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-rw-r--r--kernel/bpf/syscall.c675
1 files changed, 444 insertions, 231 deletions
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index b999e7ff2583..c859bc46d06c 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -4,6 +4,7 @@
#include <linux/bpf.h>
#include <linux/bpf_trace.h>
#include <linux/bpf_lirc.h>
+#include <linux/bpf_verifier.h>
#include <linux/btf.h>
#include <linux/syscalls.h>
#include <linux/slab.h>
@@ -16,7 +17,6 @@
#include <linux/fs.h>
#include <linux/license.h>
#include <linux/filter.h>
-#include <linux/version.h>
#include <linux/kernel.h>
#include <linux/idr.h>
#include <linux/cred.h>
@@ -29,6 +29,8 @@
#include <linux/bpf_lsm.h>
#include <linux/poll.h>
#include <linux/bpf-netns.h>
+#include <linux/rcupdate_trace.h>
+#include <linux/memcontrol.h>
#define IS_FD_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PERF_EVENT_ARRAY || \
(map)->map_type == BPF_MAP_TYPE_CGROUP_ARRAY || \
@@ -90,6 +92,7 @@ int bpf_check_uarg_tail_zero(void __user *uaddr,
}
const struct bpf_map_ops bpf_map_offload_ops = {
+ .map_meta_equal = bpf_map_meta_equal,
.map_alloc = bpf_map_offload_map_alloc,
.map_free = bpf_map_offload_map_free,
.map_check_btf = map_check_no_btf,
@@ -124,7 +127,7 @@ static struct bpf_map *find_and_alloc_map(union bpf_attr *attr)
return map;
}
-static u32 bpf_map_value_size(struct bpf_map *map)
+static u32 bpf_map_value_size(const struct bpf_map *map)
{
if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH ||
@@ -157,10 +160,11 @@ static int bpf_map_update_value(struct bpf_map *map, struct fd f, void *key,
if (bpf_map_is_dev_bound(map)) {
return bpf_map_offload_update_elem(map, key, value, flags);
} else if (map->map_type == BPF_MAP_TYPE_CPUMAP ||
- map->map_type == BPF_MAP_TYPE_SOCKHASH ||
- map->map_type == BPF_MAP_TYPE_SOCKMAP ||
map->map_type == BPF_MAP_TYPE_STRUCT_OPS) {
return map->ops->map_update_elem(map, key, value, flags);
+ } else if (map->map_type == BPF_MAP_TYPE_SOCKHASH ||
+ map->map_type == BPF_MAP_TYPE_SOCKMAP) {
+ return sock_map_update_elem_sys(map, key, value, flags);
} else if (IS_FD_PROG_ARRAY(map)) {
return bpf_fd_array_map_update_elem(map, f.file, key, value,
flags);
@@ -263,6 +267,10 @@ static int bpf_map_copy_value(struct bpf_map *map, void *key, void *value,
return err;
}
+/* Please, do not use this function outside from the map creation path
+ * (e.g. in map update path) without taking care of setting the active
+ * memory cgroup (see at bpf_map_kmalloc_node() for example).
+ */
static void *__bpf_map_area_alloc(u64 size, int numa_node, bool mmapable)
{
/* We really just want to fail instead of triggering OOM killer
@@ -275,7 +283,7 @@ static void *__bpf_map_area_alloc(u64 size, int numa_node, bool mmapable)
* __GFP_RETRY_MAYFAIL to avoid such situations.
