7 @@ const char *btf_find_decl_tag_value(const struct btf *btf, const struct btf_type struct bpf_prog *bpf_prog_by_id(u32 id); struct bpf_link *bpf_link_by_id(u32 id); -const struct bpf_func_proto *bpf_base_func_proto(enum bpf_func_id func_id, - const struct bpf_prog *prog); +const struct bpf_func_proto *bpf_base_func_proto(enum bpf_func_id func_id); void bpf_task_storage_free(struct task_struct *task); void bpf_cgrp_storage_free(struct cgroup *cgroup); bool bpf_prog_has_kfunc_call(const struct bpf_prog *prog); @@ -2646,24 +2599,6 @@ static inline int bpf_obj_get_user(const char __user *pathname, int flags) return -EOPNOTSUPP; } -static inline bool bpf_token_capable(const struct bpf_token *token, int cap) -{ - return capable(cap) || (cap != CAP_SYS_ADMIN && capable(CAP_SYS_ADMIN)); -} - -static inline void bpf_token_inc(struct bpf_token *token) -{ -} - -static inline void bpf_token_put(struct bpf_token *token) -{ -} - -static inline struct bpf_token *bpf_token_get_from_fd(u32 ufd) -{ - return ERR_PTR(-EOPNOTSUPP); -} - static inline void __dev_flush(void) { } @@ -2787,7 +2722,7 @@ static inline int btf_struct_access(struct bpf_verifier_log *log, } static inline const struct bpf_func_proto * -bpf_base_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) +bpf_base_func_proto(enum bpf_func_id func_id) { return NULL; } diff --git a/include/linux/filter.h b/include/linux/filter.h index 12d907f17d36..68fb6c8142fe 100644 --- a/include/linux/filter.h +++ b/include/linux/filter.h @@ -1139,7 +1139,7 @@ static inline bool bpf_jit_blinding_enabled(struct bpf_prog *prog) return false; if (!bpf_jit_harden) return false; - if (bpf_jit_harden == 1 && bpf_token_capable(prog->aux->token, CAP_BPF)) + if (bpf_jit_harden == 1 && bpf_capable()) return false; return true; diff --git a/include/linux/lsm_hook_defs.h b/include/linux/lsm_hook_defs.h index 3fdd00b452ac..ff217a5ce552 100644 --- a/include/linux/lsm_hook_defs.h +++ b/include/linux/lsm_hook_defs.h @@ -398,17 +398,10 @@ LSM_HOOK(void, LSM_RET_VOID, audit_rule_free, void *lsmrule) LSM_HOOK(int, 0, bpf, int cmd, union bpf_attr *attr, unsigned int size) LSM_HOOK(int, 0, bpf_map, struct bpf_map *map, fmode_t fmode) LSM_HOOK(int, 0, bpf_prog, struct bpf_prog *prog) -LSM_HOOK(int, 0, bpf_map_create, struct bpf_map *map, union bpf_attr *attr, - struct bpf_token *token) -LSM_HOOK(void, LSM_RET_VOID, bpf_map_free, struct bpf_map *map) -LSM_HOOK(int, 0, bpf_prog_load, struct bpf_prog *prog, union bpf_attr *attr, - struct bpf_token *token) -LSM_HOOK(void, LSM_RET_VOID, bpf_prog_free, struct bpf_prog *prog) -LSM_HOOK(int, 0, bpf_token_create, struct bpf_token *token, union bpf_attr *attr, - struct path *path) -LSM_HOOK(void, LSM_RET_VOID, bpf_token_free, struct bpf_token *token) -LSM_HOOK(int, 0, bpf_token_cmd, const struct bpf_token *token, enum bpf_cmd cmd) -LSM_HOOK(int, 0, bpf_token_capable, const struct bpf_token *token, int cap) +LSM_HOOK(int, 0, bpf_map_alloc_security, struct bpf_map *map) +LSM_HOOK(void, LSM_RET_VOID, bpf_map_free_security, struct bpf_map *map) +LSM_HOOK(int, 0, bpf_prog_alloc_security, struct bpf_prog_aux *aux) +LSM_HOOK(void, LSM_RET_VOID, bpf_prog_free_security, struct bpf_prog_aux *aux) #endif /* CONFIG_BPF_SYSCALL */ LSM_HOOK(int, 0, locked_down, enum lockdown_reason what) diff --git a/include/linux/security.h b/include/linux/security.h index 00809d2d5c38..1d1df326c881 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -32,7 +32,6 @@ #include #include #include -#include struct linux_binprm; struct cred; @@ -2021,22 +2020,15 @@ static inline void securityfs_remove(struct dentry *dentry) union bpf_attr; struct bpf_map; struct bpf_prog; -struct bpf_token; +struct bpf_prog_aux; #ifdef CONFIG_SECURITY extern int security_bpf(int cmd, union bpf_attr *attr, unsigned int size); extern int security_bpf_map(struct bpf_map *map, fmode_t fmode); extern int security_bpf_prog(struct bpf_prog *prog); -extern int security_bpf_map_create(struct bpf_map *map, union bpf_attr *attr, - struct bpf_token *token); +extern int security_bpf_map_alloc(struct bpf_map *map); extern void security_bpf_map_free(struct bpf_map *map); -extern int security_bpf_prog_load(struct bpf_prog *prog, union bpf_attr *attr, - struct bpf_token *token); -extern void security_bpf_prog_free(struct bpf_prog *prog); -extern int security_bpf_token_create(struct bpf_token *token, union bpf_attr *attr, - struct path *path); -extern void security_bpf_token_free(struct bpf_token *token); -extern int security_bpf_token_cmd(const struct bpf_token *token, enum bpf_cmd cmd); -extern int security_bpf_token_capable(const struct bpf_token *token, int cap); +extern int security_bpf_prog_alloc(struct bpf_prog_aux *aux); +extern void security_bpf_prog_free(struct bpf_prog_aux *aux); #else static inline int security_bpf(int cmd, union bpf_attr *attr, unsigned int size) @@ -2054,8 +2046,7 @@ static inline int security_bpf_prog(struct bpf_prog *prog) return 0; } -static inline int security_bpf_map_create(struct bpf_map *map, union bpf_attr *attr, - struct bpf_token *token) +static inline int security_bpf_map_alloc(struct bpf_map *map) { return 0; } @@ -2063,33 +2054,13 @@ static inline int security_bpf_map_create(struct bpf_map *map, union bpf_attr *a static inline void security_bpf_map_free(struct bpf_map *map) { } -static inline int security_bpf_prog_load(struct bpf_prog *prog, union bpf_attr *attr, - struct bpf_token *token) +static inline int security_bpf_prog_alloc(struct bpf_prog_aux *aux) { return 0; } -static inline void security_bpf_prog_free(struct bpf_prog *prog) +static inline void security_bpf_prog_free(struct bpf_prog_aux *aux) { } - -static inline int security_bpf_token_create(struct bpf_token *token, union bpf_attr *attr, - struct path *path) -{ - return 0; -} - -static inline void security_bpf_token_free(struct bpf_token *token) -{ } - -static inline int security_bpf_token_cmd(const struct bpf_token *token, enum bpf_cmd cmd) -{ - return 0; -} - -static inline int security_bpf_token_capable(const struct bpf_token *token, int cap) -{ - return 0; -} #endif /* CONFIG_SECURITY */ #endif /* CONFIG_BPF_SYSCALL */ diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index 42f4d3090efe..754e68ca8744 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -847,36 +847,6 @@ union bpf_iter_link_info { * Returns zero on success. On error, -1 is returned and *errno* * is set appropriately. * - * BPF_TOKEN_CREATE - * Description - * Create BPF token with embedded information about what - * BPF-related functionality it allows: - * - a set of allowed bpf() syscall commands; - * - a set of allowed BPF map types to be created with - * BPF_MAP_CREATE command, if BPF_MAP_CREATE itself is allowed; - * - a set of allowed BPF program types and BPF program attach - * types to be loaded with BPF_PROG_LOAD command, if - * BPF_PROG_LOAD itself is allowed. - * - * BPF token is created (derived) from an instance of BPF FS, - * assuming it has necessary delegation mount options specified. - * This BPF token can be passed as an extra parameter to various - * bpf() syscall commands to grant BPF subsystem functionality to - * unprivileged processes. - * - * When created, BPF token is "associated" with the owning - * user namespace of BPF FS instance (super block) that it was - * derived from, and subsequent BPF operations performed with - * BPF token would be performing capabilities checks (i.e., - * CAP_BPF, CAP_PERFMON, CAP_NET_ADMIN, CAP_SYS_ADMIN) within - * that user namespace. Without BPF token, such capabilities - * have to be granted in init user namespace, making bpf() - * syscall incompatible with user namespace, for the most part. - * - * Return - * A new file descriptor (a nonnegative integer), or -1 if an - * error occurred (in which case, *errno* is set appropriately). - * * NOTES * eBPF objects (maps and programs) can be shared between processes. * @@ -931,8 +901,6 @@ enum bpf_cmd { BPF_ITER_CREATE, BPF_LINK_DETACH, BPF_PROG_BIND_MAP, - BPF_TOKEN_CREATE, - __MAX_BPF_CMD, }; enum bpf_map_type { @@ -983,7 +951,6 @@ enum bpf_map_type { BPF_MAP_TYPE_BLOOM_FILTER, BPF_MAP_TYPE_USER_RINGBUF, BPF_MAP_TYPE_CGRP_STORAGE, - __MAX_BPF_MAP_TYPE }; /* Note that tracing related programs such as @@ -1028,7 +995,6 @@ enum bpf_prog_type { BPF_PROG_TYPE_SK_LOOKUP, BPF_PROG_TYPE_SYSCALL, /* a program that can execute syscalls */ BPF_PROG_TYPE_NETFILTER, - __MAX_BPF_PROG_TYPE }; enum bpf_attach_type { @@ -1437,7 +1403,6 @@ union bpf_attr { * to using 5 hash functions). */ __u64 map_extra; - __u32 map_token_fd; }; struct { /* anonymous struct used by BPF_MAP_*_ELEM commands */ @@ -1507,7 +1472,6 @@ union bpf_attr { * truncated), or smaller (if log buffer wasn't filled completely). */ __u32 log_true_size; - __u32 prog_token_fd; }; struct { /* anonymous struct used by BPF_OBJ_* commands */ @@ -1620,7 +1584,6 @@ union bpf_attr { * truncated), or smaller (if log buffer wasn't filled completely). */ __u32 btf_log_true_size; - __u32 btf_token_fd; }; struct { @@ -1751,11 +1714,6 @@ union bpf_attr { __u32 flags; /* extra flags */ } prog_bind_map; - struct { /* struct used by BPF_TOKEN_CREATE command */ - __u32 flags; - __u32 bpffs_fd; - } token_create; - } __attribute__((aligned(8))); /* The description below is an attempt at providing documentation to eBPF diff --git a/kernel/bpf/Makefile b/kernel/bpf/Makefile index 4ce95acfcaa7..f526b7573e97 100644 --- a/kernel/bpf/Makefile +++ b/kernel/bpf/Makefile @@ -6,7 +6,7 @@ cflags-nogcse-$(CONFIG_X86)$(CONFIG_CC_IS_GCC) := -fno-gcse endif CFLAGS_core.o += $(call cc-disable-warning, override-init) $(cflags-nogcse-yy) -obj-$(CONFIG_BPF_SYSCALL) += syscall.o verifier.o inode.o helpers.o tnum.o log.o token.o +obj-$(CONFIG_BPF_SYSCALL) += syscall.o verifier.o inode.o helpers.o tnum.o log.o obj-$(CONFIG_BPF_SYSCALL) += bpf_iter.o map_iter.o task_iter.o prog_iter.o link_iter.o obj-$(CONFIG_BPF_SYSCALL) += hashtab.o arraymap.o percpu_freelist.o bpf_lru_list.o lpm_trie.o map_in_map.o bloom_filter.o obj-$(CONFIG_BPF_SYSCALL) += local_storage.o queue_stack_maps.o ringbuf.o diff --git a/kernel/bpf/arraymap.c b/kernel/bpf/arraymap.c index 13358675ff2e..0bdbbbeab155 100644 --- a/kernel/bpf/arraymap.c +++ b/kernel/bpf/arraymap.c @@ -82,7 +82,7 @@ static struct bpf_map *array_map_alloc(union bpf_attr *attr) bool percpu = attr->map_type == BPF_MAP_TYPE_PERCPU_ARRAY; int numa_node = bpf_map_attr_numa_node(attr); u32 elem_size, index_mask, max_entries; - bool bypass_spec_v1 = bpf_bypass_spec_v1(NULL); + bool bypass_spec_v1 = bpf_bypass_spec_v1(); u64 array_size, mask64; struct bpf_array *array; diff --git a/kernel/bpf/bpf_lsm.c b/kernel/bpf/bpf_lsm.c index 63b4dc495125..e8e910395bf6 100644 --- a/kernel/bpf/bpf_lsm.c +++ b/kernel/bpf/bpf_lsm.c @@ -260,15 +260,9 @@ bpf_lsm_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) BTF_SET_START(sleepable_lsm_hooks) BTF_ID(func, bpf_lsm_bpf) BTF_ID(func, bpf_lsm_bpf_map) -BTF_ID(func, bpf_lsm_bpf_map_create) -BTF_ID(func, bpf_lsm_bpf_map_free) +BTF_ID(func, bpf_lsm_bpf_map_alloc_security) +BTF_ID(func, bpf_lsm_bpf_map_free_security) BTF_ID(func, bpf_lsm_bpf_prog) -BTF_ID(func, bpf_lsm_bpf_prog_load) -BTF_ID(func, bpf_lsm_bpf_prog_free) -BTF_ID(func, bpf_lsm_bpf_token_create) -BTF_ID(func, bpf_lsm_bpf_token_free) -BTF_ID(func, bpf_lsm_bpf_token_cmd) -BTF_ID(func, bpf_lsm_bpf_token_capable) BTF_ID(func, bpf_lsm_bprm_check_security) BTF_ID(func, bpf_lsm_bprm_committed_creds) BTF_ID(func, bpf_lsm_bprm_committing_creds) @@ -363,8 +357,9 @@ BTF_ID(func, bpf_lsm_userns_create) BTF_SET_END(sleepable_lsm_hooks) BTF_SET_START(untrusted_lsm_hooks) -BTF_ID(func, bpf_lsm_bpf_map_free) -BTF_ID(func, bpf_lsm_bpf_prog_free) +BTF_ID(func, bpf_lsm_bpf_map_free_security) +BTF_ID(func, bpf_lsm_bpf_prog_alloc_security) +BTF_ID(func, bpf_lsm_bpf_prog_free_security) BTF_ID(func, bpf_lsm_file_alloc_security) BTF_ID(func, bpf_lsm_file_free_security) #ifdef CONFIG_SECURITY_NETWORK diff --git a/kernel/bpf/cgroup.c b/kernel/bpf/cgroup.c index 98e0e3835b28..491d20038cbe 100644 --- a/kernel/bpf/cgroup.c +++ b/kernel/bpf/cgroup.c @@ -1630,7 +1630,7 @@ cgroup_dev_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) case BPF_FUNC_perf_event_output: return &bpf_event_output_data_proto; default: - return bpf_base_func_proto(func_id, prog); + return bpf_base_func_proto(func_id); } } @@ -2191,7 +2191,7 @@ sysctl_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) case BPF_FUNC_perf_event_output: return &bpf_event_output_data_proto; default: - return bpf_base_func_proto(func_id, prog); + return bpf_base_func_proto(func_id); } } @@ -2348,7 +2348,7 @@ cg_sockopt_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) case BPF_FUNC_perf_event_output: return &bpf_event_output_data_proto; default: - return bpf_base_func_proto(func_id, prog); + return bpf_base_func_proto(func_id); } } diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c index 14ace23d517b..ea6843be2616 100644 --- a/kernel/bpf/core.c +++ b/kernel/bpf/core.c @@ -682,7 +682,7 @@ static bool bpf_prog_kallsyms_candidate(const struct bpf_prog *fp) void bpf_prog_kallsyms_add(struct bpf_prog *fp) { if (!bpf_prog_kallsyms_candidate(fp) || - !bpf_token_capable(fp->aux->token, CAP_BPF)) + !bpf_capable()) return; bpf_prog_ksym_set_addr(fp); @@ -2779,7 +2779,6 @@ void bpf_prog_free(struct bpf_prog *fp) if (aux->dst_prog) bpf_prog_put(aux->dst_prog); - bpf_token_put(aux->token); INIT_WORK(&aux->work, bpf_prog_free_deferred); schedule_work(&aux->work); } diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c index 07fd4b5704f3..be72824f32b2 100644 --- a/kernel/bpf/helpers.c +++ b/kernel/bpf/helpers.c @@ -1679,7 +1679,7 @@ const struct bpf_func_proto bpf_probe_read_kernel_str_proto __weak; const struct bpf_func_proto bpf_task_pt_regs_proto __weak; const struct bpf_func_proto * -bpf_base_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) +bpf_base_func_proto(enum bpf_func_id func_id) { switch (func_id) { case BPF_FUNC_map_lookup_elem: @@ -1730,7 +1730,7 @@ bpf_base_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) break; } - if (!bpf_token_capable(prog->aux->token, CAP_BPF)) + if (!bpf_capable()) return NULL; switch (func_id) { @@ -1788,7 +1788,7 @@ bpf_base_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) break; } - if (!bpf_token_capable(prog->aux->token, CAP_PERFMON)) + if (!perfmon_capable()) return NULL; switch (func_id) { diff --git a/kernel/bpf/inode.c b/kernel/bpf/inode.c index 4383b3d13a55..1aafb2ff2e95 100644 --- a/kernel/bpf/inode.c +++ b/kernel/bpf/inode.c @@ -20,7 +20,6 @@ #include #include #include -#include #include "preload/bpf_preload.h" enum bpf_type { @@ -99,9 +98,9 @@ static const struct inode_operations bpf_prog_iops = { }; static const struct inode_operations bpf_map_iops = { }; static const struct inode_operations bpf_link_iops = { }; -struct inode *bpf_get_inode(struct super_block *sb, - const struct inode *dir, - umode_t mode) +static struct inode *bpf_get_inode(struct super_block *sb, + const struct inode *dir, + umode_t mode) { struct inode *inode; @@ -595,183 +594,15 @@ struct bpf_prog *bpf_prog_get_type_path(const char *name, enum bpf_prog_type typ } EXPORT_SYMBOL(bpf_prog_get_type_path); -struct bpffs_btf_enums { - const struct btf *btf; - const struct btf_type *cmd_t; - const struct btf_type *map_t; - const struct btf_type *prog_t; - const struct btf_type *attach_t; -}; - -static int find_bpffs_btf_enums(struct bpffs_btf_enums *info) -{ - const struct btf *btf; - const struct btf_type *t; - const char *name; - int i, n; - - memset(info, 0, sizeof(*info)); - - btf = bpf_get_btf_vmlinux(); - if (IS_ERR(btf)) - return PTR_ERR(btf); - if (!btf) - return -ENOENT; - - info->btf = btf; - - for (i = 1, n = btf_nr_types(btf); i < n; i++) { - t = btf_type_by_id(btf, i); - if (!btf_type_is_enum(t)) - continue; - - name = btf_name_by_offset(btf, t->name_off); - if (!name) - continue; - - if (strcmp(name, "bpf_cmd") == 0) - info->cmd_t = t; - else if (strcmp(name, "bpf_map_type") == 0) - info->map_t = t; - else if (strcmp(name, "bpf_prog_type") == 0) - info->prog_t = t; - else if (strcmp(name, "bpf_attach_type") == 0) - info->attach_t = t; - else - continue; - - if (info->cmd_t && info->map_t && info->prog_t && info->attach_t) - return 0; - } - - return -ESRCH; -} - -static bool find_btf_enum_const(const struct btf *btf, const struct btf_type *enum_t, - const char *prefix, const char *str, int *value) -{ - const struct btf_enum *e; - const char *name; - int i, n, pfx_len = strlen(prefix); - - *value = 0; - - if (!btf || !enum_t) - return false; - - for (i = 0, n = btf_vlen(enum_t); i < n; i++) { - e = &btf_enum(enum_t)[i]; - - name = btf_name_by_offset(btf, e->name_off); - if (!name || strncasecmp(name, prefix, pfx_len) != 0) - continue; - - /* match symbolic name case insensitive and ignoring prefix */ - if (strcasecmp(name + pfx_len, str) == 0) { - *value = e->val; - return true; - } - } - - return false; -} - -static void seq_print_delegate_opts(struct seq_file *m, - const char *opt_name, - const struct btf *btf, - const struct btf_type *enum_t, - const char *prefix, - u64 delegate_msk, u64 any_msk) -{ - const struct btf_enum *e; - bool first = true; - const char *name; - u64 msk; - int i, n, pfx_len = strlen(prefix); - - delegate_msk &= any_msk; /* clear unknown bits */ - - if (delegate_msk == 0) - return; - - seq_printf(m, ",%s", opt_name); - if (delegate_msk == any_msk) { - seq_printf(m, "=any"); - return; - } - - if (btf && enum_t) { - for (i = 0, n = btf_vlen(enum_t); i < n; i++) { - e = &btf_enum(enum_t)[i]; - name = btf_name_by_offset(btf, e->name_off); - if (!name || strncasecmp(name, prefix, pfx_len) != 0) - continue; - msk = 1ULL << e->val; - if (delegate_msk & msk) { - /* emit lower-case name without prefix */ - seq_printf(m, "%c", first ? '=' : ':'); - name += pfx_len; - while (*name) { - seq_printf(m, "%c", tolower(*name)); - name++; - } - - delegate_msk &= ~msk; - first = false; - } - } - } - if (delegate_msk) - seq_printf(m, "%c0x%llx", first ? '=' : ':', delegate_msk); -} - /* * Display the mount options in /proc/mounts. */ static int bpf_show_options(struct seq_file *m, struct dentry *root) { - struct bpf_mount_opts *opts = root->d_sb->s_fs_info; - struct inode *inode = d_inode(root); - umode_t mode = inode->i_mode & S_IALLUGO & ~S_ISVTX; - u64 mask; - - if (!uid_eq(inode->i_uid, GLOBAL_ROOT_UID)) - seq_printf(m, ",uid=%u", - from_kuid_munged(&init_user_ns, inode->i_uid)); - if (!gid_eq(inode->i_gid, GLOBAL_ROOT_GID)) - seq_printf(m, ",gid=%u", - from_kgid_munged(&init_user_ns, inode->i_gid)); + umode_t mode = d_inode(root)->i_mode & S_IALLUGO & ~S_ISVTX; + if (mode != S_IRWXUGO) seq_printf(m, ",mode=%o", mode); - - if (opts->delegate_cmds || opts->delegate_maps || - opts->delegate_progs || opts->delegate_attachs) { - struct bpffs_btf_enums info; - - /* ignore errors, fallback to hex */ - (void)find_bpffs_btf_enums(&info); - - mask = (1ULL << __MAX_BPF_CMD) - 1; - seq_print_delegate_opts(m, "delegate_cmds", - info.btf, info.cmd_t, "BPF_", - opts->delegate_cmds, mask); - - mask = (1ULL << __MAX_BPF_MAP_TYPE) - 1; - seq_print_delegate_opts(m, "delegate_maps", - info.btf, info.map_t, "BPF_MAP_TYPE_", - opts->delegate_maps, mask); - - mask = (1ULL << __MAX_BPF_PROG_TYPE) - 1; - seq_print_delegate_opts(m, "delegate_progs", - info.btf, info.prog_t, "BPF_PROG_TYPE_", - opts->delegate_progs, mask); - - mask = (1ULL << __MAX_BPF_ATTACH_TYPE) - 1; - seq_print_delegate_opts(m, "delegate_attachs", - info.btf, info.attach_t, "BPF_", - opts->delegate_attachs, mask); - } - return 0; } @@ -786,7 +617,7 @@ static void bpf_free_inode(struct inode *inode) free_inode_nonrcu(inode); } -const struct super_operations bpf_super_ops = { +static const struct super_operations bpf_super_ops = { .statfs = simple_statfs, .drop_inode = generic_delete_inode, .show_options = bpf_show_options, @@ -794,33 +625,23 @@ const struct super_operations bpf_super_ops = { }; enum { - OPT_UID, - OPT_GID, OPT_MODE, - OPT_DELEGATE_CMDS, - OPT_DELEGATE_MAPS, - OPT_DELEGATE_PROGS, - OPT_DELEGATE_ATTACHS, }; static const struct fs_parameter_spec bpf_fs_parameters[] = { - fsparam_u32 ("uid", OPT_UID), - fsparam_u32 ("gid", OPT_GID), fsparam_u32oct ("mode", OPT_MODE), - fsparam_string ("delegate_cmds", OPT_DELEGATE_CMDS), - fsparam_string ("delegate_maps", OPT_DELEGATE_MAPS), - fsparam_string ("delegate_progs", OPT_DELEGATE_PROGS), - fsparam_string ("delegate_attachs", OPT_DELEGATE_ATTACHS), {} }; +struct bpf_mount_opts { + umode_t mode; +}; + static int bpf_parse_param(struct fs_context *fc, struct fs_parameter *param) { - struct bpf_mount_opts *opts = fc->s_fs_info; + struct bpf_mount_opts *opts = fc->fs_private; struct fs_parse_result result; - kuid_t uid; - kgid_t gid; - int opt, err; + int opt; opt = fs_parse(fc, bpf_fs_parameters, param, &result); if (opt < 0) { @@ -841,104 +662,12 @@ static int bpf_parse_param(struct fs_context *fc, struct fs_parameter *param) } switch (opt) { - case OPT_UID: - uid = make_kuid(current_user_ns(), result.uint_32); - if (!uid_valid(uid)) - goto bad_value; - - /* - * The requested uid must be representable in the - * filesystem's idmapping. - */ - if (!kuid_has_mapping(fc->user_ns, uid)) - goto bad_value; - - opts->uid = uid; - break; - case OPT_GID: - gid = make_kgid(current_user_ns(), result.uint_32); - if (!gid_valid(gid)) - goto bad_value; - - /* - * The requested gid must be representable in the - * filesystem's idmapping. - */ - if (!kgid_has_mapping(fc->user_ns, gid)) - goto bad_value; - - opts->gid = gid; - break; case OPT_MODE: opts->mode = result.uint_32 & S_IALLUGO; break; - case OPT_DELEGATE_CMDS: - case OPT_DELEGATE_MAPS: - case OPT_DELEGATE_PROGS: - case OPT_DELEGATE_ATTACHS: { - struct bpffs_btf_enums info; - const struct btf_type *enum_t; - const char *enum_pfx; - u64 *delegate_msk, msk = 0; - char *p; - int val; - - /* ignore errors, fallback to hex */ - (void)find_bpffs_btf_enums(&info); - - switch (opt) { - case OPT_DELEGATE_CMDS: - delegate_msk = &opts->delegate_cmds; - enum_t = info.cmd_t; - enum_pfx = "BPF_"; - break; - case OPT_DELEGATE_MAPS: - delegate_msk = &opts->delegate_maps; - enum_t = info.map_t; - enum_pfx = "BPF_MAP_TYPE_"; - break; - case OPT_DELEGATE_PROGS: - delegate_msk = &opts->delegate_progs; - enum_t = info.prog_t; - enum_pfx = "BPF_PROG_TYPE_"; - break; - case OPT_DELEGATE_ATTACHS: - delegate_msk = &opts->delegate_attachs; - enum_t = info.attach_t; - enum_pfx = "BPF_"; - break; - default: - return -EINVAL; - } - - while ((p = strsep(¶m->string, ":"))) { - if (strcmp(p, "any") == 0) { - msk |= ~0ULL; - } else if (find_btf_enum_const(info.btf, enum_t, enum_pfx, p, &val)) { - msk |= 1ULL << val; - } else { - err = kstrtou64(p, 0, &msk); - if (err) - return err; - } - } - - /* Setting delegation mount options requires privileges */ - if (msk && !capable(CAP_SYS_ADMIN)) - return -EPERM; - - *delegate_msk |= msk; - break; - } - default: - /* ignore unknown mount options */ - break; } return 0; - -bad_value: - return invalfc(fc, "Bad value for '%s'", param->key); } struct bpf_preload_ops *bpf_preload_ops; @@ -1010,14 +739,10 @@ out: static int bpf_fill_super(struct super_block *sb, struct fs_context *fc) { static const struct tree_descr bpf_rfiles[] = { { "" } }; - struct bpf_mount_opts *opts = sb->s_fs_info; + struct bpf_mount_opts *opts = fc->fs_private; struct inode *inode; int ret; - /* Mounting an instance of BPF FS requires privileges */ - if (fc->user_ns != &init_user_ns && !capable(CAP_SYS_ADMIN)) - return -EPERM; - ret = simple_fill_super(sb, BPF_FS_MAGIC, bpf_rfiles); if (ret) return ret; @@ -1025,8 +750,6 @@ static int bpf_fill_super(struct super_block *sb, struct fs_context *fc) sb->s_op = &bpf_super_ops; inode = sb->s_root->d_inode; - inode->i_uid = opts->uid; - inode->i_gid = opts->gid; inode->i_op = &bpf_dir_iops; inode->i_mode &= ~S_IALLUGO; populate_bpffs(sb->s_root); @@ -1041,7 +764,7 @@ static int bpf_get_tree(struct fs_context *fc) static void bpf_free_fc(struct fs_context *fc) { - kfree(fc->s_fs_info); + kfree(fc->fs_private); } static const struct fs_context_operations bpf_context_ops = { @@ -1062,35 +785,18 @@ static int bpf_init_fs_context(struct fs_context *fc) return -ENOMEM; opts->mode = S_IRWXUGO; - opts->uid = current_fsuid(); - opts->gid = current_fsgid(); - - /* start out with no BPF token delegation enabled */ - opts->delegate_cmds = 0; - opts->delegate_maps = 0; - opts->delegate_progs = 0; - opts->delegate_attachs = 0; - fc->s_fs_info = opts; + fc->fs_private = opts; fc->ops = &bpf_context_ops; return 0; } -static void bpf_kill_super(struct super_block *sb) -{ - struct bpf_mount_opts *opts = sb->s_fs_info; - - kill_litter_super(sb); - kfree(opts); -} - static struct file_system_type bpf_fs_type = { .owner = THIS_MODULE, .name = "bpf", .init_fs_context = bpf_init_fs_context, .parameters = bpf_fs_parameters, - .kill_sb = bpf_kill_super, - .fs_flags = FS_USERNS_MOUNT, + .kill_sb = kill_litter_super, }; static int __init bpf_init(void) diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 8faa1a20edf8..1bf9805ee185 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -1011,8 +1011,8 @@ int map_check_no_btf(const struct bpf_map *map, return -ENOTSUPP; } -static int map_check_btf(struct bpf_map *map, struct bpf_token *token, - const struct btf *btf, u32 btf_key_id, u32 btf_value_id) +static int map_check_btf(struct bpf_map *map, const struct btf *btf, + u32 btf_key_id, u32 btf_value_id) { const struct btf_type *key_type, *value_type; u32 key_size, value_size; @@ -1040,7 +1040,7 @@ static int map_check_btf(struct bpf_map *map, struct bpf_token *token, if (!IS_ERR_OR_NULL(map->record)) { int i; - if (!bpf_token_capable(token, CAP_BPF)) { + if (!bpf_capable()) { ret = -EPERM; goto free_map_tab; } @@ -1123,17 +1123,11 @@ free_map_tab: return ret; } -static bool bpf_net_capable(void) -{ - return capable(CAP_NET_ADMIN) || capable(CAP_SYS_ADMIN); -} - -#define BPF_MAP_CREATE_LAST_FIELD map_token_fd +#define BPF_MAP_CREATE_LAST_FIELD map_extra /* called via syscall */ static int map_create(union bpf_attr *attr) { const struct bpf_map_ops *ops; - struct bpf_token *token = NULL; int numa_node = bpf_map_attr_numa_node(attr); u32 map_type = attr->map_type; struct bpf_map *map; @@ -1184,32 +1178,14 @@ static int map_create(union bpf_attr *attr) if (!ops->map_mem_usage) return -EINVAL; - if (attr->map_token_fd) { - token = bpf_token_get_from_fd(attr->map_token_fd); - if (IS_ERR(token)) - return PTR_ERR(token); - - /* if current token doesn't grant map creation permissions, - * then we can't use this token, so ignore it and rely on - * system-wide capabilities checks - */ - if (!bpf_token_allow_cmd(token, BPF_MAP_CREATE) || - !bpf_token_allow_map_type(token, attr->map_type)) { - bpf_token_put(token); - token = NULL; - } - } - - err = -EPERM; - /* Intent here is for unprivileged_bpf_disabled to block BPF map * creation for unprivileged users; other actions depend * on fd availability and access to bpffs, so are dependent on * object creation success. Even with unprivileged BPF disabled, * capability checks are still carried out. */ - if (sysctl_unprivileged_bpf_disabled && !bpf_token_capable(token, CAP_BPF)) - goto put_token; + if (sysctl_unprivileged_bpf_disabled && !bpf_capable()) + return -EPERM; /* check privileged map type permissions */ switch (map_type) { @@ -1242,27 +1218,25 @@ static int map_create(union bpf_attr *attr) case BPF_MAP_TYPE_LRU_PERCPU_HASH: case BPF_MAP_TYPE_STRUCT_OPS: case BPF_MAP_TYPE_CPUMAP: - if (!bpf_token_capable(token, CAP_BPF)) - goto put_token; + if (!bpf_capable()) + return -EPERM; break; case BPF_MAP_TYPE_SOCKMAP: case BPF_MAP_TYPE_SOCKHASH: case BPF_MAP_TYPE_DEVMAP: case BPF_MAP_TYPE_DEVMAP_HASH: case BPF_MAP_TYPE_XSKMAP: - if (!bpf_token_capable(token, CAP_NET_ADMIN)) - goto put_token; + if (!capable(CAP_NET_ADMIN)) + return -EPERM; break; default: WARN(1, "unsupported map type %d", map_type); - goto put_token; + return -EPERM; } map = ops->map_alloc(attr); - if (IS_ERR(map)) { - err = PTR_ERR(map); - goto put_token; - } + if (IS_ERR(map)) + return PTR_ERR(map); map->ops = ops; map->map_type = map_type; @@ -1299,7 +1273,7 @@ static int map_create(union bpf_attr *attr) map->btf = btf; if (attr->btf_value_type_id) { - err = map_check_btf(map, token, btf, attr->btf_key_type_id, + err = map_check_btf(map, btf, attr->btf_key_type_id, attr->btf_value_type_id); if (err) goto free_map; @@ -1311,16 +1285,15 @@ static int map_create(union bpf_attr *attr) attr->btf_vmlinux_value_type_id; } - err = security_bpf_map_create(map, attr, token); + err = security_bpf_map_alloc(map); if (err) - goto free_map_sec; + goto free_map; err = bpf_map_alloc_id(map); if (err) goto free_map_sec; bpf_map_save_memcg(map); - bpf_token_put(token); err = bpf_map_new_fd(map, f_flags); if (err < 0) { @@ -1341,8 +1314,6 @@ free_map_sec: free_map: btf_put(map->btf); map->ops->map_free(map); -put_token: - bpf_token_put(token); return err; } @@ -2173,7 +2144,7 @@ static void __bpf_prog_put_rcu(struct rcu_head *rcu) kvfree(aux->func_info); kfree(aux->func_info_aux); free_uid(aux->user); - security_bpf_prog_free(aux->prog); + security_bpf_prog_free(aux); bpf_prog_free(aux->prog); } @@ -2619,15 +2590,13 @@ static bool is_perfmon_prog_type(enum bpf_prog_type prog_type) } /* last field in 'union bpf_attr' used by this command */ -#define BPF_PROG_LOAD_LAST_FIELD prog_token_fd +#define BPF_PROG_LOAD_LAST_FIELD log_true_size static int bpf_prog_load(union bpf_attr *attr, bpfptr_t uattr, u32 uattr_size) { enum bpf_prog_type type = attr->prog_type; struct bpf_prog *prog, *dst_prog = NULL; struct btf *attach_btf = NULL; - struct bpf_token *token = NULL; - bool bpf_cap; int err; char license[128]; @@ -2644,31 +2613,10 @@ static int bpf_prog_load(union bpf_attr *attr, bpfptr_t uattr, u32 uattr_size) BPF_F_TEST_REG_INVARIANTS)) return -EINVAL; - bpf_prog_load_fixup_attach_type(attr); - - if (attr->prog_token_fd) { - token = bpf_token_get_from_fd(attr->prog_token_fd); - if (IS_ERR(token)) - return PTR_ERR(token); - /* if current token doesn't grant prog loading permissions, - * then we can't use this token, so ignore it and rely on - * system-wide capabilities checks - */ - if (!bpf_token_allow_cmd(token, BPF_PROG_LOAD) || - !bpf_token_allow_prog_type(token, attr->prog_type, - attr->expected_attach_type)) { - bpf_token_put(token); - token = NULL; - } - } - - bpf_cap = bpf_token_capable(token, CAP_BPF); - err = -EPERM; - if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && (attr->prog_flags & BPF_F_ANY_ALIGNMENT) && - !bpf_cap) - goto put_token; + !bpf_capable()) + return -EPERM; /* Intent here is for unprivileged_bpf_disabled to block BPF program * creation for unprivileged users; other actions depend @@ -2677,23 +2625,21 @@ static int bpf_prog_load(union bpf_attr *attr, bpfptr_t uattr, u32 uattr_size) * capability checks are still carried out for these * and other operations. */ - if (sysctl_unprivileged_bpf_disabled && !bpf_cap) - goto put_token; + if (sysctl_unprivileged_bpf_disabled && !bpf_capable()) + return -EPERM; if (attr->insn_cnt == 0 || - attr->insn_cnt > (bpf_cap ? BPF_COMPLEXITY_LIMIT_INSNS : BPF_MAXINSNS)) { - err = -E2BIG; - goto put_token; - } + attr->insn_cnt > (bpf_capable() ? BPF_COMPLEXITY_LIMIT_INSNS : BPF_MAXINSNS)) + return -E2BIG; if (type != BPF_PROG_TYPE_SOCKET_FILTER && type != BPF_PROG_TYPE_CGROUP_SKB && - !bpf_cap) - goto put_token; + !bpf_capable()) + return -EPERM; - if (is_net_admin_prog_type(type) && !bpf_token_capable(token, CAP_NET_ADMIN)) - goto put_token; - if (is_perfmon_prog_type(type) && !bpf_token_capable(token, CAP_PERFMON)) - goto put_token; + if (is_net_admin_prog_type(type) && !capable(CAP_NET_ADMIN) && !capable(CAP_SYS_ADMIN)) + return -EPERM; + if (is_perfmon_prog_type(type) && !perfmon_capable()) + return -EPERM; /* attach_prog_fd/attach_btf_obj_fd can specify fd of either bpf_prog * or btf, we need to check which one it is @@ -2703,33 +2649,27 @@ static int bpf_prog_load(union bpf_attr *attr, bpfptr_t uattr, u32 uattr_size) if (IS_ERR(dst_prog)) { dst_prog = NULL; attach_btf = btf_get_by_fd(attr->attach_btf_obj_fd); - if (IS_ERR(attach_btf)) { - err = -EINVAL; - goto put_token; - } + if (IS_ERR(attach_btf)) + return -EINVAL; if (!btf_is_kernel(attach_btf)) { /* attaching through specifying bpf_prog's BTF * objects directly might be supported eventually */ btf_put(attach_btf); - err = -ENOTSUPP; - goto put_token; + return -ENOTSUPP; } } } else if (attr->attach_btf_id) { /* fall back to vmlinux BTF, if BTF type ID is specified */ attach_btf = bpf_get_btf_vmlinux(); - if (IS_ERR(attach_btf)) { - err = PTR_ERR(attach_btf); - goto put_token; - } - if (!attach_btf) { - err = -EINVAL; - goto put_token; - } + if (IS_ERR(attach_btf)) + return PTR_ERR(attach_btf); + if (!attach_btf) + return -EINVAL; btf_get(attach_btf); } + bpf_prog_load_fixup_attach_type(attr); if (bpf_prog_load_check_attach(type, attr->expected_attach_type, attach_btf, attr->attach_btf_id, dst_prog)) { @@ -2737,8 +2677,7 @@ static int bpf_prog_load(union bpf_attr *attr, bpfptr_t uattr, u32 uattr_size) bpf_prog_put(dst_prog); if (attach_btf) btf_put(attach_btf); - err = -EINVAL; - goto put_token; + return -EINVAL; } /* plain bpf_prog allocation */ @@ -2748,8 +2687,7 @@ static int bpf_prog_load(union bpf_attr *attr, bpfptr_t uattr, u32 uattr_size) bpf_prog_put(dst_prog); if (attach_btf) btf_put(attach_btf); - err = -EINVAL; - goto put_token; + return -ENOMEM; } prog->expected_attach_type = attr->expected_attach_type; @@ -2760,9 +2698,9 @@ static int bpf_prog_load(union bpf_attr *attr, bpfptr_t uattr, u32 uattr_size) prog->aux->sleepable = attr->prog_flags & BPF_F_SLEEPABLE; prog->aux->xdp_has_frags = attr->prog_flags & BPF_F_XDP_HAS_FRAGS; - /* move token into prog->aux, reuse taken refcnt */ - prog->aux->token = token; - token = NULL; + err = security_bpf_prog_alloc(prog->aux); + if (err) + goto free_prog; prog->aux->user = get_current_user(); prog->len = attr->insn_cnt; @@ -2771,12 +2709,12 @@ static int bpf_prog_load(union bpf_attr *attr, bpfptr_t uattr, u32 uattr_size) if (copy_from_bpfptr(prog->insns, make_bpfptr(attr->insns, uattr.is_kernel), bpf_prog_insn_size(prog)) != 0) - goto free_prog; + goto free_prog_sec; /* copy eBPF program license from user space */ if (strncpy_from_bpfptr(license, make_bpfptr(attr->license, uattr.is_kernel), sizeof(license) - 1) < 0) - goto free_prog; + goto free_prog_sec; license[sizeof(license) - 1] = 0; /* eBPF programs must be GPL compatible to use GPL-ed functions */ @@ -2790,29 +2728,25 @@ static int bpf_prog_load(union bpf_attr *attr, bpfptr_t uattr, u32 uattr_size) if (bpf_prog_is_dev_bound(prog->aux)) { err = bpf_prog_dev_bound_init(prog, attr); if (err) - goto free_prog; + goto free_prog_sec; } if (type == BPF_PROG_TYPE_EXT && dst_prog && bpf_prog_is_dev_bound(dst_prog->aux)) { err = bpf_prog_dev_bound_inherit(prog, dst_prog); if (err) - goto free_prog; + goto free_prog_sec; } /* find program type: socket_filter vs tracing_filter */ err = find_prog_type(type, prog); if (err < 0) - goto free_prog; + goto free_prog_sec; prog->aux->load_time = ktime_get_boottime_ns(); err = bpf_obj_name_cpy(prog->aux->name, attr->prog_name, sizeof(attr->prog_name)); if (err < 0) - goto free_prog; - - err = security_bpf_prog_load(prog, attr, token); - if (err) goto free_prog_sec; /* run eBPF verifier */ @@ -2858,16 +2792,13 @@ free_used_maps: */ __bpf_prog_put_noref(prog, prog->aux->real_func_cnt); return err; - free_prog_sec: - security_bpf_prog_free(prog); -free_prog: free_uid(prog->aux->user); + security_bpf_prog_free(prog->aux); +free_prog: if (prog->aux->attach_btf) btf_put(prog->aux->attach_btf); bpf_prog_free(prog); -put_token: - bpf_token_put(token); return err; } @@ -3857,7 +3788,7 @@ static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog, case BPF_PROG_TYPE_SK_LOOKUP: return attach_type == prog->expected_attach_type ? 