*/
- const gfp_t gfp = __GFP_NOWARN | __GFP_ZERO;
+ const gfp_t gfp = __GFP_NOWARN | __GFP_ZERO | __GFP_ACCOUNT;
unsigned int flags = 0;
unsigned long align = 1;
void *area;
@@ -337,77 +345,6 @@ void bpf_map_init_from_attr(struct bpf_map *map, union bpf_attr *attr)
map->numa_node = bpf_map_attr_numa_node(attr);
}
-static int bpf_charge_memlock(struct user_struct *user, u32 pages)
-{
- unsigned long memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
-
- if (atomic_long_add_return(pages, &user->locked_vm) > memlock_limit) {
- atomic_long_sub(pages, &user->locked_vm);
- return -EPERM;
- }
- return 0;
-}
-
-static void bpf_uncharge_memlock(struct user_struct *user, u32 pages)
-{
- if (user)
- atomic_long_sub(pages, &user->locked_vm);
-}
-
-int bpf_map_charge_init(struct bpf_map_memory *mem, u64 size)
-{
- u32 pages = round_up(size, PAGE_SIZE) >> PAGE_SHIFT;
- struct user_struct *user;
- int ret;
-
- if (size >= U32_MAX - PAGE_SIZE)
- return -E2BIG;
-
- user = get_current_user();
- ret = bpf_charge_memlock(user, pages);
- if (ret) {
- free_uid(user);
- return ret;
- }
-
- mem->pages = pages;
- mem->user = user;
-
- return 0;
-}
-
-void bpf_map_charge_finish(struct bpf_map_memory *mem)
-{
- bpf_uncharge_memlock(mem->user, mem->pages);
- free_uid(mem->user);
-}
-
-void bpf_map_charge_move(struct bpf_map_memory *dst,
- struct bpf_map_memory *src)
-{
- *dst = *src;
-
- /* Make sure src will not be used for the redundant uncharging. */
- memset(src, 0, sizeof(struct bpf_map_memory));
-}
-
-int bpf_map_charge_memlock(struct bpf_map *map, u32 pages)
-{
- int ret;
-
- ret = bpf_charge_memlock(map->memory.user, pages);
- if (ret)
- return ret;
- map->memory.pages += pages;
- return ret;
-}
-
-void bpf_map_uncharge_memlock(struct bpf_map *map, u32 pages)
-{
- bpf_uncharge_memlock(map->memory.user, pages);
- map->memory.pages -= pages;
-}
-
static int bpf_map_alloc_id(struct bpf_map *map)
{
int id;
@@ -452,17 +389,74 @@ void bpf_map_free_id(struct bpf_map *map, bool do_idr_lock)
__release(&map_idr_lock);
}
+#ifdef CONFIG_MEMCG_KMEM
+static void bpf_map_save_memcg(struct bpf_map *map)
+{
+ map->memcg = get_mem_cgroup_from_mm(current->mm);
+}
+
+static void bpf_map_release_memcg(struct bpf_map *map)
+{
+ mem_cgroup_put(map->memcg);
+}
+
+void *bpf_map_kmalloc_node(const struct bpf_map *map, size_t size, gfp_t flags,
+ int node)
+{
+ struct mem_cgroup *old_memcg;
+ void *ptr;
+
+ old_memcg = set_active_memcg(map->memcg);
+ ptr = kmalloc_node(size, flags | __GFP_ACCOUNT, node);
+ set_active_memcg(old_memcg);
+
+ return ptr;
+}
+
+void *bpf_map_kzalloc(const struct bpf_map *map, size_t size, gfp_t flags)
+{
+ struct mem_cgroup *old_memcg;
+ void *ptr;
+
+ old_memcg = set_active_memcg(map->memcg);
+ ptr = kzalloc(size, flags | __GFP_ACCOUNT);
+ set_active_memcg(old_memcg);
+
+ return ptr;
+}
+
+void __percpu *bpf_map_alloc_percpu(const struct bpf_map *map, size_t size,
+ size_t align, gfp_t flags)
+{
+ struct mem_cgroup *old_memcg;
+ void __percpu *ptr;
+
+ old_memcg = set_active_memcg(map->memcg);
+ ptr = __alloc_percpu_gfp(size, align, flags | __GFP_ACCOUNT);
+ set_active_memcg(old_memcg);
+
+ return ptr;
+}
+
+#else
+static void bpf_map_save_memcg(struct bpf_map *map)
+{
+}
+
+static void bpf_map_release_memcg(struct bpf_map *map)
+{
+}
+#endif
+
/* called from workqueue */
static void bpf_map_free_deferred(struct work_struct *work)
{
struct bpf_map *map = container_of(work, struct bpf_map, work);
- struct bpf_map_memory mem;
- bpf_map_charge_move(&mem, &map->memory);
security_bpf_map_free(map);
+ bpf_map_release_memcg(map);
/* implementation dependent freeing */
map->ops->map_free(map);
- bpf_map_charge_finish(&mem);
}
static void bpf_map_put_uref(struct bpf_map *map)
@@ -523,6 +517,19 @@ static fmode_t map_get_sys_perms(struct bpf_map *map, struct fd f)
}
#ifdef CONFIG_PROC_FS
+/* Provides an approximation of the map's memory footprint.