0 : -EINVAL; case BPF_PROG_TYPE_CGROUP_SKB: - if (!bpf_token_capable(prog->aux->token, CAP_NET_ADMIN)) + if (!capable(CAP_NET_ADMIN)) /* cg-skb progs can be loaded by unpriv user. * check permissions at attach time. */ @@ -4060,7 +3991,7 @@ static int bpf_prog_detach(const union bpf_attr *attr) static int bpf_prog_query(const union bpf_attr *attr, union bpf_attr __user *uattr) { - if (!bpf_net_capable()) + if (!capable(CAP_NET_ADMIN)) return -EPERM; if (CHECK_ATTR(BPF_PROG_QUERY)) return -EINVAL; @@ -4828,31 +4759,15 @@ static int bpf_obj_get_info_by_fd(const union bpf_attr *attr, return err; } -#define BPF_BTF_LOAD_LAST_FIELD btf_token_fd +#define BPF_BTF_LOAD_LAST_FIELD btf_log_true_size static int bpf_btf_load(const union bpf_attr *attr, bpfptr_t uattr, __u32 uattr_size) { - struct bpf_token *token = NULL; - if (CHECK_ATTR(BPF_BTF_LOAD)) return -EINVAL; - if (attr->btf_token_fd) { - token = bpf_token_get_from_fd(attr->btf_token_fd); - if (IS_ERR(token)) - return PTR_ERR(token); - if (!bpf_token_allow_cmd(token, BPF_BTF_LOAD)) { - bpf_token_put(token); - token = NULL; - } - } - - if (!bpf_token_capable(token, CAP_BPF)) { - bpf_token_put(token); + if (!bpf_capable()) return -EPERM; - } - - bpf_token_put(token); return btf_new_fd(attr, uattr, uattr_size); } @@ -5470,20 +5385,6 @@ out_prog_put: return ret; } -#define BPF_TOKEN_CREATE_LAST_FIELD token_create.bpffs_fd - -static int token_create(union bpf_attr *attr) -{ - if (CHECK_ATTR(BPF_TOKEN_CREATE)) - return -EINVAL; - - /* no flags are supported yet */ - if (attr->token_create.flags) - return -EINVAL; - - return bpf_token_create(attr); -} - static int __sys_bpf(int cmd, bpfptr_t uattr, unsigned int size) { union bpf_attr attr; @@ -5617,9 +5518,6 @@ static int __sys_bpf(int cmd, bpfptr_t uattr, unsigned int size) case BPF_PROG_BIND_MAP: err = bpf_prog_bind_map(&attr); break; - case BPF_TOKEN_CREATE: - err = token_create(&attr); - break; default: err = -EINVAL; break; @@ -5726,7 +5624,7 @@ static const struct bpf_func_proto bpf_sys_bpf_proto = { const struct bpf_func_proto * __weak tracing_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) { - return bpf_base_func_proto(func_id, prog); + return bpf_base_func_proto(func_id); } BPF_CALL_1(bpf_sys_close, u32, fd) @@ -5776,8 +5674,7 @@ syscall_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) { switch (func_id) { case BPF_FUNC_sys_bpf: - return !bpf_token_capable(prog->aux->token, CAP_PERFMON) - ? NULL : &bpf_sys_bpf_proto; + return !perfmon_capable() ? NULL : &bpf_sys_bpf_proto; case BPF_FUNC_btf_find_by_name_kind: return &bpf_btf_find_by_name_kind_proto; case BPF_FUNC_sys_close: diff --git a/kernel/bpf/token.c b/kernel/bpf/token.c deleted file mode 100644 index a86fccd57e2d..000000000000 --- a/kernel/bpf/token.c +++ /dev/null @@ -1,271 +0,0 @@ -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include - -bool bpf_token_capable(const struct bpf_token *token, int cap) -{ - /* BPF token allows ns_capable() level of capabilities, but only if - * token's userns is *exactly* the same as current user's userns - */ - if (token && current_user_ns() == token->userns) { - if (ns_capable(token->userns, cap) || - (cap != CAP_SYS_ADMIN && ns_capable(token->userns, CAP_SYS_ADMIN))) - return security_bpf_token_capable(token, cap) == 0; - } - /* otherwise fallback to capable() checks */ - return capable(cap) || (cap != CAP_SYS_ADMIN && capable(CAP_SYS_ADMIN)); -} - -void bpf_token_inc(struct bpf_token *token) -{ - atomic64_inc(&token->refcnt); -} - -static void bpf_token_free(struct bpf_token *token) -{ - security_bpf_token_free(token); - put_user_ns(token->userns); - kvfree(token); -} - -static void bpf_token_put_deferred(struct work_struct *work) -{ - struct bpf_token *token = container_of(work, struct bpf_token, work); - - bpf_token_free(token); -} - -void bpf_token_put(struct bpf_token *token) -{ - if (!token) - return; - - if (!atomic64_dec_and_test(&token->refcnt)) - return; - - INIT_WORK(&token->work, bpf_token_put_deferred); - schedule_work(&token->work); -} - -static int bpf_token_release(struct inode *inode, struct file *filp) -{ - struct bpf_token *token = filp->private_data; - - bpf_token_put(token); - return 0; -} - -static void bpf_token_show_fdinfo(struct seq_file *m, struct file *filp) -{ - struct bpf_token *token = filp->private_data; - u64 mask; - - BUILD_BUG_ON(__MAX_BPF_CMD >= 64); - mask = (1ULL << __MAX_BPF_CMD) - 1; - if ((token->allowed_cmds & mask) == mask) - seq_printf(m, "allowed_cmds:\tany\n"); - else - seq_printf(m, "allowed_cmds:\t0x%llx\n", token->allowed_cmds); - - BUILD_BUG_ON(__MAX_BPF_MAP_TYPE >= 64); - mask = (1ULL << __MAX_BPF_MAP_TYPE) - 1; - if ((token->allowed_maps & mask) == mask) - seq_printf(m, "allowed_maps:\tany\n"); - else - seq_printf(m, "allowed_maps:\t0x%llx\n", token->allowed_maps); - - BUILD_BUG_ON(__MAX_BPF_PROG_TYPE >= 64); - mask = (1ULL << __MAX_BPF_PROG_TYPE) - 1; - if ((token->allowed_progs & mask) == mask) - seq_printf(m, "allowed_progs:\tany\n"); - else - seq_printf(m, "allowed_progs:\t0x%llx\n", token->allowed_progs); - - BUILD_BUG_ON(__MAX_BPF_ATTACH_TYPE >= 64); - mask = (1ULL << __MAX_BPF_ATTACH_TYPE) - 1; - if ((token->allowed_attachs & mask) == mask) - seq_printf(m, "allowed_attachs:\tany\n"); - else - seq_printf(m, "allowed_attachs:\t0x%llx\n", token->allowed_attachs); -} - -#define BPF_TOKEN_INODE_NAME "bpf-token" - -static const struct inode_operations bpf_token_iops = { }; - -static const struct file_operations bpf_token_fops = { - .release = bpf_token_release, - .show_fdinfo = bpf_token_show_fdinfo, -}; - -int bpf_token_create(union bpf_attr *attr) -{ - struct bpf_mount_opts *mnt_opts; - struct bpf_token *token = NULL; - struct user_namespace *userns; - struct inode *inode; - struct file *file; - struct path path; - struct fd f; - umode_t mode; - int err, fd; - - f = fdget(attr->token_create.bpffs_fd); - if (!f.file) - return -EBADF; - - path = f.file->f_path; - path_get(&path); - fdput(f); - - if (path.dentry != path.mnt->mnt_sb->s_root) { - err = -EINVAL; - goto out_path; - } - if (path.mnt->mnt_sb->s_op != &bpf_super_ops) { - err = -EINVAL; - goto out_path; - } - err = path_permission(&path, MAY_ACCESS); - if (err) - goto out_path; - - userns = path.dentry->d_sb->s_user_ns; - /* - * Enforce that creators of BPF tokens are in the same user - * namespace as the BPF FS instance. This makes reasoning about - * permissions a lot easier and we can always relax this later. - */ - if (current_user_ns() != userns) { - err = -EPERM; - goto out_path; - } - if (!ns_capable(userns, CAP_BPF)) { - err = -EPERM; - goto out_path; - } - - mnt_opts = path.dentry->d_sb->s_fs_info; - if (mnt_opts->delegate_cmds == 0 && - mnt_opts->delegate_maps == 0 && - mnt_opts->delegate_progs == 0 && - mnt_opts->delegate_attachs == 0) { - err = -ENOENT; /* no BPF token delegation is set up */ - goto out_path; - } - - mode = S_IFREG | ((S_IRUSR | S_IWUSR) & ~current_umask()); - inode = bpf_get_inode(path.mnt->mnt_sb, NULL, mode); - if (IS_ERR(inode)) { - err = PTR_ERR(inode); - goto out_path; - } - - inode->i_op = &bpf_token_iops; - inode->i_fop = &bpf_token_fops; - clear_nlink(inode); /* make sure it is unlinked */ - - file = alloc_file_pseudo(inode, path.mnt, BPF_TOKEN_INODE_NAME, O_RDWR, &bpf_token_fops); - if (IS_ERR(file)) { - iput(inode); - err = PTR_ERR(file); - goto out_path; - } - - token = kvzalloc(sizeof(*token), GFP_USER); - if (!token) { - err = -ENOMEM; - goto out_file; - } - - atomic64_set(&token->refcnt, 1); - - /* remember bpffs owning userns for future ns_capable() checks */ - token->userns = get_user_ns(userns); - - token->allowed_cmds = mnt_opts->delegate_cmds; - token->allowed_maps = mnt_opts->delegate_maps; - token->allowed_progs = mnt_opts->delegate_progs; - token->allowed_attachs = mnt_opts->delegate_attachs; - - err = security_bpf_token_create(token, attr, &path); - if (err) - goto out_token; - - fd = get_unused_fd_flags(O_CLOEXEC); - if (fd < 0) { - err = fd; - goto out_token; - } - - file->private_data = token; - fd_install(fd, file); - - path_put(&path); - return fd; - -out_token: - bpf_token_free(token); -out_file: - fput(file); -out_path: - path_put(&path); - return err; -} - -struct bpf_token *bpf_token_get_from_fd(u32 ufd) -{ - struct fd f = fdget(ufd); - struct bpf_token *token; - - if (!f.file) - return ERR_PTR(-EBADF); - if (f.file->f_op != &bpf_token_fops) { - fdput(f); - return ERR_PTR(-EINVAL); - } - - token = f.file->private_data; - bpf_token_inc(token); - fdput(f); - - return token; -} - -bool bpf_token_allow_cmd(const struct bpf_token *token, enum bpf_cmd cmd) -{ - /* BPF token can be used only within exactly the same userns in which - * it was created - */ - if (!token || current_user_ns() != token->userns) - return false; - if (!(token->allowed_cmds & (1ULL << cmd))) - return false; - return security_bpf_token_cmd(token, cmd) == 0; -} - -bool bpf_token_allow_map_type(const struct bpf_token *token, enum bpf_map_type type) -{ - if (!token || type >= __MAX_BPF_MAP_TYPE) - return false; - - return token->allowed_maps & (1ULL << type); -} - -bool bpf_token_allow_prog_type(const struct bpf_token *token, - enum bpf_prog_type prog_type, - enum bpf_attach_type attach_type) -{ - if (!token || prog_type >= __MAX_BPF_PROG_TYPE || attach_type >= __MAX_BPF_ATTACH_TYPE) - return false; - - return (token->allowed_progs & (1ULL << prog_type)) && - (token->allowed_attachs & (1ULL << attach_type)); -} diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 9456ee0ad129..4ceec8c2a484 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -20594,12 +20594,7 @@ int bpf_check(struct bpf_prog **prog, union bpf_attr *attr, bpfptr_t uattr, __u3 env->prog = *prog; env->ops = bpf_verifier_ops[env->prog->type]; env->fd_array = make_bpfptr(attr->fd_array, uattr.is_kernel); - - env->allow_ptr_leaks = bpf_allow_ptr_leaks(env->prog->aux->token); - env->allow_uninit_stack = bpf_allow_uninit_stack(env->prog->aux->token); - env->bypass_spec_v1 = bpf_bypass_spec_v1(env->prog->aux->token); - env->bypass_spec_v4 = bpf_bypass_spec_v4(env->prog->aux->token); - env->bpf_capable = is_priv = bpf_token_capable(env->prog->aux->token, CAP_BPF); + is_priv = bpf_capable(); bpf_get_btf_vmlinux(); @@ -20631,6 +20626,12 @@ int bpf_check(struct bpf_prog **prog, union bpf_attr *attr, bpfptr_t uattr, __u3 if (attr->prog_flags & BPF_F_ANY_ALIGNMENT) env->strict_alignment = false; + env->allow_ptr_leaks = bpf_allow_ptr_leaks(); + env->allow_uninit_stack = bpf_allow_uninit_stack(); + env->bypass_spec_v1 = bpf_bypass_spec_v1(); + env->bypass_spec_v4 = bpf_bypass_spec_v4(); + env->bpf_capable = bpf_capable(); + if (is_priv) env->test_state_freq = attr->prog_flags & BPF_F_TEST_STATE_FREQ; env->test_reg_invariants = attr->prog_flags & BPF_F_TEST_REG_INVARIANTS; diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index 492d60e9c480..7ac6c52b25eb 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -1629,7 +1629,7 @@ bpf_tracing_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) case BPF_FUNC_trace_vprintk: return bpf_get_trace_vprintk_proto(); default: - return bpf_base_func_proto(func_id, prog); + return bpf_base_func_proto(func_id); } } diff --git a/net/core/filter.c b/net/core/filter.c index 3cc52b82bab8..24061f29c9dd 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -87,7 +87,7 @@ #include "dev.h" static const struct bpf_func_proto * -bpf_sk_base_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog); +bpf_sk_base_func_proto(enum bpf_func_id func_id); int copy_bpf_fprog_from_user(struct sock_fprog *dst, sockptr_t src, int len) { @@ -7862,7 +7862,7 @@ sock_filter_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) case BPF_FUNC_ktime_get_coarse_ns: return &bpf_ktime_get_coarse_ns_proto; default: - return bpf_base_func_proto(func_id, prog); + return bpf_base_func_proto(func_id); } } @@ -7955,7 +7955,7 @@ sock_addr_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) return NULL; } default: - return bpf_sk_base_func_proto(func_id, prog); + return bpf_sk_base_func_proto(func_id); } } @@ -7974,7 +7974,7 @@ sk_filter_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) case BPF_FUNC_perf_event_output: return &bpf_skb_event_output_proto; default: - return bpf_sk_base_func_proto(func_id, prog); + return bpf_sk_base_func_proto(func_id); } } @@ -8161,7 +8161,7 @@ tc_cls_act_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) #endif #endif default: - return bpf_sk_base_func_proto(func_id, prog); + return bpf_sk_base_func_proto(func_id); } } @@ -8220,7 +8220,7 @@ xdp_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) #endif #endif default: - return bpf_sk_base_func_proto(func_id, prog); + return bpf_sk_base_func_proto(func_id); } #if IS_MODULE(CONFIG_NF_CONNTRACK) && IS_ENABLED(CONFIG_DEBUG_INFO_BTF_MODULES) @@ -8281,7 +8281,7 @@ sock_ops_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) return &bpf_tcp_sock_proto; #endif /* CONFIG_INET */ default: - return bpf_sk_base_func_proto(func_id, prog); + return bpf_sk_base_func_proto(func_id); } } @@ -8323,7 +8323,7 @@ sk_msg_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) return &bpf_get_cgroup_classid_curr_proto; #endif default: - return bpf_sk_base_func_proto(func_id, prog); + return bpf_sk_base_func_proto(func_id); } } @@ -8367,7 +8367,7 @@ sk_skb_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) return &bpf_skc_lookup_tcp_proto; #endif default: - return bpf_sk_base_func_proto(func_id, prog); + return bpf_sk_base_func_proto(func_id); } } @@ -8378,7 +8378,7 @@ flow_dissector_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) case BPF_FUNC_skb_load_bytes: return &bpf_flow_dissector_load_bytes_proto; default: - return bpf_sk_base_func_proto(func_id, prog); + return bpf_sk_base_func_proto(func_id); } } @@ -8405,7 +8405,7 @@ lwt_out_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) case BPF_FUNC_skb_under_cgroup: return &bpf_skb_under_cgroup_proto; default: - return bpf_sk_base_func_proto(func_id, prog); + return bpf_sk_base_func_proto(func_id); } } @@ -8580,7 +8580,7 @@ static bool cg_skb_is_valid_access(int off, int size, return false; case bpf_ctx_range(struct __sk_buff, data): case bpf_ctx_range(struct __sk_buff, data_end): - if (!bpf_token_capable(prog->aux->token, CAP_BPF)) + if (!bpf_capable()) return false; break; } @@ -8592,7 +8592,7 @@ static bool cg_skb_is_valid_access(int off, int size, case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]): break; case bpf_ctx_range(struct __sk_buff, tstamp): - if (!bpf_token_capable(prog->aux->token, CAP_BPF)) + if (!bpf_capable()) return false; break; default: @@ -11236,7 +11236,7 @@ sk_reuseport_func_proto(enum bpf_func_id func_id, case BPF_FUNC_ktime_get_coarse_ns: return &bpf_ktime_get_coarse_ns_proto; default: - return bpf_base_func_proto(func_id, prog); + return bpf_base_func_proto(func_id); } } @@ -11418,7 +11418,7 @@ sk_lookup_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) case BPF_FUNC_sk_release: return &bpf_sk_release_proto; default: - return bpf_sk_base_func_proto(func_id, prog); + return bpf_sk_base_func_proto(func_id); } } @@ -11752,7 +11752,7 @@ const struct bpf_func_proto bpf_sock_from_file_proto = { }; static const struct bpf_func_proto * -bpf_sk_base_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) +bpf_sk_base_func_proto(enum bpf_func_id func_id) { const struct bpf_func_proto *func; @@ -11781,10 +11781,10 @@ bpf_sk_base_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) case BPF_FUNC_ktime_get_coarse_ns: return &bpf_ktime_get_coarse_ns_proto; default: - return bpf_base_func_proto(func_id, prog); + return bpf_base_func_proto(func_id); } - if (!bpf_token_capable(prog->aux->token, CAP_PERFMON)) + if (!perfmon_capable()) return NULL; return func; diff --git a/net/ipv4/bpf_tcp_ca.c b/net/ipv4/bpf_tcp_ca.c index 634cfafa583d..ae8b15e6896f 100644 --- a/net/ipv4/bpf_tcp_ca.c +++ b/net/ipv4/bpf_tcp_ca.c @@ -191,7 +191,7 @@ bpf_tcp_ca_get_func_proto(enum bpf_func_id func_id, case BPF_FUNC_ktime_get_coarse_ns: return &bpf_ktime_get_coarse_ns_proto; default: - return bpf_base_func_proto(func_id, prog); + return bpf_base_func_proto(func_id); } } diff --git a/net/netfilter/nf_bpf_link.c b/net/netfilter/nf_bpf_link.c index 5257d5e7eb09..0e4beae421f8 100644 --- a/net/netfilter/nf_bpf_link.c +++ b/net/netfilter/nf_bpf_link.c @@ -314,7 +314,7 @@ static bool nf_is_valid_access(int off, int size, enum bpf_access_type type, static const struct bpf_func_proto * bpf_nf_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) { - return bpf_base_func_proto(func_id, prog); + return bpf_base_func_proto(func_id); } const struct bpf_verifier_ops netfilter_verifier_ops = { diff --git a/security/security.c b/security/security.c index 088a79c35c26..dcb3e7014f9b 100644 --- a/security/security.c +++ b/security/security.c @@ -5167,87 +5167,29 @@ int security_bpf_prog(struct bpf_prog *prog) } /** - * security_bpf_map_create() - Check if BPF map creation is allowed - * @map: BPF map object - * @attr: BPF syscall attributes used to create BPF map - * @token: BPF token used to grant user access - * - * Do a check when the kernel creates a new BPF map. This is also the - * point where LSM blob is allocated for LSMs that need them. - * - * Return: Returns 0 on success, error on failure. - */ -int security_bpf_map_create(struct bpf_map *map, union bpf_attr *attr, - struct bpf_token *token) -{ - return call_int_hook(bpf_map_create, 0, map, attr, token); -} - -/** - * security_bpf_prog_load() - Check if loading of BPF program is allowed - * @prog: BPF program object - * @attr: BPF syscall attributes used to create BPF program - * @token: BPF token used to grant user access to BPF subsystem - * - * Perform an access control check when the kernel loads a BPF program and - * allocates associated BPF program object. This hook is also responsible for - * allocating any required LSM state for the BPF program. - * - * Return: Returns 0 on success, error on failure. - */ -int security_bpf_prog_load(struct bpf_prog *prog, union bpf_attr *attr, - struct bpf_token *token) -{ - return call_int_hook(bpf_prog_load, 0, prog, attr, token); -} - -/** - * security_bpf_token_create() - Check if creating of BPF token is allowed - * @token: BPF token object - * @attr: BPF syscall attributes used to create BPF token - * @path: path pointing to BPF FS mount point from which BPF token is created - * - * Do a check when the kernel instantiates a new BPF token object from BPF FS - * instance. This is also the point where LSM blob can be allocated for LSMs. - * - * Return: Returns 0 on success, error on failure. - */ -int security_bpf_token_create(struct bpf_token *token, union bpf_attr *attr, - struct path *path) -{ - return call_int_hook(bpf_token_create, 0, token, attr, path); -} - -/** - * security_bpf_token_cmd() - Check if BPF token is allowed to delegate - * requested BPF syscall command - * @token: BPF token object - * @cmd: BPF syscall command requested to be delegated by BPF token + * security_bpf_map_alloc() - Allocate a bpf map LSM blob + * @map: bpf map * - * Do a check when the kernel decides whether provided BPF token should allow - * delegation of requested BPF syscall command. + * Initialize the security field inside bpf map. * * Return: Returns 0 on success, error on failure. */ -int security_bpf_token_cmd(const struct bpf_token *token, enum bpf_cmd cmd) +int security_bpf_map_alloc(struct bpf_map *map) { - return call_int_hook(bpf_token_cmd, 0, token, cmd); + return call_int_hook(bpf_map_alloc_security, 0, map); } /** - * security_bpf_token_capable() - Check if BPF token is allowed to delegate - * requested BPF-related capability - * @token: BPF token object - * @cap: capabilities requested to be delegated by BPF token + * security_bpf_prog_alloc() - Allocate a bpf program LSM blob + * @aux: bpf program aux info struct * - * Do a check when the kernel decides whether provided BPF token should allow - * delegation of requested BPF-related capabilities. + * Initialize the security field inside bpf program. * * Return: Returns 0 on success, error on failure. */ -int security_bpf_token_capable(const struct bpf_token *token, int cap) +int security_bpf_prog_alloc(struct bpf_prog_aux *aux) { - return call_int_hook(bpf_token_capable, 0, token, cap); + return call_int_hook(bpf_prog_alloc_security, 0, aux); } /** @@ -5258,29 +5200,18 @@ int security_bpf_token_capable(const struct bpf_token *token, int cap) */ void security_bpf_map_free(struct bpf_map *map) { - call_void_hook(bpf_map_free, map); -} - -/** - * security_bpf_prog_free() - Free a BPF program's LSM blob - * @prog: BPF program struct - * - * Clean up the security information stored inside BPF program. - */ -void security_bpf_prog_free(struct bpf_prog *prog) -{ - call_void_hook(bpf_prog_free, prog); + call_void_hook(bpf_map_free_security, map); } /** - * security_bpf_token_free() - Free a BPF token's LSM blob - * @token: BPF token struct + * security_bpf_prog_free() - Free a bpf program's LSM blob + * @aux: bpf program aux info struct * - * Clean up the security information stored inside BPF token. + * Clean up the security information stored inside bpf prog. */ -void security_bpf_token_free(struct bpf_token *token) +void security_bpf_prog_free(struct bpf_prog_aux *aux) { - call_void_hook(bpf_token_free, token); + call_void_hook(bpf_prog_free_security, aux); } #endif /* CONFIG_BPF_SYSCALL */ diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 1501e95366a1..feda711c6b7b 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -6783,8 +6783,7 @@ static int selinux_bpf_prog(struct bpf_prog *prog) BPF__PROG_RUN, NULL); } -static int selinux_bpf_map_create(struct bpf_map *map, union bpf_attr *attr, - struct bpf_token *token) +static int selinux_bpf_map_alloc(struct bpf_map *map) { struct bpf_security_struct *bpfsec; @@ -6806,8 +6805,7 @@ static void selinux_bpf_map_free(struct bpf_map *map) kfree(bpfsec); } -static int selinux_bpf_prog_load(struct bpf_prog *prog, union bpf_attr *attr, - struct bpf_token *token) +static int selinux_bpf_prog_alloc(struct bpf_prog_aux *aux) { struct bpf_security_struct *bpfsec; @@ -6816,39 +6814,16 @@ static int selinux_bpf_prog_load(struct bpf_prog *prog, union bpf_attr *attr, return -ENOMEM; bpfsec->sid = current_sid(); - prog->aux->security = bpfsec; + aux->security = bpfsec; return 0; } -static void selinux_bpf_prog_free(struct bpf_prog *prog) +static void selinux_bpf_prog_free(struct bpf_prog_aux *aux) { - struct bpf_security_struct *bpfsec = prog->aux->security; + struct bpf_security_struct *bpfsec = aux->security; - prog->aux->security = NULL; - kfree(bpfsec); -} - -static int selinux_bpf_token_create(struct bpf_token *token, union bpf_attr *attr, - struct path *path) -{ - struct bpf_security_struct *bpfsec; - - bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL); - if (!bpfsec) - return -ENOMEM; - - bpfsec->sid = current_sid(); - token->security = bpfsec; - - return 0; -} - -static void selinux_bpf_token_free(struct bpf_token *token) -{ - struct bpf_security_struct *bpfsec = token->security; - - token->security = NULL; + aux->security = NULL; kfree(bpfsec); } #endif @@ -7204,9 +7179,8 @@ static struct security_hook_list selinux_hooks[] __ro_after_init = { LSM_HOOK_INIT(bpf, selinux_bpf), LSM_HOOK_INIT(bpf_map, selinux_bpf_map), LSM_HOOK_INIT(bpf_prog, selinux_bpf_prog), - LSM_HOOK_INIT(bpf_map_free, selinux_bpf_map_free), - LSM_HOOK_INIT(bpf_prog_free, selinux_bpf_prog_free), - LSM_HOOK_INIT(bpf_token_free, selinux_bpf_token_free), + LSM_HOOK_INIT(bpf_map_free_security, selinux_bpf_map_free), + LSM_HOOK_INIT(bpf_prog_free_security, selinux_bpf_prog_free), #endif #ifdef CONFIG_PERF_EVENTS @@ -7263,9 +7237,8 @@ static struct security_hook_list selinux_hooks[] __ro_after_init = { LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init), #endif #ifdef CONFIG_BPF_SYSCALL - LSM_HOOK_INIT(bpf_map_create, selinux_bpf_map_create), - LSM_HOOK_INIT(bpf_prog_load, selinux_bpf_prog_load), - LSM_HOOK_INIT(bpf_token_create, selinux_bpf_token_create), + LSM_HOOK_INIT(bpf_map_alloc_security, selinux_bpf_map_alloc), + LSM_HOOK_INIT(bpf_prog_alloc_security, selinux_bpf_prog_alloc), #endif #ifdef CONFIG_PERF_EVENTS LSM_HOOK_INIT(perf_event_alloc, selinux_perf_event_alloc), diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index e0545201b55f..7f24d898efbb 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -847,36 +847,6 @@ union bpf_iter_link_info { * Returns zero on success. On error, -1 is returned and *errno* * is set appropriately. * - * BPF_TOKEN_CREATE - * Description - * Create BPF token with embedded information about what - * BPF-related functionality it allows: - * - a set of allowed bpf() syscall commands; - * - a set of allowed BPF map types to be created with - * BPF_MAP_CREATE command, if BPF_MAP_CREATE itself is allowed; - * - a set of allowed BPF program types and BPF program attach - * types to be loaded with BPF_PROG_LOAD command, if - * BPF_PROG_LOAD itself is allowed. - * - * BPF token is created (derived) from an instance of BPF FS, - * assuming it has necessary delegation mount options specified. - * This BPF token can be passed as an extra parameter to various - * bpf() syscall commands to grant BPF subsystem functionality to - * unprivileged processes. - * - * When created, BPF token is "associated" with the owning - * user namespace of BPF FS instance (super block) that it was - * derived from, and subsequent BPF operations performed with - * BPF token would be performing capabilities checks (i.e., - * CAP_BPF, CAP_PERFMON, CAP_NET_ADMIN, CAP_SYS_ADMIN) within - * that user namespace. Without BPF token, such capabilities - * have to be granted in init user namespace, making bpf() - * syscall incompatible with user namespace, for the most part. - * - * Return - * A new file descriptor (a nonnegative integer), or -1 if an - * error occurred (in which case, *errno* is set appropriately). - * * NOTES * eBPF objects (maps and programs) can be shared between processes. * @@ -931,8 +901,6 @@ enum bpf_cmd { BPF_ITER_CREATE, BPF_LINK_DETACH, BPF_PROG_BIND_MAP, - BPF_TOKEN_CREATE, - __MAX_BPF_CMD, }; enum bpf_map_type { @@ -983,7 +951,6 @@ enum bpf_map_type { BPF_MAP_TYPE_BLOOM_FILTER, BPF_MAP_TYPE_USER_RINGBUF, BPF_MAP_TYPE_CGRP_STORAGE, - __MAX_BPF_MAP_TYPE }; /* Note that tracing related programs such as @@ -1028,7 +995,6 @@ enum bpf_prog_type { BPF_PROG_TYPE_SK_LOOKUP, BPF_PROG_TYPE_SYSCALL, /* a program that can execute syscalls */ BPF_PROG_TYPE_NETFILTER, - __MAX_BPF_PROG_TYPE }; enum bpf_attach_type { @@ -1437,7 +1403,6 @@ union bpf_attr { * to using 5 hash functions). */ __u64 map_extra; - __u32 map_token_fd; }; struct { /* anonymous struct used by BPF_MAP_*_ELEM commands */ @@ -1507,7 +1472,6 @@ union bpf_attr { * truncated), or smaller (if log buffer wasn't filled completely). */ __u32 log_true_size; - __u32 prog_token_fd; }; struct { /* anonymous struct used by BPF_OBJ_* commands */ @@ -1620,7 +1584,6 @@ union bpf_attr { * truncated), or smaller (if log buffer wasn't filled completely). */ __u32 btf_log_true_size; - __u32 btf_token_fd; }; struct { @@ -1751,11 +1714,6 @@ union bpf_attr { __u32 flags; /* extra flags */ } prog_bind_map; - struct { /* struct used by BPF_TOKEN_CREATE command */ - __u32 flags; - __u32 bpffs_fd; - } token_create; - } __attribute__((aligned(8))); /* The description below is an attempt at providing documentation to eBPF diff --git a/tools/lib/bpf/Build b/tools/lib/bpf/Build index b6619199a706..2d0c282c8588 100644 --- a/tools/lib/bpf/Build +++ b/tools/lib/bpf/Build @@ -1,4 +1,4 @@ libbpf-y := libbpf.o bpf.o nlattr.o btf.o libbpf_errno.o str_error.o \ netlink.o bpf_prog_linfo.o libbpf_probes.o hashmap.o \ btf_dump.o ringbuf.o strset.o linker.o gen_loader.o relo_core.o \ - usdt.o zip.o elf.o features.o + usdt.o zip.o elf.o diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c index 0ad8e532b3cf..9dc9625651dc 100644 --- a/tools/lib/bpf/bpf.c +++ b/tools/lib/bpf/bpf.c @@ -103,7 +103,7 @@ int sys_bpf_prog_load(union bpf_attr *attr, unsigned int size, int attempts) * [0] https://lore.kernel.org/bpf/20201201215900.3569844-1-guro@fb.com/ * [1] d05512618056 ("bpf: Add bpf_ktime_get_coarse_ns helper") */ -int probe_memcg_account(int token_fd) +int probe_memcg_account(void) { const size_t attr_sz = offsetofend(union bpf_attr, attach_btf_obj_fd); struct bpf_insn insns[] = { @@ -120,7 +120,6 @@ int probe_memcg_account(int token_fd) attr.insns = ptr_to_u64(insns); attr.insn_cnt = insn_cnt; attr.license = ptr_to_u64("GPL"); - attr.prog_token_fd = token_fd; prog_fd = sys_bpf_fd(BPF_PROG_LOAD, &attr, attr_sz); if (prog_fd >= 0) { @@ -147,7 +146,7 @@ int bump_rlimit_memlock(void) struct rlimit rlim; /* if kernel supports memcg-based accounting, skip bumping RLIMIT_MEMLOCK */ - if (memlock_bumped || feat_supported(NULL, FEAT_MEMCG_ACCOUNT)) + if (memlock_bumped || kernel_supports(NULL, FEAT_MEMCG_ACCOUNT)) return 0; memlock_bumped = true; @@ -170,7 +169,7 @@ int bpf_map_create(enum bpf_map_type map_type, __u32 max_entries, const struct bpf_map_create_opts *opts) { - const size_t attr_sz = offsetofend(union bpf_attr, map_token_fd); + const size_t attr_sz = offsetofend(union bpf_attr, map_extra); union bpf_attr attr; int fd; @@ -182,7 +181,7 @@ int bpf_map_create(enum bpf_map_type map_type, return libbpf_err(-EINVAL); attr.map_type = map_type; - if (map_name && feat_supported(NULL, FEAT_PROG_NAME)) + if (map_name && kernel_supports(NULL, FEAT_PROG_NAME)) libbpf_strlcpy(attr.map_name, map_name, sizeof(attr.map_name)); attr.key_size = key_size; attr.value_size = value_size; @@ -199,8 +198,6 @@ int bpf_map_create(enum bpf_map_type map_type, attr.numa_node = OPTS_GET(opts, numa_node, 0); attr.map_ifindex = OPTS_GET(opts, map_ifindex, 0); - attr.map_token_fd = OPTS_GET(opts, token_fd, 0); - fd = sys_bpf_fd(BPF_MAP_CREATE, &attr, attr_sz); return libbpf_err_errno(fd); } @@ -235,7 +232,7 @@ int bpf_prog_load(enum bpf_prog_type prog_type, const struct bpf_insn *insns, size_t insn_cnt, struct bpf_prog_load_opts *opts) { - const size_t attr_sz = offsetofend(union bpf_attr, prog_token_fd); + const size_t attr_sz = offsetofend(union bpf_attr, log_true_size); void *finfo = NULL, *linfo = NULL; const char *func_info, *line_info; __u32 log_size, log_level, attach_prog_fd, attach_btf_obj_fd; @@ -264,9 +261,8 @@ int bpf_prog_load(enum bpf_prog_type prog_type, attr.prog_flags = OPTS_GET(opts, prog_flags, 0); attr.prog_ifindex = OPTS_GET(opts, prog_ifindex, 0); attr.kern_version = OPTS_GET(opts, kern_version, 0); - attr.prog_token_fd = OPTS_GET(opts, token_fd, 0); - if (prog_name && feat_supported(NULL, FEAT_PROG_NAME)) + if (prog_name && kernel_supports(NULL, FEAT_PROG_NAME)) libbpf_strlcpy(attr.prog_name, prog_name, sizeof(attr.prog_name)); attr.license = ptr_to_u64(license); @@ -1186,7 +1182,7 @@ int bpf_raw_tracepoint_open(const char *name, int prog_fd) int bpf_btf_load(const void *btf_data, size_t btf_size, struct bpf_btf_load_opts *opts) { - const size_t attr_sz = offsetofend(union bpf_attr, btf_token_fd); + const size_t attr_sz = offsetofend(union bpf_attr, btf_log_true_size); union bpf_attr attr; char *log_buf; size_t log_size; @@ -1211,8 +1207,6 @@ int bpf_btf_load(const void *btf_data, size_t btf_size, struct bpf_btf_load_opts attr.btf = ptr_to_u64(btf_data); attr.btf_size = btf_size; - attr.btf_token_fd = OPTS_GET(opts, token_fd, 0); - /* log_level == 0 and log_buf != NULL means "try loading without * log_buf, but retry with log_buf and log_level=1 on error", which is * consistent across low-level and high-level BTF and program loading @@ -1293,20 +1287,3 @@ int bpf_prog_bind_map(int prog_fd, int map_fd, ret = sys_bpf(BPF_PROG_BIND_MAP, &attr, attr_sz); return libbpf_err_errno(ret); } - -int bpf_token_create(int bpffs_fd, struct bpf_token_create_opts *opts) -{ - const size_t attr_sz = offsetofend(union bpf_attr, token_create); - union bpf_attr attr; - int fd; - - if (!OPTS_VALID(opts, bpf_token_create_opts)) - return libbpf_err(-EINVAL); - - memset(&attr, 0, attr_sz); - attr.token_create.bpffs_fd = bpffs_fd; - attr.token_create.flags = OPTS_GET(opts, flags, 0); - - fd = sys_bpf_fd(BPF_TOKEN_CREATE, &attr, attr_sz); - return libbpf_err_errno(fd); -} diff --git a/tools/lib/bpf/bpf.h b/tools/lib/bpf/bpf.h index 991b86bfe7e4..d0f53772bdc0 100644 --- a/tools/lib/bpf/bpf.h +++ b/tools/lib/bpf/bpf.h @@ -51,11 +51,8 @@ struct bpf_map_create_opts { __u32 numa_node; __u32 map_ifindex; - - __u32 token_fd; - size_t :0; }; -#define bpf_map_create_opts__last_field token_fd +#define bpf_map_create_opts__last_field map_ifindex LIBBPF_API int bpf_map_create(enum bpf_map_type map_type, const char *map_name, @@ -105,10 +102,9 @@ struct bpf_prog_load_opts { * If kernel doesn't support this feature, log_size is left unchanged. */ __u32 log_true_size; - __u32 token_fd; size_t :0; }; -#define bpf_prog_load_opts__last_field token_fd +#define bpf_prog_load_opts__last_field log_true_size LIBBPF_API int bpf_prog_load(enum bpf_prog_type prog_type, const char *prog_name, const char *license, @@ -134,10 +130,9 @@ struct bpf_btf_load_opts { * If kernel doesn't support this feature, log_size is left unchanged. */ __u32 log_true_size; - __u32 token_fd; size_t :0; }; -#define bpf_btf_load_opts__last_field token_fd +#define bpf_btf_load_opts__last_field log_true_size LIBBPF_API int bpf_btf_load(const void *btf_data, size_t btf_size, struct bpf_btf_load_opts *opts); @@ -645,30 +640,6 @@ struct bpf_test_run_opts { LIBBPF_API int bpf_prog_test_run_opts(int prog_fd, struct bpf_test_run_opts *opts); -struct bpf_token_create_opts { - size_t sz; /* size of this struct for forward/backward compatibility */ - __u32 flags; - size_t :0; -}; -#define bpf_token_create_opts__last_field flags - -/** - * @brief **bpf_token_create()** creates a new instance of BPF token derived - * from specified BPF FS mount point. - * - * BPF token created with this API can be passed to bpf() syscall for - * commands like BPF_PROG_LOAD, BPF_MAP_CREATE, etc. - * - * @param bpffs_fd FD for BPF FS instance from which to derive a BPF token - * instance. - * @param opts optional BPF token creation options, can be NULL - * - * @return BPF token FD > 0, on success; negative error code, otherwise (errno - * is also set to the error code) - */ -LIBBPF_API int bpf_token_create(int bpffs_fd, - struct bpf_token_create_opts *opts); - #ifdef __cplusplus } /* extern "C" */ #endif diff --git a/tools/lib/bpf/btf.c b/tools/lib/bpf/btf.c index 63033c334320..ee95fd379d4d 100644 --- a/tools/lib/bpf/btf.c +++ b/tools/lib/bpf/btf.c @@ -1317,9 +1317,7 @@ struct btf *btf__parse_split(const char *path, struct btf *base_btf) static void *btf_get_raw_data(const struct btf *btf, __u32 *size, bool swap_endian); -int btf_load_into_kernel(struct btf *btf, - char *log_buf, size_t log_sz, __u32 log_level, - int token_fd) +int btf_load_into_kernel(struct btf *btf, char *log_buf, size_t log_sz, __u32 log_level) { LIBBPF_OPTS(bpf_btf_load_opts, opts); __u32 