+ * Used only to provide a backward compatibility and display
+ * a reasonable "memlock" info.
+ */
+static unsigned long bpf_map_memory_footprint(const struct bpf_map *map)
+{
+ unsigned long size;
+
+ size = round_up(map->key_size + bpf_map_value_size(map), 8);
+
+ return round_up(map->max_entries * size, PAGE_SIZE);
+}
+
static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp)
{
const struct bpf_map *map = filp->private_data;
@@ -541,7 +548,7 @@ static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp)
"value_size:\t%u\n"
"max_entries:\t%u\n"
"map_flags:\t%#x\n"
- "memlock:\t%llu\n"
+ "memlock:\t%lu\n"
"map_id:\t%u\n"
"frozen:\t%u\n",
map->map_type,
@@ -549,7 +556,7 @@ static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp)
map->value_size,
map->max_entries,
map->map_flags,
- map->memory.pages * 1ULL << PAGE_SHIFT,
+ bpf_map_memory_footprint(map),
map->id,
READ_ONCE(map->frozen));
if (type) {
@@ -768,7 +775,9 @@ static int map_check_btf(struct bpf_map *map, const struct btf *btf,
if (map->map_type != BPF_MAP_TYPE_HASH &&
map->map_type != BPF_MAP_TYPE_ARRAY &&
map->map_type != BPF_MAP_TYPE_CGROUP_STORAGE &&
- map->map_type != BPF_MAP_TYPE_SK_STORAGE)
+ map->map_type != BPF_MAP_TYPE_SK_STORAGE &&
+ map->map_type != BPF_MAP_TYPE_INODE_STORAGE &&
+ map->map_type != BPF_MAP_TYPE_TASK_STORAGE)
return -ENOTSUPP;
if (map->spin_lock_off + sizeof(struct bpf_spin_lock) >
map->value_size) {
@@ -790,7 +799,6 @@ static int map_check_btf(struct bpf_map *map, const struct btf *btf,
static int map_create(union bpf_attr *attr)
{
int numa_node = bpf_map_attr_numa_node(attr);
- struct bpf_map_memory mem;
struct bpf_map *map;
int f_flags;
int err;
@@ -869,6 +877,8 @@ static int map_create(union bpf_attr *attr)
if (err)
goto free_map_sec;
+ bpf_map_save_memcg(map);
+
err = bpf_map_new_fd(map, f_flags);
if (err < 0) {
/* failed to allocate fd.