buf_sz = 0, raw_size; @@ -1369,7 +1367,6 @@ retry_load: opts.log_level = log_level; } - opts.token_fd = token_fd; btf->fd = bpf_btf_load(raw_data, raw_size, &opts); if (btf->fd < 0) { /* time to turn on verbose mode and try again */ @@ -1397,7 +1394,7 @@ done: int btf__load_into_kernel(struct btf *btf) { - return btf_load_into_kernel(btf, NULL, 0, 0, 0); + return btf_load_into_kernel(btf, NULL, 0, 0); } int btf__fd(const struct btf *btf) diff --git a/tools/lib/bpf/elf.c b/tools/lib/bpf/elf.c index c92e02394159..b02faec748a5 100644 --- a/tools/lib/bpf/elf.c +++ b/tools/lib/bpf/elf.c @@ -11,6 +11,8 @@ #include "libbpf_internal.h" #include "str_error.h" +#define STRERR_BUFSIZE 128 + /* A SHT_GNU_versym section holds 16-bit words. This bit is set if * the symbol is hidden and can only be seen when referenced using an * explicit version number. This is a GNU extension. diff --git a/tools/lib/bpf/features.c b/tools/lib/bpf/features.c deleted file mode 100644 index ce98a334be21..000000000000 --- a/tools/lib/bpf/features.c +++ /dev/null @@ -1,478 +0,0 @@ -// SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) -/* Copyright (c) 2023 Meta Platforms, Inc. and affiliates. */ -#include -#include -#include "bpf.h" -#include "libbpf.h" -#include "libbpf_common.h" -#include "libbpf_internal.h" -#include "str_error.h" - -static inline __u64 ptr_to_u64(const void *ptr) -{ - return (__u64)(unsigned long)ptr; -} - -static int probe_fd(int fd) -{ - if (fd >= 0) - close(fd); - return fd >= 0; -} - -static int probe_kern_prog_name(int token_fd) -{ - const size_t attr_sz = offsetofend(union bpf_attr, prog_name); - struct bpf_insn insns[] = { - BPF_MOV64_IMM(BPF_REG_0, 0), - BPF_EXIT_INSN(), - }; - union bpf_attr attr; - int ret; - - memset(&attr, 0, attr_sz); - attr.prog_type = BPF_PROG_TYPE_SOCKET_FILTER; - attr.license = ptr_to_u64("GPL"); - attr.insns = ptr_to_u64(insns); - attr.insn_cnt = (__u32)ARRAY_SIZE(insns); - attr.prog_token_fd = token_fd; - libbpf_strlcpy(attr.prog_name, "libbpf_nametest", sizeof(attr.prog_name)); - - /* make sure loading with name works */ - ret = sys_bpf_prog_load(&attr, attr_sz, PROG_LOAD_ATTEMPTS); - return probe_fd(ret); -} - -static int probe_kern_global_data(int token_fd) -{ - char *cp, errmsg[STRERR_BUFSIZE]; - struct bpf_insn insns[] = { - BPF_LD_MAP_VALUE(BPF_REG_1, 0, 16), - BPF_ST_MEM(BPF_DW, BPF_REG_1, 0, 42), - BPF_MOV64_IMM(BPF_REG_0, 0), - BPF_EXIT_INSN(), - }; - LIBBPF_OPTS(bpf_map_create_opts, map_opts, .token_fd = token_fd); - LIBBPF_OPTS(bpf_prog_load_opts, prog_opts, .token_fd = token_fd); - int ret, map, insn_cnt = ARRAY_SIZE(insns); - - map = bpf_map_create(BPF_MAP_TYPE_ARRAY, "libbpf_global", sizeof(int), 32, 1, &map_opts); - if (map < 0) { - ret = -errno; - cp = libbpf_strerror_r(ret, errmsg, sizeof(errmsg)); - pr_warn("Error in %s():%s(%d). Couldn't create simple array map.\n", - __func__, cp, -ret); - return ret; - } - - insns[0].imm = map; - - ret = bpf_prog_load(BPF_PROG_TYPE_SOCKET_FILTER, NULL, "GPL", insns, insn_cnt, &prog_opts); - close(map); - return probe_fd(ret); -} - -static int probe_kern_btf(int token_fd) -{ - static const char strs[] = "\0int"; - __u32 types[] = { - /* int */ - BTF_TYPE_INT_ENC(1, BTF_INT_SIGNED, 0, 32, 4), - }; - - return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types), - strs, sizeof(strs), token_fd)); -} - -static int probe_kern_btf_func(int token_fd) -{ - static const char strs[] = "\0int\0x\0a"; - /* void x(int a) {} */ - __u32 types[] = { - /* int */ - BTF_TYPE_INT_ENC(1, BTF_INT_SIGNED, 0, 32, 4), /* [1] */ - /* FUNC_PROTO */ /* [2] */ - BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_FUNC_PROTO, 0, 1), 0), - BTF_PARAM_ENC(7, 1), - /* FUNC x */ /* [3] */ - BTF_TYPE_ENC(5, BTF_INFO_ENC(BTF_KIND_FUNC, 0, 0), 2), - }; - - return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types), - strs, sizeof(strs), token_fd)); -} - -static int probe_kern_btf_func_global(int token_fd) -{ - static const char strs[] = "\0int\0x\0a"; - /* static void x(int a) {} */ - __u32 types[] = { - /* int */ - BTF_TYPE_INT_ENC(1, BTF_INT_SIGNED, 0, 32, 4), /* [1] */ - /* FUNC_PROTO */ /* [2] */ - BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_FUNC_PROTO, 0, 1), 0), - BTF_PARAM_ENC(7, 1), - /* FUNC x BTF_FUNC_GLOBAL */ /* [3] */ - BTF_TYPE_ENC(5, BTF_INFO_ENC(BTF_KIND_FUNC, 0, BTF_FUNC_GLOBAL), 2), - }; - - return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types), - strs, sizeof(strs), token_fd)); -} - -static int probe_kern_btf_datasec(int token_fd) -{ - static const char strs[] = "\0x\0.data"; - /* static int a; */ - __u32 types[] = { - /* int */ - BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4), /* [1] */ - /* VAR x */ /* [2] */ - BTF_TYPE_ENC(1, BTF_INFO_ENC(BTF_KIND_VAR, 0, 0), 1), - BTF_VAR_STATIC, - /* DATASEC val */ /* [3] */ - BTF_TYPE_ENC(3, BTF_INFO_ENC(BTF_KIND_DATASEC, 0, 1), 4), - BTF_VAR_SECINFO_ENC(2, 0, 4), - }; - - return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types), - strs, sizeof(strs), token_fd)); -} - -static int probe_kern_btf_float(int token_fd) -{ - static const char strs[] = "\0float"; - __u32 types[] = { - /* float */ - BTF_TYPE_FLOAT_ENC(1, 4), - }; - - return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types), - strs, sizeof(strs), token_fd)); -} - -static int probe_kern_btf_decl_tag(int token_fd) -{ - static const char strs[] = "\0tag"; - __u32 types[] = { - /* int */ - BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4), /* [1] */ - /* VAR x */ /* [2] */ - BTF_TYPE_ENC(1, BTF_INFO_ENC(BTF_KIND_VAR, 0, 0), 1), - BTF_VAR_STATIC, - /* attr */ - BTF_TYPE_DECL_TAG_ENC(1, 2, -1), - }; - - return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types), - strs, sizeof(strs), token_fd)); -} - -static int probe_kern_btf_type_tag(int token_fd) -{ - static const char strs[] = "\0tag"; - __u32 types[] = { - /* int */ - BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4), /* [1] */ - /* attr */ - BTF_TYPE_TYPE_TAG_ENC(1, 1), /* [2] */ - /* ptr */ - BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_PTR, 0, 0), 2), /* [3] */ - }; - - return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types), - strs, sizeof(strs), token_fd)); -} - -static int probe_kern_array_mmap(int token_fd) -{ - LIBBPF_OPTS(bpf_map_create_opts, opts, - .map_flags = BPF_F_MMAPABLE, - .token_fd = token_fd, - ); - int fd; - - fd = bpf_map_create(BPF_MAP_TYPE_ARRAY, "libbpf_mmap", sizeof(int), sizeof(int), 1, &opts); - return probe_fd(fd); -} - -static int probe_kern_exp_attach_type(int token_fd) -{ - LIBBPF_OPTS(bpf_prog_load_opts, opts, - .expected_attach_type = BPF_CGROUP_INET_SOCK_CREATE, - .token_fd = token_fd, - ); - struct bpf_insn insns[] = { - BPF_MOV64_IMM(BPF_REG_0, 0), - BPF_EXIT_INSN(), - }; - int fd, insn_cnt = ARRAY_SIZE(insns); - - /* use any valid combination of program type and (optional) - * non-zero expected attach type (i.e., not a BPF_CGROUP_INET_INGRESS) - * to see if kernel supports expected_attach_type field for - * BPF_PROG_LOAD command - */ - fd = bpf_prog_load(BPF_PROG_TYPE_CGROUP_SOCK, NULL, "GPL", insns, insn_cnt, &opts); - return probe_fd(fd); -} - -static int probe_kern_probe_read_kernel(int token_fd) -{ - LIBBPF_OPTS(bpf_prog_load_opts, opts, .token_fd = token_fd); - struct bpf_insn insns[] = { - BPF_MOV64_REG(BPF_REG_1, BPF_REG_10), /* r1 = r10 (fp) */ - BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -8), /* r1 += -8 */ - BPF_MOV64_IMM(BPF_REG_2, 8), /* r2 = 8 */ - BPF_MOV64_IMM(BPF_REG_3, 0), /* r3 = 0 */ - BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_probe_read_kernel), - BPF_EXIT_INSN(), - }; - int fd, insn_cnt = ARRAY_SIZE(insns); - - fd = bpf_prog_load(BPF_PROG_TYPE_TRACEPOINT, NULL, "GPL", insns, insn_cnt, &opts); - return probe_fd(fd); -} - -static int probe_prog_bind_map(int token_fd) -{ - char *cp, errmsg[STRERR_BUFSIZE]; - struct bpf_insn insns[] = { - BPF_MOV64_IMM(BPF_REG_0, 0), - BPF_EXIT_INSN(), - }; - LIBBPF_OPTS(bpf_map_create_opts, map_opts, .token_fd = token_fd); - LIBBPF_OPTS(bpf_prog_load_opts, prog_opts, .token_fd = token_fd); - int ret, map, prog, insn_cnt = ARRAY_SIZE(insns); - - map = bpf_map_create(BPF_MAP_TYPE_ARRAY, "libbpf_det_bind", sizeof(int), 32, 1, &map_opts); - if (map < 0) { - ret = -errno; - cp = libbpf_strerror_r(ret, errmsg, sizeof(errmsg)); - pr_warn("Error in %s():%s(%d). Couldn't create simple array map.\n", - __func__, cp, -ret); - return ret; - } - - prog = bpf_prog_load(BPF_PROG_TYPE_SOCKET_FILTER, NULL, "GPL", insns, insn_cnt, &prog_opts); - if (prog < 0) { - close(map); - return 0; - } - - ret = bpf_prog_bind_map(prog, map, NULL); - - close(map); - close(prog); - - return ret >= 0; -} - -static int probe_module_btf(int token_fd) -{ - static const char strs[] = "\0int"; - __u32 types[] = { - /* int */ - BTF_TYPE_INT_ENC(1, BTF_INT_SIGNED, 0, 32, 4), - }; - struct bpf_btf_info info; - __u32 len = sizeof(info); - char name[16]; - int fd, err; - - fd = libbpf__load_raw_btf((char *)types, sizeof(types), strs, sizeof(strs), token_fd); - if (fd < 0) - return 0; /* BTF not supported at all */ - - memset(&info, 0, sizeof(info)); - info.name = ptr_to_u64(name); - info.name_len = sizeof(name); - - /* check that BPF_OBJ_GET_INFO_BY_FD supports specifying name pointer; - * kernel's module BTF support coincides with support for - * name/name_len fields in struct bpf_btf_info. - */ - err = bpf_btf_get_info_by_fd(fd, &info, &len); - close(fd); - return !err; -} - -static int probe_perf_link(int token_fd) -{ - struct bpf_insn insns[] = { - BPF_MOV64_IMM(BPF_REG_0, 0), - BPF_EXIT_INSN(), - }; - LIBBPF_OPTS(bpf_prog_load_opts, opts, .token_fd = token_fd); - int prog_fd, link_fd, err; - - prog_fd = bpf_prog_load(BPF_PROG_TYPE_TRACEPOINT, NULL, "GPL", - insns, ARRAY_SIZE(insns), &opts); - if (prog_fd < 0) - return -errno; - - /* use invalid perf_event FD to get EBADF, if link is supported; - * otherwise EINVAL should be returned - */ - link_fd = bpf_link_create(prog_fd, -1, BPF_PERF_EVENT, NULL); - err = -errno; /* close() can clobber errno */ - - if (link_fd >= 0) - close(link_fd); - close(prog_fd); - - return link_fd < 0 && err == -EBADF; -} - -static int probe_uprobe_multi_link(int token_fd) -{ - LIBBPF_OPTS(bpf_prog_load_opts, load_opts, - .expected_attach_type = BPF_TRACE_UPROBE_MULTI, - .token_fd = token_fd, - ); - LIBBPF_OPTS(bpf_link_create_opts, link_opts); - struct bpf_insn insns[] = { - BPF_MOV64_IMM(BPF_REG_0, 0), - BPF_EXIT_INSN(), - }; - int prog_fd, link_fd, err; - unsigned long offset = 0; - - prog_fd = bpf_prog_load(BPF_PROG_TYPE_KPROBE, NULL, "GPL", - insns, ARRAY_SIZE(insns), &load_opts); - if (prog_fd < 0) - return -errno; - - /* Creating uprobe in '/' binary should fail with -EBADF. */ - link_opts.uprobe_multi.path = "/"; - link_opts.uprobe_multi.offsets = &offset; - link_opts.uprobe_multi.cnt = 1; - - link_fd = bpf_link_create(prog_fd, -1, BPF_TRACE_UPROBE_MULTI, &link_opts); - err = -errno; /* close() can clobber errno */ - - if (link_fd >= 0) - close(link_fd); - close(prog_fd); - - return link_fd < 0 && err == -EBADF; -} - -static int probe_kern_bpf_cookie(int token_fd) -{ - struct bpf_insn insns[] = { - BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_get_attach_cookie), - BPF_EXIT_INSN(), - }; - LIBBPF_OPTS(bpf_prog_load_opts, opts, .token_fd = token_fd); - int ret, insn_cnt = ARRAY_SIZE(insns); - - ret = bpf_prog_load(BPF_PROG_TYPE_TRACEPOINT, NULL, "GPL", insns, insn_cnt, &opts); - return probe_fd(ret); -} - -static int probe_kern_btf_enum64(int token_fd) -{ - static const char strs[] = "\0enum64"; - __u32 types[] = { - BTF_TYPE_ENC(1, BTF_INFO_ENC(BTF_KIND_ENUM64, 0, 0), 8), - }; - - return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types), - strs, sizeof(strs), token_fd)); -} - -typedef int (*feature_probe_fn)(int /* token_fd */); - -static struct kern_feature_cache feature_cache; - -static struct kern_feature_desc { - const char *desc; - feature_probe_fn probe; -} feature_probes[__FEAT_CNT] = { - [FEAT_PROG_NAME] = { - "BPF program name", probe_kern_prog_name, - }, - [FEAT_GLOBAL_DATA] = { - "global variables", probe_kern_global_data, - }, - [FEAT_BTF] = { - "minimal BTF", probe_kern_btf, - }, - [FEAT_BTF_FUNC] = { - "BTF functions", probe_kern_btf_func, - }, - [FEAT_BTF_GLOBAL_FUNC] = { - "BTF global function", probe_kern_btf_func_global, - }, - [FEAT_BTF_DATASEC] = { - "BTF data section and variable", probe_kern_btf_datasec, - }, - [FEAT_ARRAY_MMAP] = { - "ARRAY map mmap()", probe_kern_array_mmap, - }, - [FEAT_EXP_ATTACH_TYPE] = { - "BPF_PROG_LOAD expected_attach_type attribute", - probe_kern_exp_attach_type, - }, - [FEAT_PROBE_READ_KERN] = { - "bpf_probe_read_kernel() helper", probe_kern_probe_read_kernel, - }, - [FEAT_PROG_BIND_MAP] = { - "BPF_PROG_BIND_MAP support", probe_prog_bind_map, - }, - [FEAT_MODULE_BTF] = { - "module BTF support", probe_module_btf, - }, - [FEAT_BTF_FLOAT] = { - "BTF_KIND_FLOAT support", probe_kern_btf_float, - }, - [FEAT_PERF_LINK] = { - "BPF perf link support", probe_perf_link, - }, - [FEAT_BTF_DECL_TAG] = { - "BTF_KIND_DECL_TAG support", probe_kern_btf_decl_tag, - }, - [FEAT_BTF_TYPE_TAG] = { - "BTF_KIND_TYPE_TAG support", probe_kern_btf_type_tag, - }, - [FEAT_MEMCG_ACCOUNT] = { - "memcg-based memory accounting", probe_memcg_account, - }, - [FEAT_BPF_COOKIE] = { - "BPF cookie support", probe_kern_bpf_cookie, - }, - [FEAT_BTF_ENUM64] = { - "BTF_KIND_ENUM64 support", probe_kern_btf_enum64, - }, - [FEAT_SYSCALL_WRAPPER] = { - "Kernel using syscall wrapper", probe_kern_syscall_wrapper, - }, - [FEAT_UPROBE_MULTI_LINK] = { - "BPF multi-uprobe link support", probe_uprobe_multi_link, - }, -}; - -bool feat_supported(struct kern_feature_cache *cache, enum kern_feature_id feat_id) -{ - struct kern_feature_desc *feat = &feature_probes[feat_id]; - int ret; - - /* assume global feature cache, unless custom one is provided */ - if (!cache) - cache = &feature_cache; - - if (READ_ONCE(cache->res[feat_id]) == FEAT_UNKNOWN) { - ret = feat->probe(cache->token_fd); - if (ret > 0) { - WRITE_ONCE(cache->res[feat_id], FEAT_SUPPORTED); - } else if (ret == 0) { - WRITE_ONCE(cache->res[feat_id], FEAT_MISSING); - } else { - pr_warn("Detection of kernel %s support failed: %d\n", feat->desc, ret); - WRITE_ONCE(cache->res[feat_id], FEAT_MISSING); - } - } - - return READ_ONCE(cache->res[feat_id]) == FEAT_SUPPORTED; -} diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 4b5ff9508e18..ac54ebc0629f 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -59,8 +59,6 @@ #define BPF_FS_MAGIC 0xcafe4a11 #endif -#define BPF_FS_DEFAULT_PATH "/sys/fs/bpf" - #define BPF_INSN_SZ (sizeof(struct bpf_insn)) /* vsprintf() in __base_pr() uses nonliteral format string. It may break @@ -695,10 +693,6 @@ struct bpf_object { struct usdt_manager *usdt_man; - struct kern_feature_cache *feat_cache; - char *token_path; - int token_fd; - char path[]; }; @@ -2198,7 +2192,7 @@ static int build_map_pin_path(struct bpf_map *map, const char *path) int err; if (!path) - path = BPF_FS_DEFAULT_PATH; + path = "/sys/fs/bpf"; err = pathname_concat(buf, sizeof(buf), path, bpf_map__name(map)); if (err) @@ -3285,7 +3279,7 @@ skip_exception_cb: } else { /* currently BPF_BTF_LOAD only supports log_level 1 */ err = btf_load_into_kernel(kern_btf, obj->log_buf, obj->log_size, - obj->log_level ? 1 : 0, obj->token_fd); + obj->log_level ? 1 : 0); } if (sanitize) { if (!err) { @@ -4608,63 +4602,6 @@ int bpf_map__set_max_entries(struct bpf_map *map, __u32 max_entries) return 0; } -static int bpf_object_prepare_token(struct bpf_object *obj) -{ - const char *bpffs_path; - int bpffs_fd = -1, token_fd, err; - bool mandatory; - enum libbpf_print_level level; - - /* token is already set up */ - if (obj->token_fd > 0) - return 0; - /* token is explicitly prevented */ - if (obj->token_fd < 0) { - pr_debug("object '%s': token is prevented, skipping...\n", obj->name); - /* reset to zero to avoid extra checks during map_create and prog_load steps */ - obj->token_fd = 0; - return 0; - } - - mandatory = obj->token_path != NULL; - level = mandatory ? LIBBPF_WARN : LIBBPF_DEBUG; - - bpffs_path = obj->token_path ?: BPF_FS_DEFAULT_PATH; - bpffs_fd = open(bpffs_path, O_DIRECTORY, O_RDWR); - if (bpffs_fd < 0) { - err = -errno; - __pr(level, "object '%s': failed (%d) to open BPF FS mount at '%s'%s\n", - obj->name, err, bpffs_path, - mandatory ? "" : ", skipping optional step..."); - return mandatory ? err : 0; - } - - token_fd = bpf_token_create(bpffs_fd, 0); - close(bpffs_fd); - if (token_fd < 0) { - if (!mandatory && token_fd == -ENOENT) { - pr_debug("object '%s': BPF FS at '%s' doesn't have BPF token delegation set up, skipping...\n", - obj->name, bpffs_path); - return 0; - } - __pr(level, "object '%s': failed (%d) to create BPF token from '%s'%s\n", - obj->name, token_fd, bpffs_path, - mandatory ? "" : ", skipping optional step..."); - return mandatory ? token_fd : 0; - } - - obj->feat_cache = calloc(1, sizeof(*obj->feat_cache)); - if (!obj->feat_cache) { - close(token_fd); - return -ENOMEM; - } - - obj->token_fd = token_fd; - obj->feat_cache->token_fd = token_fd; - - return 0; -} - static int bpf_object__probe_loading(struct bpf_object *obj) { @@ -4674,7 +4611,6 @@ bpf_object__probe_loading(struct bpf_object *obj) BPF_EXIT_INSN(), }; int ret, insn_cnt = ARRAY_SIZE(insns); - LIBBPF_OPTS(bpf_prog_load_opts, opts, .token_fd = obj->token_fd); if (obj->gen_loader) return 0; @@ -4684,9 +4620,9 @@ bpf_object__probe_loading(struct bpf_object *obj) pr_warn("Failed to bump RLIMIT_MEMLOCK (err = %d), you might need to do it explicitly!