@@ -887,9 +897,7 @@ free_map_sec:
security_bpf_map_free(map);
free_map:
btf_put(map->btf);
- bpf_map_charge_move(&mem, &map->memory);
map->ops->map_free(map);
- bpf_map_charge_finish(&mem);
return err;
}
@@ -1623,51 +1631,6 @@ static void bpf_audit_prog(const struct bpf_prog *prog, unsigned int op)
audit_log_end(ab);
}
-int __bpf_prog_charge(struct user_struct *user, u32 pages)
-{
- unsigned long memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
- unsigned long user_bufs;
-
- if (user) {
- user_bufs = atomic_long_add_return(pages, &user->locked_vm);
- if (user_bufs > memlock_limit) {
- atomic_long_sub(pages, &user->locked_vm);
- return -EPERM;
- }
- }
-
- return 0;
-}
-
-void __bpf_prog_uncharge(struct user_struct *user, u32 pages)
-{
- if (user)
- atomic_long_sub(pages, &user->locked_vm);
-}
-
-static int bpf_prog_charge_memlock(struct bpf_prog *prog)
-{
- struct user_struct *user = get_current_user();
- int ret;
-
- ret = __bpf_prog_charge(user, prog->pages);
- if (ret) {
- free_uid(user);
- return ret;
- }
-
- prog->aux->user = user;
- return 0;
-}
-
-static void bpf_prog_uncharge_memlock(struct bpf_prog *prog)
-{
- struct user_struct *user = prog->aux->user;
-
- __bpf_prog_uncharge(user, prog->pages);
- free_uid(user);
-}
-
static int bpf_prog_alloc_id(struct bpf_prog *prog)
{
int id;
@@ -1717,7 +1680,7 @@ static void __bpf_prog_put_rcu(struct rcu_head *rcu)
kvfree(aux->func_info);
kfree(aux->func_info_aux);
- bpf_prog_uncharge_memlock(aux->prog);
+ free_uid(aux->user);
security_bpf_prog_free(aux);
bpf_prog_free(aux->prog);
}
@@ -1727,11 +1690,17 @@ static void __bpf_prog_put_noref(struct bpf_prog *prog, bool deferred)
bpf_prog_kallsyms_del_all(prog);
btf_put(prog->aux->btf);
bpf_prog_free_linfo(prog);
+ if (prog->aux->attach_btf)
+ btf_put(prog->aux->attach_btf);
- if (deferred)
- call_rcu(&prog->aux->rcu, __bpf_prog_put_rcu);
- else
+ if (deferred) {
+ if (prog->aux->sleepable)
+ call_rcu_tasks_trace(&prog->aux->rcu, __bpf_prog_put_rcu);
+ else
+ call_rcu(&prog->aux->rcu, __bpf_prog_put_rcu);
+ } else {
__bpf_prog_put_rcu(&prog->aux->rcu);
+ }
}
static void __bpf_prog_put(struct bpf_prog *prog, bool do_idr_lock)
@@ -1762,25 +1731,28 @@ static int bpf_prog_release(struct inode *inode, struct file *filp)
static void bpf_prog_get_stats(const struct bpf_prog *prog,
struct bpf_prog_stats *stats)
{
- u64 nsecs = 0, cnt = 0;
+ u64 nsecs = 0, cnt = 0, misses = 0;
int cpu;
for_each_possible_cpu(cpu) {
const struct bpf_prog_stats *st;
unsigned int start;
- u64 tnsecs, tcnt;
+ u64 tnsecs, tcnt, tmisses;
- st = per_cpu_ptr(prog->aux->stats, cpu);
+ st = per_cpu_ptr(prog->stats, cpu);
do {
start = u64_stats_fetch_begin_irq(&st->syncp);
tnsecs = st->nsecs;
tcnt = st->cnt;
+ tmisses = st->misses;
} while (u64_stats_fetch_retry_irq(&st->syncp, start));
nsecs += tnsecs;
cnt += tcnt;
+ misses += tmisses;
}
stats->nsecs = nsecs;
stats->cnt = cnt;
+ stats->misses = misses;
}
#ifdef CONFIG_PROC_FS