\n", ret); /* make sure basic loading works */ - ret = bpf_prog_load(BPF_PROG_TYPE_SOCKET_FILTER, NULL, "GPL", insns, insn_cnt, &opts); + ret = bpf_prog_load(BPF_PROG_TYPE_SOCKET_FILTER, NULL, "GPL", insns, insn_cnt, NULL); if (ret < 0) - ret = bpf_prog_load(BPF_PROG_TYPE_TRACEPOINT, NULL, "GPL", insns, insn_cnt, &opts); + ret = bpf_prog_load(BPF_PROG_TYPE_TRACEPOINT, NULL, "GPL", insns, insn_cnt, NULL); if (ret < 0) { ret = errno; cp = libbpf_strerror_r(ret, errmsg, sizeof(errmsg)); @@ -4701,18 +4637,462 @@ bpf_object__probe_loading(struct bpf_object *obj) return 0; } +static int probe_fd(int fd) +{ + if (fd >= 0) + close(fd); + return fd >= 0; +} + +static int probe_kern_prog_name(void) +{ + const size_t attr_sz = offsetofend(union bpf_attr, prog_name); + struct bpf_insn insns[] = { + BPF_MOV64_IMM(BPF_REG_0, 0), + BPF_EXIT_INSN(), + }; + union bpf_attr attr; + int ret; + + memset(&attr, 0, attr_sz); + attr.prog_type = BPF_PROG_TYPE_SOCKET_FILTER; + attr.license = ptr_to_u64("GPL"); + attr.insns = ptr_to_u64(insns); + attr.insn_cnt = (__u32)ARRAY_SIZE(insns); + libbpf_strlcpy(attr.prog_name, "libbpf_nametest", sizeof(attr.prog_name)); + + /* make sure loading with name works */ + ret = sys_bpf_prog_load(&attr, attr_sz, PROG_LOAD_ATTEMPTS); + return probe_fd(ret); +} + +static int probe_kern_global_data(void) +{ + char *cp, errmsg[STRERR_BUFSIZE]; + struct bpf_insn insns[] = { + BPF_LD_MAP_VALUE(BPF_REG_1, 0, 16), + BPF_ST_MEM(BPF_DW, BPF_REG_1, 0, 42), + BPF_MOV64_IMM(BPF_REG_0, 0), + BPF_EXIT_INSN(), + }; + int ret, map, insn_cnt = ARRAY_SIZE(insns); + + map = bpf_map_create(BPF_MAP_TYPE_ARRAY, "libbpf_global", sizeof(int), 32, 1, NULL); + if (map < 0) { + ret = -errno; + cp = libbpf_strerror_r(ret, errmsg, sizeof(errmsg)); + pr_warn("Error in %s():%s(%d). Couldn't create simple array map.\n", + __func__, cp, -ret); + return ret; + } + + insns[0].imm = map; + + ret = bpf_prog_load(BPF_PROG_TYPE_SOCKET_FILTER, NULL, "GPL", insns, insn_cnt, NULL); + close(map); + return probe_fd(ret); +} + +static int probe_kern_btf(void) +{ + static const char strs[] = "\0int"; + __u32 types[] = { + /* int */ + BTF_TYPE_INT_ENC(1, BTF_INT_SIGNED, 0, 32, 4), + }; + + return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types), + strs, sizeof(strs))); +} + +static int probe_kern_btf_func(void) +{ + static const char strs[] = "\0int\0x\0a"; + /* void x(int a) {} */ + __u32 types[] = { + /* int */ + BTF_TYPE_INT_ENC(1, BTF_INT_SIGNED, 0, 32, 4), /* [1] */ + /* FUNC_PROTO */ /* [2] */ + BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_FUNC_PROTO, 0, 1), 0), + BTF_PARAM_ENC(7, 1), + /* FUNC x */ /* [3] */ + BTF_TYPE_ENC(5, BTF_INFO_ENC(BTF_KIND_FUNC, 0, 0), 2), + }; + + return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types), + strs, sizeof(strs))); +} + +static int probe_kern_btf_func_global(void) +{ + static const char strs[] = "\0int\0x\0a"; + /* static void x(int a) {} */ + __u32 types[] = { + /* int */ + BTF_TYPE_INT_ENC(1, BTF_INT_SIGNED, 0, 32, 4), /* [1] */ + /* FUNC_PROTO */ /* [2] */ + BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_FUNC_PROTO, 0, 1), 0), + BTF_PARAM_ENC(7, 1), + /* FUNC x BTF_FUNC_GLOBAL */ /* [3] */ + BTF_TYPE_ENC(5, BTF_INFO_ENC(BTF_KIND_FUNC, 0, BTF_FUNC_GLOBAL), 2), + }; + + return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types), + strs, sizeof(strs))); +} + +static int probe_kern_btf_datasec(void) +{ + static const char strs[] = "\0x\0.data"; + /* static int a; */ + __u32 types[] = { + /* int */ + BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4), /* [1] */ + /* VAR x */ /* [2] */ + BTF_TYPE_ENC(1, BTF_INFO_ENC(BTF_KIND_VAR, 0, 0), 1), + BTF_VAR_STATIC, + /* DATASEC val */ /* [3] */ + BTF_TYPE_ENC(3, BTF_INFO_ENC(BTF_KIND_DATASEC, 0, 1), 4), + BTF_VAR_SECINFO_ENC(2, 0, 4), + }; + + return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types), + strs, sizeof(strs))); +} + +static int probe_kern_btf_float(void) +{ + static const char strs[] = "\0float"; + __u32 types[] = { + /* float */ + BTF_TYPE_FLOAT_ENC(1, 4), + }; + + return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types), + strs, sizeof(strs))); +} + +static int probe_kern_btf_decl_tag(void) +{ + static const char strs[] = "\0tag"; + __u32 types[] = { + /* int */ + BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4), /* [1] */ + /* VAR x */ /* [2] */ + BTF_TYPE_ENC(1, BTF_INFO_ENC(BTF_KIND_VAR, 0, 0), 1), + BTF_VAR_STATIC, + /* attr */ + BTF_TYPE_DECL_TAG_ENC(1, 2, -1), + }; + + return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types), + strs, sizeof(strs))); +} + +static int probe_kern_btf_type_tag(void) +{ + static const char strs[] = "\0tag"; + __u32 types[] = { + /* int */ + BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4), /* [1] */ + /* attr */ + BTF_TYPE_TYPE_TAG_ENC(1, 1), /* [2] */ + /* ptr */ + BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_PTR, 0, 0), 2), /* [3] */ + }; + + return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types), + strs, sizeof(strs))); +} + +static int probe_kern_array_mmap(void) +{ + LIBBPF_OPTS(bpf_map_create_opts, opts, .map_flags = BPF_F_MMAPABLE); + int fd; + + fd = bpf_map_create(BPF_MAP_TYPE_ARRAY, "libbpf_mmap", sizeof(int), sizeof(int), 1, &opts); + return probe_fd(fd); +} + +static int probe_kern_exp_attach_type(void) +{ + LIBBPF_OPTS(bpf_prog_load_opts, opts, .expected_attach_type = BPF_CGROUP_INET_SOCK_CREATE); + struct bpf_insn insns[] = { + BPF_MOV64_IMM(BPF_REG_0, 0), + BPF_EXIT_INSN(), + }; + int fd, insn_cnt = ARRAY_SIZE(insns); + + /* use any valid combination of program type and (optional) + * non-zero expected attach type (i.e., not a BPF_CGROUP_INET_INGRESS) + * to see if kernel supports expected_attach_type field for + * BPF_PROG_LOAD command + */ + fd = bpf_prog_load(BPF_PROG_TYPE_CGROUP_SOCK, NULL, "GPL", insns, insn_cnt, &opts); + return probe_fd(fd); +} + +static int probe_kern_probe_read_kernel(void) +{ + struct bpf_insn insns[] = { + BPF_MOV64_REG(BPF_REG_1, BPF_REG_10), /* r1 = r10 (fp) */ + BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -8), /* r1 += -8 */ + BPF_MOV64_IMM(BPF_REG_2, 8), /* r2 = 8 */ + BPF_MOV64_IMM(BPF_REG_3, 0), /* r3 = 0 */ + BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_probe_read_kernel), + BPF_EXIT_INSN(), + }; + int fd, insn_cnt = ARRAY_SIZE(insns); + + fd = bpf_prog_load(BPF_PROG_TYPE_TRACEPOINT, NULL, "GPL", insns, insn_cnt, NULL); + return probe_fd(fd); +} + +static int probe_prog_bind_map(void) +{ + char *cp, errmsg[STRERR_BUFSIZE]; + struct bpf_insn insns[] = { + BPF_MOV64_IMM(BPF_REG_0, 0), + BPF_EXIT_INSN(), + }; + int ret, map, prog, insn_cnt = ARRAY_SIZE(insns); + + map = bpf_map_create(BPF_MAP_TYPE_ARRAY, "libbpf_det_bind", sizeof(int), 32, 1, NULL); + if (map < 0) { + ret = -errno; + cp = libbpf_strerror_r(ret, errmsg, sizeof(errmsg)); + pr_warn("Error in %s():%s(%d). Couldn't create simple array map.\n", + __func__, cp, -ret); + return ret; + } + + prog = bpf_prog_load(BPF_PROG_TYPE_SOCKET_FILTER, NULL, "GPL", insns, insn_cnt, NULL); + if (prog < 0) { + close(map); + return 0; + } + + ret = bpf_prog_bind_map(prog, map, NULL); + + close(map); + close(prog); + + return ret >= 0; +} + +static int probe_module_btf(void) +{ + static const char strs[] = "\0int"; + __u32 types[] = { + /* int */ + BTF_TYPE_INT_ENC(1, BTF_INT_SIGNED, 0, 32, 4), + }; + struct bpf_btf_info info; + __u32 len = sizeof(info); + char name[16]; + int fd, err; + + fd = libbpf__load_raw_btf((char *)types, sizeof(types), strs, sizeof(strs)); + if (fd < 0) + return 0; /* BTF not supported at all */ + + memset(&info, 0, sizeof(info)); + info.name = ptr_to_u64(name); + info.name_len = sizeof(name); + + /* check that BPF_OBJ_GET_INFO_BY_FD supports specifying name pointer; + * kernel's module BTF support coincides with support for + * name/name_len fields in struct bpf_btf_info. + */ + err = bpf_btf_get_info_by_fd(fd, &info, &len); + close(fd); + return !err; +} + +static int probe_perf_link(void) +{ + struct bpf_insn insns[] = { + BPF_MOV64_IMM(BPF_REG_0, 0), + BPF_EXIT_INSN(), + }; + int prog_fd, link_fd, err; + + prog_fd = bpf_prog_load(BPF_PROG_TYPE_TRACEPOINT, NULL, "GPL", + insns, ARRAY_SIZE(insns), NULL); + if (prog_fd < 0) + return -errno; + + /* use invalid perf_event FD to get EBADF, if link is supported; + * otherwise EINVAL should be returned + */ + link_fd = bpf_link_create(prog_fd, -1, BPF_PERF_EVENT, NULL); + err = -errno; /* close() can clobber errno */ + + if (link_fd >= 0) + close(link_fd); + close(prog_fd); + + return link_fd < 0 && err == -EBADF; +} + +static int probe_uprobe_multi_link(void) +{ + LIBBPF_OPTS(bpf_prog_load_opts, load_opts, + .expected_attach_type = BPF_TRACE_UPROBE_MULTI, + ); + LIBBPF_OPTS(bpf_link_create_opts, link_opts); + struct bpf_insn insns[] = { + BPF_MOV64_IMM(BPF_REG_0, 0), + BPF_EXIT_INSN(), + }; + int prog_fd, link_fd, err; + unsigned long offset = 0; + + prog_fd = bpf_prog_load(BPF_PROG_TYPE_KPROBE, NULL, "GPL", + insns, ARRAY_SIZE(insns), &load_opts); + if (prog_fd < 0) + return -errno; + + /* Creating uprobe in '/' binary should fail with -EBADF. */ + link_opts.uprobe_multi.path = "/"; + link_opts.uprobe_multi.offsets = &offset; + link_opts.uprobe_multi.cnt = 1; + + link_fd = bpf_link_create(prog_fd, -1, BPF_TRACE_UPROBE_MULTI, &link_opts); + err = -errno; /* close() can clobber errno */ + + if (link_fd >= 0) + close(link_fd); + close(prog_fd); + + return link_fd < 0 && err == -EBADF; +} + +static int probe_kern_bpf_cookie(void) +{ + struct bpf_insn insns[] = { + BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_get_attach_cookie), + BPF_EXIT_INSN(), + }; + int ret, insn_cnt = ARRAY_SIZE(insns); + + ret = bpf_prog_load(BPF_PROG_TYPE_KPROBE, NULL, "GPL", insns, insn_cnt, NULL); + return probe_fd(ret); +} + +static int probe_kern_btf_enum64(void) +{ + static const char strs[] = "\0enum64"; + __u32 types[] = { + BTF_TYPE_ENC(1, BTF_INFO_ENC(BTF_KIND_ENUM64, 0, 0), 8), + }; + + return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types), + strs, sizeof(strs))); +} + +static int probe_kern_syscall_wrapper(void); + +enum kern_feature_result { + FEAT_UNKNOWN = 0, + FEAT_SUPPORTED = 1, + FEAT_MISSING = 2, +}; + +typedef int (*feature_probe_fn)(void); + +static struct kern_feature_desc { + const char *desc; + feature_probe_fn probe; + enum kern_feature_result res; +} feature_probes[__FEAT_CNT] = { + [FEAT_PROG_NAME] = { + "BPF program name", probe_kern_prog_name, + }, + [FEAT_GLOBAL_DATA] = { + "global variables", probe_kern_global_data, + }, + [FEAT_BTF] = { + "minimal BTF", probe_kern_btf, + }, + [FEAT_BTF_FUNC] = { + "BTF functions", probe_kern_btf_func, + }, + [FEAT_BTF_GLOBAL_FUNC] = { + "BTF global function", probe_kern_btf_func_global, + }, + [FEAT_BTF_DATASEC] = { + "BTF data section and variable", probe_kern_btf_datasec, + }, + [FEAT_ARRAY_MMAP] = { + "ARRAY map mmap()", probe_kern_array_mmap, + }, + [FEAT_EXP_ATTACH_TYPE] = { + "BPF_PROG_LOAD expected_attach_type attribute", + probe_kern_exp_attach_type, + }, + [FEAT_PROBE_READ_KERN] = { + "bpf_probe_read_kernel() helper", probe_kern_probe_read_kernel, + }, + [FEAT_PROG_BIND_MAP] = { + "BPF_PROG_BIND_MAP support", probe_prog_bind_map, + }, + [FEAT_MODULE_BTF] = { + "module BTF support", probe_module_btf, + }, + [FEAT_BTF_FLOAT] = { + "BTF_KIND_FLOAT support", probe_kern_btf_float, + }, + [FEAT_PERF_LINK] = { + "BPF perf link support", probe_perf_link, + }, + [FEAT_BTF_DECL_TAG] = { + "BTF_KIND_DECL_TAG support", probe_kern_btf_decl_tag, + }, + [FEAT_BTF_TYPE_TAG] = { + "BTF_KIND_TYPE_TAG support", probe_kern_btf_type_tag, + }, + [FEAT_MEMCG_ACCOUNT] = { + "memcg-based memory accounting", probe_memcg_account, + }, + [FEAT_BPF_COOKIE] = { + "BPF cookie support", probe_kern_bpf_cookie, + }, + [FEAT_BTF_ENUM64] = { + "BTF_KIND_ENUM64 support", probe_kern_btf_enum64, + }, + [FEAT_SYSCALL_WRAPPER] = { + "Kernel using syscall wrapper", probe_kern_syscall_wrapper, + }, + [FEAT_UPROBE_MULTI_LINK] = { + "BPF multi-uprobe link support", probe_uprobe_multi_link, + }, +}; + bool kernel_supports(const struct bpf_object *obj, enum kern_feature_id feat_id) { + struct kern_feature_desc *feat = &feature_probes[feat_id]; + int ret; + if (obj && obj->gen_loader) /* To generate loader program assume the latest kernel * to avoid doing extra prog_load, map_create syscalls. */ return true; - if (obj->token_fd) - return feat_supported(obj->feat_cache, feat_id); + if (READ_ONCE(feat->res) == FEAT_UNKNOWN) { + ret = feat->probe(); + if (ret > 0) { + WRITE_ONCE(feat->res, FEAT_SUPPORTED); + } else if (ret == 0) { + WRITE_ONCE(feat->res, FEAT_MISSING); + } else { + pr_warn("Detection of kernel %s support failed: %d\n", feat->desc, ret); + WRITE_ONCE(feat->res, FEAT_MISSING); + } + } - return feat_supported(NULL, feat_id); + return READ_ONCE(feat->res) == FEAT_SUPPORTED; } static bool map_is_reuse_compat(const struct bpf_map *map, int map_fd) @@ -4831,7 +5211,6 @@ static int bpf_object__create_map(struct bpf_object *obj, struct bpf_map *map, b create_attr.map_flags = def->map_flags; create_attr.numa_node = map->numa_node; create_attr.map_extra = map->map_extra; - create_attr.token_fd = obj->token_fd; if (bpf_map__is_struct_ops(map)) create_attr.btf_vmlinux_value_type_id = map->btf_vmlinux_value_type_id; @@ -6667,7 +7046,6 @@ static int bpf_object_load_prog(struct bpf_object *obj, struct bpf_program *prog load_attr.attach_btf_id = prog->attach_btf_id; load_attr.kern_version = kern_version; load_attr.prog_ifindex = prog->prog_ifindex; - load_attr.token_fd = obj->token_fd; /* specify func_info/line_info only if kernel supports them */ btf_fd = bpf_object__btf_fd(obj); @@ -7129,10 +7507,10 @@ static int bpf_object_init_progs(struct bpf_object *obj, const struct bpf_object static struct bpf_object *bpf_object_open(const char *path, const void *obj_buf, size_t obj_buf_sz, const struct bpf_object_open_opts *opts) { - const char *obj_name, *kconfig, *btf_tmp_path, *token_path; + const char *obj_name, *kconfig, *btf_tmp_path; struct bpf_object *obj; char tmp_name[64]; - int err, token_fd; + int err; char *log_buf; size_t log_size; __u32 log_level; @@ -7166,28 +7544,6 @@ static struct bpf_object *bpf_object_open(const char *path, const void *obj_buf, if (log_size && !log_buf) return ERR_PTR(-EINVAL); - token_path = OPTS_GET(opts, bpf_token_path, NULL); - token_fd = OPTS_GET(opts, bpf_token_fd, -1); - /* non-empty token path can't be combined with invalid token FD */ - if (token_path && token_path[0] != '\0' && token_fd < 0) - return ERR_PTR(-EINVAL); - /* empty token path can't be combined with valid token FD */ - if (token_path && token_path[0] == '\0' && token_fd > 0) - return ERR_PTR(-EINVAL); - /* if user didn't specify bpf_token_path/bpf_token_fd explicitly, - * check if LIBBPF_BPF_TOKEN_PATH envvar was set and treat it as - * bpf_token_path option - */ - if (token_fd == 0 && !token_path) - token_path = getenv("LIBBPF_BPF_TOKEN_PATH"); - /* empty token_path is equivalent to invalid token_fd */ - if (token_path && token_path[0] == '\0') { - token_path = NULL; - token_fd = -1; - } - if (token_path && strlen(token_path) >= PATH_MAX) - return ERR_PTR(-ENAMETOOLONG); - obj = bpf_object__new(path, obj_buf, obj_buf_sz, obj_name); if (IS_ERR(obj)) return obj; @@ -7196,19 +7552,6 @@ static struct bpf_object *bpf_object_open(const char *path, const void *obj_buf, obj->log_size = log_size; obj->log_level = log_level; - obj->token_fd = token_fd <= 0 ? token_fd : dup_good_fd(token_fd); - if (token_fd > 0 && obj->token_fd < 0) { - err = -errno; - goto out; - } - if (token_path) { - obj->token_path = strdup(token_path); - if (!obj->token_path) { - err = -ENOMEM; - goto out; - } - } - btf_tmp_path = OPTS_GET(opts, btf_custom_path, NULL); if (btf_tmp_path) { if (strlen(btf_tmp_path) >= PATH_MAX) { @@ -7719,8 +8062,7 @@ static int bpf_object_load(struct bpf_object *obj, int extra_log_level, const ch if (obj->gen_loader) bpf_gen__init(obj->gen_loader, extra_log_level, obj->nr_programs, obj->nr_maps); - err = bpf_object_prepare_token(obj); - err = err ? : bpf_object__probe_loading(obj); + err = bpf_object__probe_loading(obj); err = err ? : bpf_object__load_vmlinux_btf(obj, false); err = err ? : bpf_object__resolve_externs(obj, obj->kconfig); err = err ? : bpf_object__sanitize_and_load_btf(obj); @@ -8257,11 +8599,6 @@ void bpf_object__close(struct bpf_object *obj) } zfree(&obj->programs); - zfree(&obj->feat_cache); - zfree(&obj->token_path); - if (obj->token_fd > 0) - close(obj->token_fd); - free(obj); } @@ -10275,7 +10612,7 @@ static const char *arch_specific_syscall_pfx(void) #endif } -int probe_kern_syscall_wrapper(int token_fd) +static int probe_kern_syscall_wrapper(void) { char syscall_name[64]; const char *ksys_pfx; diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h index 916904bd2a7a..6cd9c501624f 100644 --- a/tools/lib/bpf/libbpf.h +++ b/tools/lib/bpf/libbpf.h @@ -177,45 +177,10 @@ struct bpf_object_open_opts { * logs through its print callback. */ __u32 kernel_log_level; - /* FD of a BPF token instantiated by user through bpf_token_create() - * API. BPF object will keep dup()'ed FD internally, so passed token - * FD can be closed after BPF object/skeleton open step. - * - * Setting bpf_token_fd to negative value disables libbpf's automatic - * attempt to create BPF token from default BPF FS mount point - * (/sys/fs/bpf), in case this default behavior is undesirable. - * - * If bpf_token_path and bpf_token_fd are not specified, libbpf will - * consult LIBBPF_BPF_TOKEN_PATH environment variable. If set, it will - * be taken as a value of bpf_token_path option and will force libbpf - * to either create BPF token from provided custom BPF FS path, or - * will disable implicit BPF token creation, if envvar value is an - * empty string. - * - * bpf_token_path and bpf_token_fd are mutually exclusive and only one - * of those options should be set. Either of them overrides - * LIBBPF_BPF_TOKEN_PATH envvar. - */ - int bpf_token_fd; - /* Path to BPF FS mount point to derive BPF token from. - * - * Created BPF token will be used for all bpf() syscall operations - * that accept BPF token (e.g., map creation, BTF and program loads, - * etc) automatically within instantiated BPF object. - * - * Setting bpf_token_path option to empty string disables libbpf's - * automatic attempt to create BPF token from default BPF FS mount - * point (/sys/fs/bpf), in case this default behavior is undesirable. - * - * bpf_token_path and bpf_token_fd are mutually exclusive and only one - * of those options should be set. Either of them overrides - * LIBBPF_BPF_TOKEN_PATH envvar. - */ - const char *bpf_token_path; size_t :0; }; -#define bpf_object_open_opts__last_field bpf_token_path +#define bpf_object_open_opts__last_field kernel_log_level /** * @brief **bpf_object__open()** creates a bpf_object by opening diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map index df7657b65c47..91c5aef7dae7 100644 --- a/tools/lib/bpf/libbpf.map +++ b/tools/lib/bpf/libbpf.map @@ -401,7 +401,6 @@ LIBBPF_1.3.0 { bpf_program__attach_netkit; bpf_program__attach_tcx; bpf_program__attach_uprobe_multi; - bpf_token_create; ring__avail_data_size; ring__consume; ring__consumer_pos; diff --git a/tools/lib/bpf/libbpf_internal.h b/tools/lib/bpf/libbpf_internal.h index 4cda32298c49..b5d334754e5d 100644 --- a/tools/lib/bpf/libbpf_internal.h +++ b/tools/lib/bpf/libbpf_internal.h @@ -360,32 +360,15 @@ enum kern_feature_id { __FEAT_CNT, }; -enum kern_feature_result { - FEAT_UNKNOWN = 0, - FEAT_SUPPORTED = 1, - FEAT_MISSING = 2, -}; - -struct kern_feature_cache { - enum kern_feature_result res[__FEAT_CNT]; - int token_fd; -}; - -bool feat_supported(struct kern_feature_cache *cache, enum kern_feature_id feat_id); +int probe_memcg_account(void); bool kernel_supports(const struct bpf_object *obj, enum kern_feature_id feat_id); - -int probe_kern_syscall_wrapper(int token_fd); -int probe_memcg_account(int token_fd); int bump_rlimit_memlock(void); int parse_cpu_mask_str(const char *s, bool **mask, int *mask_sz); int parse_cpu_mask_file(const char *fcpu, bool **mask, int *mask_sz); int libbpf__load_raw_btf(const char *raw_types, size_t types_len, - const char *str_sec, size_t str_len, - int token_fd); -int btf_load_into_kernel(struct btf *btf, - char *log_buf, size_t log_sz, __u32 log_level, - int token_fd); + const char *str_sec, size_t str_len); +int btf_load_into_kernel(struct btf *btf, char *log_buf, size_t log_sz, __u32 log_level); struct btf *btf_get_from_fd(int btf_fd, struct btf *base_btf); void btf_get_kernel_prefix_kind(enum bpf_attach_type attach_type, @@ -549,17 +532,6 @@ static inline bool is_ldimm64_insn(struct bpf_insn *insn) return insn->code == (BPF_LD | BPF_IMM | BPF_DW); } -/* Unconditionally dup FD, ensuring it doesn't use [0, 2] range. - * Original FD is not closed or altered in any other way. - * Preserves original FD value, if it's invalid (negative). - */ -static inline int dup_good_fd(int fd) -{ - if (fd < 0) - return fd; - return fcntl(fd, F_DUPFD_CLOEXEC, 3); -} - /* if fd is stdin, stdout, or stderr, dup to a fd greater than 2 * Takes ownership of the fd passed in, and closes it if calling * fcntl(fd, F_DUPFD_CLOEXEC, 3). @@ -571,7 +543,7 @@ static inline int ensure_good_fd(int fd) if (fd < 0) return fd; if (fd < 3) { - fd = dup_good_fd(fd); + fd = fcntl(fd, F_DUPFD_CLOEXEC, 3); saved_errno = errno; close(old_fd); errno = saved_errno; diff --git a/tools/lib/bpf/libbpf_probes.c b/tools/lib/bpf/libbpf_probes.c index 8e7437006639..9c4db90b92b6 100644 --- a/tools/lib/bpf/libbpf_probes.c +++ b/tools/lib/bpf/libbpf_probes.c @@ -219,8 +219,7 @@ int libbpf_probe_bpf_prog_type(enum bpf_prog_type prog_type, const void *opts) } int libbpf__load_raw_btf(const char *raw_types, size_t types_len, - const char *str_sec, size_t str_len, - int token_fd) + const char *str_sec, size_t str_len) { struct btf_header hdr = { .magic = BTF_MAGIC, @@ -230,7 +229,6 @@ int libbpf__load_raw_btf(const char *raw_types, size_t types_len, .str_off = types_len, .str_len = str_len, }; - LIBBPF_OPTS(bpf_btf_load_opts, opts, .token_fd = token_fd); int btf_fd, btf_len; __u8 *raw_btf; @@ -243,7 +241,7 @@ int libbpf__load_raw_btf(const char *raw_types, size_t types_len, memcpy(raw_btf + hdr.hdr_len, raw_types, hdr.type_len); memcpy(raw_btf + hdr.hdr_len + hdr.type_len, str_sec, hdr.str_len); - btf_fd = bpf_btf_load(raw_btf, btf_len, &opts); + btf_fd = bpf_btf_load(raw_btf, btf_len, NULL); free(raw_btf); return btf_fd; @@ -273,7 +271,7 @@ static int load_local_storage_btf(void) }; return libbpf__load_raw_btf((char *)types, sizeof(types), - strs, sizeof(strs), 0); + strs, sizeof(strs)); } static int probe_map_create(enum bpf_map_type map_type) diff --git a/tools/lib/bpf/str_error.h b/tools/lib/bpf/str_error.h index 626d7ffb03d6..a139334d57b6 100644 --- a/tools/lib/bpf/str_error.h +++ b/tools/lib/bpf/str_error.h @@ -2,8 +2,5 @@ #ifndef __LIBBPF_STR_ERROR_H #define __LIBBPF_STR_ERROR_H -#define STRERR_BUFSIZE 128 - char *libbpf_strerror_r(int err, char *dst, int len); - #endif /* __LIBBPF_STR_ERROR_H */ diff --git a/tools/testing/selftests/bpf/prog_tests/libbpf_probes.c b/tools/testing/selftests/bpf/prog_tests/libbpf_probes.c index 4ed46ed58a7b..9f766ddd946a 100644 --- a/tools/testing/selftests/bpf/prog_tests/libbpf_probes.c +++ b/tools/testing/selftests/bpf/prog_tests/libbpf_probes.c @@ -30,8 +30,6 @@ void test_libbpf_probe_prog_types(void) if (prog_type == BPF_PROG_TYPE_UNSPEC) continue; - if (strcmp(prog_type_name, "__MAX_BPF_PROG_TYPE") == 0) - continue; if (!test__start_subtest(prog_type_name)) continue; @@ -70,8 +68,6 @@ void test_libbpf_probe_map_types(void) if (map_type == BPF_MAP_TYPE_UNSPEC) continue; - if (strcmp(map_type_name, "__MAX_BPF_MAP_TYPE") == 0) - continue; if (!test__start_subtest(map_type_name)) continue; diff --git a/tools/testing/selftests/bpf/prog_tests/libbpf_str.c b/tools/testing/selftests/bpf/prog_tests/libbpf_str.c index 62ea855ec4d0..eb34d612d6f8 100644 --- a/tools/testing/selftests/bpf/prog_tests/libbpf_str.c +++ b/tools/testing/selftests/bpf/prog_tests/libbpf_str.c @@ -132,9 +132,6 @@ static void test_libbpf_bpf_map_type_str(void) const char *map_type_str; char buf[256]; - if (map_type == __MAX_BPF_MAP_TYPE) - continue; - map_type_name = btf__str_by_offset(btf, e->name_off); map_type_str = libbpf_bpf_map_type_str(map_type); ASSERT_OK_PTR(map_type_str, map_type_name); @@ -189,9 +186,6 @@ static void test_libbpf_bpf_prog_type_str(void) const char *prog_type_str; char buf[256]; - if (prog_type == __MAX_BPF_PROG_TYPE) - continue; - prog_type_name = btf__str_by_offset(btf, e->name_off); prog_type_str = libbpf_bpf_prog_type_str(prog_type); ASSERT_OK_PTR(prog_type_str, prog_type_name); diff --git a/tools/testing/selftests/bpf/prog_tests/token.c b/tools/testing/selftests/bpf/prog_tests/token.c deleted file mode 100644 index b5dce630e0e1..000000000000 --- a/tools/testing/selftests/bpf/prog_tests/token.c +++ /dev/null @@ -1,1031 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -/* Copyright (c) 2023 Meta Platforms, Inc. and affiliates. */ -#define _GNU_SOURCE -#include -#include -#include "cap_helpers.h" -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include "priv_map.skel.h" -#include "priv_prog.skel.h" -#include "dummy_st_ops_success.skel.h" - -static inline int sys_mount(const char *dev_name, const char *dir_name, - const char *type, unsigned long flags, - const void *data) -{ - return syscall(__NR_mount, dev_name, dir_name, type, flags, data); -} - -static inline int sys_fsopen(const char *fsname, unsigned flags) -{ - return syscall(__NR_fsopen, fsname, flags); -} - -static inline int sys_fspick(int dfd, const char *path, unsigned flags) -{ - return syscall(__NR_fspick, dfd, path, flags); -} - -static inline int sys_fsconfig(int fs_fd, unsigned cmd, const char *key, const void *val, int aux) -{ - return syscall(__NR_fsconfig, fs_fd, cmd, key, val, aux); -} - -static inline int sys_fsmount(int fs_fd, unsigned flags, unsigned ms_flags) -{ - return syscall(__NR_fsmount, fs_fd, flags, ms_flags); -} - -static inline int sys_move_mount(int from_dfd, const char *from_path, - int to_dfd, const char *to_path, - unsigned flags) -{ - return syscall(__NR_move_mount, from_dfd, from_path, to_dfd, to_path, flags); -} - -static int drop_priv_caps(__u64 *old_caps) -{ - return cap_disable_effective((1ULL << CAP_BPF) | - (1ULL << CAP_PERFMON) | - (1ULL << CAP_NET_ADMIN) | - (1ULL << CAP_SYS_ADMIN), old_caps); -} - -static int restore_priv_caps(__u64 old_caps) -{ - return cap_enable_effective(old_caps, NULL); -} - -static int set_delegate_mask(int fs_fd, const char *key, __u64 mask, const char *mask_str) -{ - char buf[32]; - int err; - - if (!mask_str) { - if (mask == ~0ULL) { - mask_str = "any"; - } else { - snprintf(buf, sizeof(buf), "0x%llx", (unsigned long long)mask); - mask_str = buf; - } - } - - err = sys_fsconfig(fs_fd, FSCONFIG_SET_STRING, key, - mask_str, 0); - if (err < 0) - err = -errno; - return err; -} - -#define zclose(fd) do { if (fd >= 0) close(fd); fd = -1; } while (0) - -struct bpffs_opts { - __u64 cmds; - __u64 maps; - __u64 progs; - __u64 attachs; - const char *cmds_str; - const char *maps_str; - const char *progs_str; - const char *attachs_str; -}; - -static int create_bpffs_fd(void) -{ - int fs_fd; - - /* create VFS context */ - fs_fd = sys_fsopen("bpf", 0); - ASSERT_GE(fs_fd, 0, "fs_fd"); - - return fs_fd; -} - -static int materialize_bpffs_fd(int fs_fd, struct bpffs_opts *opts) -{ - int mnt_fd, err; - - /* set up token delegation mount options */ - err = set_delegate_mask(fs_fd, "delegate_cmds", opts->cmds, opts->cmds_str); - if (!ASSERT_OK(err, "fs_cfg_cmds")) - return err; - err = set_delegate_mask(fs_fd, "delegate_maps", opts->maps, opts->maps_str); - if (!ASSERT_OK(err, "fs_cfg_maps")) - return err; - err = set_delegate_mask(fs_fd, "delegate_progs", opts->progs, opts->progs_str); - if (!ASSERT_OK(err, "fs_cfg_progs")) - return err; - err = set_delegate_mask(fs_fd, "delegate_attachs", opts->attachs, opts->attachs_str); - if (!ASSERT_OK(err, "fs_cfg_attachs")) - return err; - - /* instantiate FS object */ - err = sys_fsconfig(fs_fd, FSCONFIG_CMD_CREATE, NULL, NULL, 0); - if (err < 0) - return -errno; - - /* create O_PATH fd for detached mount */ - mnt_fd = sys_fsmount(fs_fd, 0, 0); - if (err < 0) - return -errno; - - return mnt_fd; -} - -/* send FD over Unix domain (AF_UNIX) socket */ -static int sendfd(int sockfd, int fd) -{ - struct msghdr msg = {}; - struct cmsghdr *cmsg; - int fds[1] = { fd }, err; - char iobuf[1]; - struct iovec io = { - .iov_base = iobuf, - .iov_len = sizeof(iobuf), - }; - union { - char buf[CMSG_SPACE(sizeof(fds))]; - struct cmsghdr align; - } u; - - msg.msg_iov = &io; - msg.msg_iovlen = 1; - msg.msg_control = u.buf; - msg.msg_controllen = sizeof(u.buf); - cmsg = CMSG_FIRSTHDR(&msg); - cmsg->cmsg_level = SOL_SOCKET; - cmsg->cmsg_type = SCM_RIGHTS; - cmsg->cmsg_len = CMSG_LEN(sizeof(fds)); - memcpy(CMSG_DATA(cmsg), fds, sizeof(fds)); - - err = sendmsg(sockfd, &msg, 0); - if (err < 0) - err = -errno; - if (!ASSERT_EQ(err, 1, "sendmsg")) - return -EINVAL; - - return 0; -} - -/* receive FD over Unix domain (AF_UNIX) socket */ -static int recvfd(int sockfd, int *fd) -{ - struct msghdr msg = {}; - struct cmsghdr *cmsg; - int fds[1], err; - char iobuf[1]; - struct iovec io = { - .iov_base = iobuf, - .iov_len = sizeof(iobuf), - }; - union { - char buf[CMSG_SPACE(sizeof(fds))]; - struct cmsghdr align; - } u; - - msg.msg_iov = &io; - msg.msg_iovlen = 1; - msg.msg_control = u.buf; - msg.msg_controllen = sizeof(u.buf); - - err = recvmsg(sockfd, &msg, 0); - if (err < 0) - err = -errno; - if (!ASSERT_EQ(err, 1, "recvmsg")) - return -EINVAL; - - cmsg = CMSG_FIRSTHDR(&msg); - if (!ASSERT_OK_PTR(cmsg, "cmsg_null") || - !ASSERT_EQ(cmsg->cmsg_len, CMSG_LEN(sizeof(fds)), "cmsg_len") || - !ASSERT_EQ(cmsg->cmsg_level, SOL_SOCKET, "cmsg_level") || - !ASSERT_EQ(cmsg->cmsg_type, SCM_RIGHTS, "cmsg_type")) - return -EINVAL; - - memcpy(fds, CMSG_DATA(cmsg), sizeof(fds)); - *fd = fds[0]; - - return 0; -} - -static ssize_t write_nointr(int fd, const void *buf, size_t count) -{ - ssize_t ret; - - do { - ret = write(fd, buf, count); - } while (ret < 0 && errno == EINTR); - - return ret; -} - -static int write_file(const char *path, const void *buf, size_t count) -{ - int fd; - ssize_t ret; - - fd = open(path, O_WRONLY | O_CLOEXEC | O_NOCTTY | O_NOFOLLOW); - if (fd < 0) - return -1; - - ret = write_nointr(fd, buf, count); - close(fd); - if (ret < 0 || (size_t)ret != count) - return -1; - - return 0; -} - -static int create_and_enter_userns(void) -{ - uid_t uid; - gid_t gid; - char map[100]; - - uid = getuid(); - gid = getgid(); - - if (unshare(CLONE_NEWUSER)) - return -1; - - if (write_file("/proc/self/setgroups", "deny", sizeof("deny") - 1) && - errno != ENOENT) - return -1; - - snprintf(map, sizeof(map), "0 %d 1", uid); - if (write_file("/proc/self/uid_map", map, strlen(map))) - return -1; - - - snprintf(map, sizeof(map), "0 %d 1", gid); - if (write_file("/proc/self/gid_map", map, strlen(map))) - return -1; - - if (setgid(0)) - return -1; - - if (setuid(0)) - return -1; - - return 0; -} - -typedef int (*child_callback_fn)(int); - -static void child(int sock_fd, struct bpffs_opts *opts, child_callback_fn callback) -{ - LIBBPF_OPTS(bpf_map_create_opts, map_opts); - int mnt_fd = -1, fs_fd = -1, err = 0, bpffs_fd = -1; - - /* setup userns with root mappings */ - err = create_and_enter_userns(); - if (!ASSERT_OK(err, "create_and_enter_userns")) - goto cleanup; - - /* setup mountns to allow creating BPF FS (fsopen("bpf")) from unpriv process */ - err = unshare(CLONE_NEWNS); - if (!ASSERT_OK(err, "create_mountns")) - goto cleanup; - - err = sys_mount(NULL, "/", NULL, MS_REC | MS_PRIVATE, 0); - if (!ASSERT_OK(err, "remount_root")) - goto cleanup; - - fs_fd = create_bpffs_fd(); - if (!ASSERT_GE(fs_fd, 0, "create_bpffs_fd")) { - err = -EINVAL; - goto cleanup; - } - - /* ensure unprivileged child cannot set delegation options */ - err = set_delegate_mask(fs_fd, "delegate_cmds", 0x1, NULL); - ASSERT_EQ(err, -EPERM, "delegate_cmd_eperm"); - err = set_delegate_mask(fs_fd, "delegate_maps", 0x1, NULL); - ASSERT_EQ(err, -EPERM, "delegate_maps_eperm"); - err = set_delegate_mask(fs_fd, "delegate_progs", 0x1, NULL); - ASSERT_EQ(err, -EPERM, "delegate_progs_eperm"); - err = set_delegate_mask(fs_fd, "delegate_attachs", 0x1, NULL); - ASSERT_EQ(err, -EPERM, "delegate_attachs_eperm"); - - /* pass BPF FS context object to parent */ - err = sendfd(sock_fd, fs_fd); - if (!ASSERT_OK(err, "send_fs_fd")) - goto cleanup; - zclose(fs_fd); - - /* avoid mucking around with mount namespaces and mounting at - * well-known path, just get detach-mounted BPF FS fd back from parent - */ - err = recvfd(sock_fd, &mnt_fd); - if (!ASSERT_OK(err, "recv_mnt_fd")) - goto cleanup; - - /* try to fspick() BPF FS and try to add some delegation options */ - fs_fd = sys_fspick(mnt_fd, "", FSPICK_EMPTY_PATH); - if (!ASSERT_GE(fs_fd, 0, "bpffs_fspick")) { - err = -EINVAL; - goto cleanup; - } - - /* ensure unprivileged child cannot reconfigure to set delegation options */ - err = set_delegate_mask(fs_fd, "delegate_cmds", 0, "any"); - if (!ASSERT_EQ(err, -EPERM, "delegate_cmd_eperm_reconfig")) { - err = -EINVAL; - goto cleanup; - } - err = set_delegate_mask(fs_fd, "delegate_maps", 0, "any"); - if (!ASSERT_EQ(err, -EPERM, "delegate_maps_eperm_reconfig")) { - err = -EINVAL; - goto cleanup; - } - err = set_delegate_mask(fs_fd, "delegate_progs", 0, "any"); - if (!ASSERT_EQ(err, -EPERM, "delegate_progs_eperm_reconfig")) { - err = -EINVAL; - goto cleanup; - } - err = set_delegate_mask(fs_fd, "delegate_attachs", 0, "any"); - if (!ASSERT_EQ(err, -EPERM, "delegate_attachs_eperm_reconfig")) { - err = -EINVAL; - goto cleanup; - } - zclose(fs_fd); - - bpffs_fd = openat(mnt_fd, ".", 0, O_RDWR); - if (!ASSERT_GE(bpffs_fd, 0, "bpffs_open")) { - err = -EINVAL; - goto cleanup; - } - - /* do custom test logic with customly set up BPF FS instance */ - err = callback(bpffs_fd); - if (!ASSERT_OK(err, "test_callback")) - goto cleanup; - - err = 0; -cleanup: - zclose(sock_fd); - zclose(mnt_fd); - zclose(fs_fd); - zclose(bpffs_fd); - - exit(-err); -} - -static int wait_for_pid(pid_t pid) -{ - int status, ret; - -again: - ret = waitpid(pid, &status, 0); - if (ret == -1) { - if (errno == EINTR) - goto again; - - return -1; - } - - if (!WIFEXITED(status)) - return -1; - - return WEXITSTATUS(status); -} - -static void parent(int child_pid, struct bpffs_opts *bpffs_opts, int sock_fd) -{ - int fs_fd = -1, mnt_fd = -1, err; - - err = recvfd(sock_fd, &fs_fd); - if (!ASSERT_OK(err, "recv_bpffs_fd")) - goto cleanup; - - mnt_fd = materialize_bpffs_fd(fs_fd, bpffs_opts); - if (!ASSERT_GE(mnt_fd, 0, "materialize_bpffs_fd")) { - err = -EINVAL; - goto cleanup; - } - zclose(fs_fd); - - /* pass BPF FS context object to parent */ - err = sendfd(sock_fd, mnt_fd); - if (!ASSERT_OK(err, "send_mnt_fd")) - goto cleanup; - zclose(mnt_fd); - - err = wait_for_pid(child_pid); - ASSERT_OK(err, "waitpid_child"); - -cleanup: - zclose(sock_fd); - zclose(fs_fd); - zclose(mnt_fd); - - if (child_pid > 0) - (void)kill(child_pid, SIGKILL); -} - -static void subtest_userns(struct bpffs_opts *bpffs_opts, child_callback_fn cb) -{ - int sock_fds[2] = { -1, -1 }; - int child_pid = 0, err; - - err = socketpair(AF_UNIX, SOCK_STREAM, 0, sock_fds); - if (!ASSERT_OK(err, "socketpair")) - goto cleanup; - - child_pid = fork(); - if (!ASSERT_GE(child_pid, 0, "fork")) - goto cleanup; - - if (child_pid == 0) { - zclose(sock_fds[0]); - return