@@ -1799,14 +1771,16 @@ static void bpf_prog_show_fdinfo(struct seq_file *m, struct file *filp)
"memlock:\t%llu\n"
"prog_id:\t%u\n"
"run_time_ns:\t%llu\n"
- "run_cnt:\t%llu\n",
+ "run_cnt:\t%llu\n"
+ "recursion_misses:\t%llu\n",
prog->type,
prog->jited,
prog_tag,
prog->pages * 1ULL << PAGE_SHIFT,
prog->aux->id,
stats.nsecs,
- stats.cnt);
+ stats.cnt,
+ stats.misses);
}
#endif
@@ -1956,12 +1930,16 @@ static void bpf_prog_load_fixup_attach_type(union bpf_attr *attr)
static int
bpf_prog_load_check_attach(enum bpf_prog_type prog_type,
enum bpf_attach_type expected_attach_type,
- u32 btf_id, u32 prog_fd)
+ struct btf *attach_btf, u32 btf_id,
+ struct bpf_prog *dst_prog)
{
if (btf_id) {
if (btf_id > BTF_MAX_TYPE)
return -EINVAL;
+ if (!attach_btf && !dst_prog)
+ return -EINVAL;
+
switch (prog_type) {
case BPF_PROG_TYPE_TRACING:
case BPF_PROG_TYPE_LSM:
@@ -1973,7 +1951,10 @@ bpf_prog_load_check_attach(enum bpf_prog_type prog_type,
}
}
- if (prog_fd && prog_type != BPF_PROG_TYPE_TRACING &&
+ if (attach_btf && (!btf_id || dst_prog))
+ return -EINVAL;
+
+ if (dst_prog && prog_type != BPF_PROG_TYPE_TRACING &&
prog_type != BPF_PROG_TYPE_EXT)
return -EINVAL;
@@ -2090,7 +2071,8 @@ static bool is_perfmon_prog_type(enum bpf_prog_type prog_type)
static int bpf_prog_load(union bpf_attr *attr, union bpf_attr __user *uattr)
{
enum bpf_prog_type type = attr->prog_type;
- struct bpf_prog *prog;
+ struct bpf_prog *prog, *dst_prog = NULL;
+ struct btf *attach_btf = NULL;
int err;
char license[128];
bool is_gpl;
@@ -2101,6 +2083,7 @@ static int bpf_prog_load(union bpf_attr *attr, union bpf_attr __user *uattr)
if (attr->prog_flags & ~(BPF_F_STRICT_ALIGNMENT |
BPF_F_ANY_ALIGNMENT |
BPF_F_TEST_STATE_FREQ |
+ BPF_F_SLEEPABLE |
BPF_F_TEST_RND_HI32))
return -EINVAL;
@@ -2131,46 +2114,73 @@ static int bpf_prog_load(union bpf_attr *attr, union bpf_attr __user *uattr)
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
+ */
+ if (attr->attach_prog_fd) {
+ dst_prog = bpf_prog_get(attr->attach_prog_fd);
+ if (IS_ERR(dst_prog)) {
+ dst_prog = NULL;
+ attach_btf = btf_get_by_fd(attr->attach_btf_obj_fd);
+ 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);
+ 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))
+ 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,
- attr->attach_btf_id,
- attr->attach_prog_fd))
+ attach_btf, attr->attach_btf_id,
+ dst_prog)) {
+ if (dst_prog)
+ bpf_prog_put(dst_prog);
+ if (attach_btf)
+ btf_put(attach_btf);
return -EINVAL;
+ }
/* plain bpf_prog allocation */
prog = bpf_prog_alloc(bpf_prog_size(attr->insn_cnt), GFP_USER);
- if (!prog)
+ if (!prog) {
+ if (dst_prog)
+ bpf_prog_put(dst_prog);
+ if (attach_btf)
+ btf_put(attach_btf);
return -ENOMEM;
+ }
prog->expected_attach_type = attr->expected_attach_type;
+ prog->aux->attach_btf = attach_btf;
prog->aux->attach_btf_id = attr->attach_btf_id;
- if (attr->attach_prog_fd) {
- struct bpf_prog *tgt_prog;
-
- tgt_prog = bpf_prog_get(attr->attach_prog_fd);