child(sock_fds[1], bpffs_opts, cb); - - } else { - zclose(sock_fds[1]); - return parent(child_pid, bpffs_opts, sock_fds[0]); - } - -cleanup: - zclose(sock_fds[0]); - zclose(sock_fds[1]); - if (child_pid > 0) - (void)kill(child_pid, SIGKILL); -} - -static int userns_map_create(int mnt_fd) -{ - LIBBPF_OPTS(bpf_map_create_opts, map_opts); - int err, token_fd = -1, map_fd = -1; - __u64 old_caps = 0; - - /* create BPF token from BPF FS mount */ - token_fd = bpf_token_create(mnt_fd, NULL); - if (!ASSERT_GT(token_fd, 0, "token_create")) { - err = -EINVAL; - goto cleanup; - } - - /* while inside non-init userns, we need both a BPF token *and* - * CAP_BPF inside current userns to create privileged map; let's test - * that neither BPF token alone nor namespaced CAP_BPF is sufficient - */ - err = drop_priv_caps(&old_caps); - if (!ASSERT_OK(err, "drop_caps")) - goto cleanup; - - /* no token, no CAP_BPF -> fail */ - map_opts.token_fd = 0; - map_fd = bpf_map_create(BPF_MAP_TYPE_STACK, "wo_token_wo_bpf", 0, 8, 1, &map_opts); - if (!ASSERT_LT(map_fd, 0, "stack_map_wo_token_wo_cap_bpf_should_fail")) { - err = -EINVAL; - goto cleanup; - } - - /* token without CAP_BPF -> fail */ - map_opts.token_fd = token_fd; - map_fd = bpf_map_create(BPF_MAP_TYPE_STACK, "w_token_wo_bpf", 0, 8, 1, &map_opts); - if (!ASSERT_LT(map_fd, 0, "stack_map_w_token_wo_cap_bpf_should_fail")) { - err = -EINVAL; - goto cleanup; - } - - /* get back effective local CAP_BPF (and CAP_SYS_ADMIN) */ - err = restore_priv_caps(old_caps); - if (!ASSERT_OK(err, "restore_caps")) - goto cleanup; - - /* CAP_BPF without token -> fail */ - map_opts.token_fd = 0; - map_fd = bpf_map_create(BPF_MAP_TYPE_STACK, "wo_token_w_bpf", 0, 8, 1, &map_opts); - if (!ASSERT_LT(map_fd, 0, "stack_map_wo_token_w_cap_bpf_should_fail")) { - err = -EINVAL; - goto cleanup; - } - - /* finally, namespaced CAP_BPF + token -> success */ - map_opts.token_fd = token_fd; - map_fd = bpf_map_create(BPF_MAP_TYPE_STACK, "w_token_w_bpf", 0, 8, 1, &map_opts); - if (!ASSERT_GT(map_fd, 0, "stack_map_w_token_w_cap_bpf")) { - err = -EINVAL; - goto cleanup; - } - -cleanup: - zclose(token_fd); - zclose(map_fd); - return err; -} - -static int userns_btf_load(int mnt_fd) -{ - LIBBPF_OPTS(bpf_btf_load_opts, btf_opts); - int err, token_fd = -1, btf_fd = -1; - const void *raw_btf_data; - struct btf *btf = NULL; - __u32 raw_btf_size; - __u64 old_caps = 0; - - /* create BPF token from BPF FS mount */ - token_fd = bpf_token_create(mnt_fd, NULL); - if (!ASSERT_GT(token_fd, 0, "token_create")) { - err = -EINVAL; - goto cleanup; - } - - /* while inside non-init userns, we need both a BPF token *and* - * CAP_BPF inside current userns to create privileged map; let's test - * that neither BPF token alone nor namespaced CAP_BPF is sufficient - */ - err = drop_priv_caps(&old_caps); - if (!ASSERT_OK(err, "drop_caps")) - goto cleanup; - - /* setup a trivial BTF data to load to the kernel */ - btf = btf__new_empty(); - if (!ASSERT_OK_PTR(btf, "empty_btf")) - goto cleanup; - - ASSERT_GT(btf__add_int(btf, "int", 4, 0), 0, "int_type"); - - raw_btf_data = btf__raw_data(btf, &raw_btf_size); - if (!ASSERT_OK_PTR(raw_btf_data, "raw_btf_data")) - goto cleanup; - - /* no token + no CAP_BPF -> failure */ - btf_opts.token_fd = 0; - btf_fd = bpf_btf_load(raw_btf_data, raw_btf_size, &btf_opts); - if (!ASSERT_LT(btf_fd, 0, "no_token_no_cap_should_fail")) - goto cleanup; - - /* token + no CAP_BPF -> failure */ - btf_opts.token_fd = token_fd; - btf_fd = bpf_btf_load(raw_btf_data, raw_btf_size, &btf_opts); - if (!ASSERT_LT(btf_fd, 0, "token_no_cap_should_fail")) - goto cleanup; - - /* get back effective local CAP_BPF (and CAP_SYS_ADMIN) */ - err = restore_priv_caps(old_caps); - if (!ASSERT_OK(err, "restore_caps")) - goto cleanup; - - /* token + CAP_BPF -> success */ - btf_opts.token_fd = token_fd; - btf_fd = bpf_btf_load(raw_btf_data, raw_btf_size, &btf_opts); - if (!ASSERT_GT(btf_fd, 0, "token_and_cap_success")) - goto cleanup; - - err = 0; -cleanup: - btf__free(btf); - zclose(btf_fd); - zclose(token_fd); - return err; -} - -static int userns_prog_load(int mnt_fd) -{ - LIBBPF_OPTS(bpf_prog_load_opts, prog_opts); - int err, token_fd = -1, prog_fd = -1; - struct bpf_insn insns[] = { - /* bpf_jiffies64() requires CAP_BPF */ - BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_jiffies64), - /* bpf_get_current_task() requires CAP_PERFMON */ - BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_get_current_task), - /* r0 = 0; exit; */ - BPF_MOV64_IMM(BPF_REG_0, 0), - BPF_EXIT_INSN(), - }; - size_t insn_cnt = ARRAY_SIZE(insns); - __u64 old_caps = 0; - - /* create BPF token from BPF FS mount */ - token_fd = bpf_token_create(mnt_fd, NULL); - if (!ASSERT_GT(token_fd, 0, "token_create")) { - err = -EINVAL; - goto cleanup; - } - - /* validate we can successfully load BPF program with token; this - * being XDP program (CAP_NET_ADMIN) using bpf_jiffies64() (CAP_BPF) - * and bpf_get_current_task() (CAP_PERFMON) helpers validates we have - * BPF token wired properly in a bunch of places in the kernel - */ - prog_opts.token_fd = token_fd; - prog_opts.expected_attach_type = BPF_XDP; - prog_fd = bpf_prog_load(BPF_PROG_TYPE_XDP, "token_prog", "GPL", - insns, insn_cnt, &prog_opts); - if (!ASSERT_GT(prog_fd, 0, "prog_fd")) { - err = -EPERM; - goto cleanup; - } - - /* no token + caps -> failure */ - prog_opts.token_fd = 0; - prog_fd = bpf_prog_load(BPF_PROG_TYPE_XDP, "token_prog", "GPL", - insns, insn_cnt, &prog_opts); - if (!ASSERT_EQ(prog_fd, -EPERM, "prog_fd_eperm")) { - err = -EPERM; - goto cleanup; - } - - err = drop_priv_caps(&old_caps); - if (!ASSERT_OK(err, "drop_caps")) - goto cleanup; - - /* no caps + token -> failure */ - prog_opts.token_fd = token_fd; - prog_fd = bpf_prog_load(BPF_PROG_TYPE_XDP, "token_prog", "GPL", - insns, insn_cnt, &prog_opts); - if (!ASSERT_EQ(prog_fd, -EPERM, "prog_fd_eperm")) { - err = -EPERM; - goto cleanup; - } - - /* no caps + no token -> definitely a failure */ - prog_opts.token_fd = 0; - prog_fd = bpf_prog_load(BPF_PROG_TYPE_XDP, "token_prog", "GPL", - insns, insn_cnt, &prog_opts); - if (!ASSERT_EQ(prog_fd, -EPERM, "prog_fd_eperm")) { - err = -EPERM; - goto cleanup; - } - - err = 0; -cleanup: - zclose(prog_fd); - zclose(token_fd); - return err; -} - -static int userns_obj_priv_map(int mnt_fd) -{ - LIBBPF_OPTS(bpf_object_open_opts, opts); - char buf[256]; - struct priv_map *skel; - int err, token_fd; - - skel = priv_map__open_and_load(); - if (!ASSERT_ERR_PTR(skel, "obj_tokenless_load")) { - priv_map__destroy(skel); - return -EINVAL; - } - - /* use bpf_token_path to provide BPF FS path */ - snprintf(buf, sizeof(buf), "/proc/self/fd/%d", mnt_fd); - opts.bpf_token_path = buf; - skel = priv_map__open_opts(&opts); - if (!ASSERT_OK_PTR(skel, "obj_token_path_open")) - return -EINVAL; - - err = priv_map__load(skel); - priv_map__destroy(skel); - if (!ASSERT_OK(err, "obj_token_path_load")) - return -EINVAL; - - /* create token and pass it through bpf_token_fd */ - token_fd = bpf_token_create(mnt_fd, NULL); - if (!ASSERT_GT(token_fd, 0, "create_token")) - return -EINVAL; - - opts.bpf_token_path = NULL; - opts.bpf_token_fd = token_fd; - skel = priv_map__open_opts(&opts); - if (!ASSERT_OK_PTR(skel, "obj_token_fd_open")) - return -EINVAL; - - /* we can close our token FD, bpf_object owns dup()'ed FD now */ - close(token_fd); - - err = priv_map__load(skel); - priv_map__destroy(skel); - if (!ASSERT_OK(err, "obj_token_fd_load")) - return -EINVAL; - - return 0; -} - -static int userns_obj_priv_prog(int mnt_fd) -{ - LIBBPF_OPTS(bpf_object_open_opts, opts); - char buf[256]; - struct priv_prog *skel; - int err; - - skel = priv_prog__open_and_load(); - if (!ASSERT_ERR_PTR(skel, "obj_tokenless_load")) { - priv_prog__destroy(skel); - return -EINVAL; - } - - /* use bpf_token_path to provide BPF FS path */ - snprintf(buf, sizeof(buf), "/proc/self/fd/%d", mnt_fd); - opts.bpf_token_path = buf; - skel = priv_prog__open_opts(&opts); - if (!ASSERT_OK_PTR(skel, "obj_token_path_open")) - return -EINVAL; - - err = priv_prog__load(skel); - priv_prog__destroy(skel); - if (!ASSERT_OK(err, "obj_token_path_load")) - return -EINVAL; - - return 0; -} - -/* this test is called with BPF FS that doesn't delegate BPF_BTF_LOAD command, - * which should cause struct_ops application to fail, as BTF won't be uploaded - * into the kernel, even if STRUCT_OPS programs themselves are allowed - */ -static int validate_struct_ops_load(int mnt_fd, bool expect_success) -{ - LIBBPF_OPTS(bpf_object_open_opts, opts); - char buf[256]; - struct dummy_st_ops_success *skel; - int err; - - snprintf(buf, sizeof(buf), "/proc/self/fd/%d", mnt_fd); - opts.bpf_token_path = buf; - skel = dummy_st_ops_success__open_opts(&opts); - if (!ASSERT_OK_PTR(skel, "obj_token_path_open")) - return -EINVAL; - - err = dummy_st_ops_success__load(skel); - dummy_st_ops_success__destroy(skel); - if (expect_success) { - if (!ASSERT_OK(err, "obj_token_path_load")) - return -EINVAL; - } else /* expect failure */ { - if (!ASSERT_ERR(err, "obj_token_path_load")) - return -EINVAL; - } - - return 0; -} - -static int userns_obj_priv_btf_fail(int mnt_fd) -{ - return validate_struct_ops_load(mnt_fd, false /* should fail */); -} - -static int userns_obj_priv_btf_success(int mnt_fd) -{ - return validate_struct_ops_load(mnt_fd, true /* should succeed */); -} - -#define TOKEN_ENVVAR "LIBBPF_BPF_TOKEN_PATH" -#define TOKEN_BPFFS_CUSTOM "/bpf-token-fs" - -static int userns_obj_priv_implicit_token(int mnt_fd) -{ - LIBBPF_OPTS(bpf_object_open_opts, opts); - struct dummy_st_ops_success *skel; - int err; - - /* before we mount BPF FS with token delegation, struct_ops skeleton - * should fail to load - */ - skel = dummy_st_ops_success__open_and_load(); - if (!ASSERT_ERR_PTR(skel, "obj_tokenless_load")) { - dummy_st_ops_success__destroy(skel); - return -EINVAL; - } - - /* mount custom BPF FS over /sys/fs/bpf so that libbpf can create BPF - * token automatically and implicitly - */ - err = sys_move_mount(mnt_fd, "", AT_FDCWD, "/sys/fs/bpf", MOVE_MOUNT_F_EMPTY_PATH); - if (!ASSERT_OK(err, "move_mount_bpffs")) - return -EINVAL; - - /* disable implicit BPF token creation by setting - * LIBBPF_BPF_TOKEN_PATH envvar to empty value, load should fail - */ - err = setenv(TOKEN_ENVVAR, "", 1 /*overwrite*/); - if (!ASSERT_OK(err, "setenv_token_path")) - return -EINVAL; - skel = dummy_st_ops_success__open_and_load(); - if (!ASSERT_ERR_PTR(skel, "obj_token_envvar_disabled_load")) { - unsetenv(TOKEN_ENVVAR); - dummy_st_ops_success__destroy(skel); - return -EINVAL; - } - unsetenv(TOKEN_ENVVAR); - - /* now the same struct_ops skeleton should succeed thanks to libppf - * creating BPF token from /sys/fs/bpf mount point - */ - skel = dummy_st_ops_success__open_and_load(); - if (!ASSERT_OK_PTR(skel, "obj_implicit_token_load")) - return -EINVAL; - - dummy_st_ops_success__destroy(skel); - - /* now disable implicit token through empty bpf_token_path, should fail */ - opts.bpf_token_path = ""; - skel = dummy_st_ops_success__open_opts(&opts); - if (!ASSERT_OK_PTR(skel, "obj_empty_token_path_open")) - return -EINVAL; - - err = dummy_st_ops_success__load(skel); - dummy_st_ops_success__destroy(skel); - if (!ASSERT_ERR(err, "obj_empty_token_path_load")) - return -EINVAL; - - /* now disable implicit token through negative bpf_token_fd, should fail */ - opts.bpf_token_path = NULL; - opts.bpf_token_fd = -1; - skel = dummy_st_ops_success__open_opts(&opts); - if (!ASSERT_OK_PTR(skel, "obj_neg_token_fd_open")) - return -EINVAL; - - err = dummy_st_ops_success__load(skel); - dummy_st_ops_success__destroy(skel); - if (!ASSERT_ERR(err, "obj_neg_token_fd_load")) - return -EINVAL; - - return 0; -} - -static int userns_obj_priv_implicit_token_envvar(int mnt_fd) -{ - LIBBPF_OPTS(bpf_object_open_opts, opts); - struct dummy_st_ops_success *skel; - int err; - - /* before we mount BPF FS with token delegation, struct_ops skeleton - * should fail to load - */ - skel = dummy_st_ops_success__open_and_load(); - if (!ASSERT_ERR_PTR(skel, "obj_tokenless_load")) { - dummy_st_ops_success__destroy(skel); - return -EINVAL; - } - - /* mount custom BPF FS over custom location, so libbpf can't create - * BPF token implicitly, unless pointed to it through - * LIBBPF_BPF_TOKEN_PATH envvar - */ - rmdir(TOKEN_BPFFS_CUSTOM); - if (!ASSERT_OK(mkdir(TOKEN_BPFFS_CUSTOM, 0777), "mkdir_bpffs_custom")) - goto err_out; - err = sys_move_mount(mnt_fd, "", AT_FDCWD, TOKEN_BPFFS_CUSTOM, MOVE_MOUNT_F_EMPTY_PATH); - if (!ASSERT_OK(err, "move_mount_bpffs")) - goto err_out; - - /* even though we have BPF FS with delegation, it's not at default - * /sys/fs/bpf location, so we still fail to load until envvar is set up - */ - skel = dummy_st_ops_success__open_and_load(); - if (!ASSERT_ERR_PTR(skel, "obj_tokenless_load2")) { - dummy_st_ops_success__destroy(skel); - goto err_out; - } - - err = setenv(TOKEN_ENVVAR, TOKEN_BPFFS_CUSTOM, 1 /*overwrite*/); - if (!ASSERT_OK(err, "setenv_token_path")) - goto err_out; - - /* now the same struct_ops skeleton should succeed thanks to libppf - * creating BPF token from custom mount point - */ - skel = dummy_st_ops_success__open_and_load(); - if (!ASSERT_OK_PTR(skel, "obj_implicit_token_load")) - goto err_out; - - dummy_st_ops_success__destroy(skel); - - /* now disable implicit token through empty bpf_token_path, envvar - * will be ignored, should fail - */ - opts.bpf_token_path = ""; - skel = dummy_st_ops_success__open_opts(&opts); - if (!ASSERT_OK_PTR(skel, "obj_empty_token_path_open")) - goto err_out; - - err = dummy_st_ops_success__load(skel); - dummy_st_ops_success__destroy(skel); - if (!ASSERT_ERR(err, "obj_empty_token_path_load")) - goto err_out; - - /* now disable implicit token through negative bpf_token_fd, envvar - * will be ignored, should fail - */ - opts.bpf_token_path = NULL; - opts.bpf_token_fd = -1; - skel = dummy_st_ops_success__open_opts(&opts); - if (!ASSERT_OK_PTR(skel, "obj_neg_token_fd_open")) - goto err_out; - - err = dummy_st_ops_success__load(skel); - dummy_st_ops_success__destroy(skel); - if (!ASSERT_ERR(err, "obj_neg_token_fd_load")) - goto err_out; - - rmdir(TOKEN_BPFFS_CUSTOM); - unsetenv(TOKEN_ENVVAR); - return 0; -err_out: - rmdir(TOKEN_BPFFS_CUSTOM); - unsetenv(TOKEN_ENVVAR); - return -EINVAL; -} - -#define bit(n) (1ULL << (n)) - -void test_token(void) -{ - if (test__start_subtest("map_token")) { - struct bpffs_opts opts = { - .cmds_str = "map_create", - .maps_str = "stack", - }; - - subtest_userns(&opts, userns_map_create); - } - if (test__start_subtest("btf_token")) { - struct bpffs_opts opts = { - .cmds = 1ULL << BPF_BTF_LOAD, - }; - - subtest_userns(&opts, userns_btf_load); - } - if (test__start_subtest("prog_token")) { - struct bpffs_opts opts = { - .cmds_str = "PROG_LOAD", - .progs_str = "XDP", - .attachs_str = "xdp", - }; - - subtest_userns(&opts, userns_prog_load); - } - if (test__start_subtest("obj_priv_map")) { - struct bpffs_opts opts = { - .cmds = bit(BPF_MAP_CREATE), - .maps = bit(BPF_MAP_TYPE_QUEUE), - }; - - subtest_userns(&opts, userns_obj_priv_map); - } - if (test__start_subtest("obj_priv_prog")) { - struct bpffs_opts opts = { - .cmds = bit(BPF_PROG_LOAD), - .progs = bit(BPF_PROG_TYPE_KPROBE), - .attachs = ~0ULL, - }; - - subtest_userns(&opts, userns_obj_priv_prog); - } - if (test__start_subtest("obj_priv_btf_fail")) { - struct bpffs_opts opts = { - /* disallow BTF loading */ - .cmds = bit(BPF_MAP_CREATE) | bit(BPF_PROG_LOAD), - .maps = bit(BPF_MAP_TYPE_STRUCT_OPS), - .progs = bit(BPF_PROG_TYPE_STRUCT_OPS), - .attachs = ~0ULL, - }; - - subtest_userns(&opts, userns_obj_priv_btf_fail); - } - if (test__start_subtest("obj_priv_btf_success")) { - struct bpffs_opts opts = { - /* allow BTF loading */ - .cmds = bit(BPF_BTF_LOAD) | bit(BPF_MAP_CREATE) | bit(BPF_PROG_LOAD), - .maps = bit(BPF_MAP_TYPE_STRUCT_OPS), - .progs = bit(BPF_PROG_TYPE_STRUCT_OPS), - .attachs = ~0ULL, - }; - - subtest_userns(&opts, userns_obj_priv_btf_success); - } - if (test__start_subtest("obj_priv_implicit_token")) { - struct bpffs_opts opts = { - /* allow BTF loading */ - .cmds = bit(BPF_BTF_LOAD) | bit(BPF_MAP_CREATE) | bit(BPF_PROG_LOAD), - .maps = bit(BPF_MAP_TYPE_STRUCT_OPS), - .progs = bit(BPF_PROG_TYPE_STRUCT_OPS), - .attachs = ~0ULL, - }; - - subtest_userns(&opts, userns_obj_priv_implicit_token); - } - if (test__start_subtest("obj_priv_implicit_token_envvar")) { - struct bpffs_opts opts = { - /* allow BTF loading */ - .cmds = bit(BPF_BTF_LOAD) | bit(BPF_MAP_CREATE) | bit(BPF_PROG_LOAD), - .maps = bit(BPF_MAP_TYPE_STRUCT_OPS), - .progs = bit(BPF_PROG_TYPE_STRUCT_OPS), - .attachs = ~0ULL, - }; - - subtest_userns(&opts, userns_obj_priv_implicit_token_envvar); - } -} diff --git a/tools/testing/selftests/bpf/progs/priv_map.c b/tools/testing/selftests/bpf/progs/priv_map.c deleted file mode 100644 index 9085be50f03b..000000000000 --- a/tools/testing/selftests/bpf/progs/priv_map.c +++ /dev/null @@ -1,13 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -/* Copyright (c) 2023 Meta Platforms, Inc. and affiliates. */ - -#include "vmlinux.h" -#include - -char _license[] SEC("license") = "GPL"; - -struct { - __uint(type, BPF_MAP_TYPE_QUEUE); - __uint(max_entries, 1); - __type(value, __u32); -} priv_map SEC(".maps"); diff --git a/tools/testing/selftests/bpf/progs/priv_prog.c b/tools/testing/selftests/bpf/progs/priv_prog.c deleted file mode 100644 index 3c7b2b618c8a..000000000000 --- a/tools/testing/selftests/bpf/progs/priv_prog.c +++ /dev/null @@ -1,13 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -/* Copyright (c) 2023 Meta Platforms, Inc. and affiliates. */ - -#include "vmlinux.h" -#include - -char _license[] SEC("license") = "GPL"; - -SEC("kprobe") -int kprobe_prog(void *ctx) -{ - return 1; -} -- cgit