- if (IS_ERR(tgt_prog)) {
- err = PTR_ERR(tgt_prog);
- goto free_prog_nouncharge;
- }
- prog->aux->linked_prog = tgt_prog;
- }
-
+ prog->aux->dst_prog = dst_prog;
prog->aux->offload_requested = !!attr->prog_ifindex;
+ prog->aux->sleepable = attr->prog_flags & BPF_F_SLEEPABLE;
err = security_bpf_prog_alloc(prog->aux);
if (err)
- goto free_prog_nouncharge;
-
- err = bpf_prog_charge_memlock(prog);
- if (err)
- goto free_prog_sec;
+ goto free_prog;
+ prog->aux->user = get_current_user();
prog->len = attr->insn_cnt;
err = -EFAULT;
if (copy_from_user(prog->insns, u64_to_user_ptr(attr->insns),
bpf_prog_insn_size(prog)) != 0)
- goto free_prog;
+ goto free_prog_sec;
prog->orig_prog = NULL;
prog->jited = 0;
@@ -2181,19 +2191,19 @@ static int bpf_prog_load(union bpf_attr *attr, union bpf_attr __user *uattr)
if (bpf_prog_is_dev_bound(prog->aux)) {
err = bpf_prog_offload_init(prog, attr);
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;
+ goto free_prog_sec;
/* run eBPF verifier */
err = bpf_check(&prog, attr, uattr);
@@ -2238,11 +2248,12 @@ free_used_maps:
*/
__bpf_prog_put_noref(prog, prog->aux->func_cnt);
return err;
-free_prog:
- bpf_prog_uncharge_memlock(prog);
free_prog_sec:
+ free_uid(prog->aux->user);
security_bpf_prog_free(prog->aux);
-free_prog_nouncharge:
+free_prog:
+ if (prog->aux->attach_btf)
+ btf_put(prog->aux->attach_btf);
bpf_prog_free(prog);
return err;
}
@@ -2488,11 +2499,23 @@ struct bpf_link *bpf_link_get_from_fd(u32 ufd)
struct bpf_tracing_link {
struct bpf_link link;
enum bpf_attach_type attach_type;
+ struct bpf_trampoline *trampoline;
+ struct bpf_prog *tgt_prog;
};
static void bpf_tracing_link_release(struct bpf_link *link)
{
- WARN_ON_ONCE(bpf_trampoline_unlink_prog(link->prog));
+ struct bpf_tracing_link *tr_link =
+ container_of(link, struct bpf_tracing_link, link);
+
+ WARN_ON_ONCE(bpf_trampoline_unlink_prog(link->prog,
+ tr_link->trampoline));
+
+ bpf_trampoline_put(tr_link->trampoline);
+
+ /* tgt_prog is NULL if target is a kernel function */
+ if (tr_link->tgt_prog)
+ bpf_prog_put(tr_link->tgt_prog);
}
static void bpf_tracing_link_dealloc(struct bpf_link *link)
@@ -2532,10 +2555,15 @@ static const struct bpf_link_ops bpf_tracing_link_lops = {
.fill_link_info = bpf_tracing_link_fill_link_info,
};
-static int bpf_tracing_prog_attach(struct bpf_prog *prog)
+static int bpf_tracing_prog_attach(struct bpf_prog *prog,
+ int tgt_prog_fd,
+ u32 btf_id)
{
struct bpf_link_primer link_primer;
+ struct bpf_prog *tgt_prog = NULL;
+ struct bpf_trampoline *tr = NULL;
struct bpf_tracing_link *link;
+ u64 key = 0;
int err;
switch (prog->type) {
@@ -2564,6 +2592,28 @@ static int bpf_tracing_prog_attach(struct bpf_prog *prog)
goto out_put_prog;
}
+ if (!!tgt_prog_fd != !!btf_id) {
+ err = -EINVAL;
+ goto out_put_prog;
+ }
+
+ if (tgt_prog_fd) {
+ /* For now we only allow new targets for BPF_PROG_TYPE_EXT */
+ if (prog->type != BPF_PROG_TYPE_EXT) {
+ err = -EINVAL;
+ goto out_put_prog;
+ }
+
+ tgt_prog = bpf_prog_get(tgt_prog_fd);
+ if (IS_ERR(tgt_prog)) {
+ err = PTR_ERR(tgt_prog);
+ tgt_prog = NULL;
+ goto out_put_prog;
+ }
+
+ key = bpf_trampoline_compute_key(tgt_prog, NULL, btf_id);
+ }
+
link = kzalloc(sizeof(*link), GFP_USER);
if (!link) {
err = -ENOMEM;
@@ -2573,21 +2623,100 @@ static int bpf_tracing_prog_attach(struct bpf_prog *prog)
&bpf_tracing_link_lops, prog);
link->attach_type = prog->expected_attach_type;
- err = bpf_link_prime(&link->link, &link_primer);
- if (err) {
- kfree(link);
- goto out_put_prog;
+ mutex_lock(&prog->aux->dst_mutex);
+
+ /* There are a few possible cases here:
+ *
+ * - if prog->aux->dst_trampoline is set, the program was just loaded
+ * and not yet attached to anything, so we can use the values stored
+ * in prog->aux
+ *
+ * - if prog->aux->dst_trampoline is NULL, the program has already been
+ * attached to a target and its initial target was cleared (below)
+ *
+ * - if tgt_prog != NULL, the caller specified tgt_prog_fd +
+ * target_btf_id using the link_create API.
+ *
+ * - if tgt_prog == NULL when this function was called using the old
+ * raw_tracepoint_open API, and we need a target from prog->aux
+ *
+ * The combination of no saved target in prog->aux, and no target
+ * specified on load is illegal, and we reject that here.
+ */
+ if (!prog->aux->dst_trampoline && !tgt_prog) {
+ err = -ENOENT;
+ goto out_unlock;
+ }
+
+ if (!prog->aux->dst_trampoline ||
+ (key && key != prog->aux->dst_trampoline->key)) {
+ /* If there is no saved target, or the specified target is
+ * different from the destination specified at load time, we
+ * need a new trampoline and a check for compatibility
+ */
+ struct bpf_attach_target_info tgt_info = {};
+
+ err = bpf_check_attach_target(NULL, prog, tgt_prog, btf_id,
+ &tgt_info);
+ if (err)
+ goto out_unlock;
+
+ tr = bpf_trampoline_get(key, &tgt_info);
+ if (!tr) {
+ err = -ENOMEM;
+ goto out_unlock;
+ }
+ } else {
+ /* The caller didn't specify a target, or the target was the
+ * same as the destination supplied during program load. This
+ * means we can reuse the trampoline and reference from program
+ * load time, and there is no need to allocate a new one. This
+ * can only happen once for any program, as the saved values in
+ * prog->aux are cleared below.
+ */
+ tr = prog->aux->dst_trampoline;
+ tgt_prog = prog->aux->dst_prog;
}
- err = bpf_trampoline_link_prog(prog);
+ err = bpf_link_prime(&link->link, &link_primer);
+ if (err)
+ goto out_unlock;
+
+ err = bpf_trampoline_link_prog(prog, tr);
if (err) {
bpf_link_cleanup(&link_primer);
- goto out_put_prog;
+ link = NULL;
+ goto out_unlock;
}
+ link->tgt_prog = tgt_prog;
+ link->trampoline = tr;
+
+ /* Always clear the trampoline and target prog from prog->aux to make
+ * sure the original attach destination is not kept alive after a
+ * program is (re-)attached to another target.
+ */
+ if (prog->aux->dst_prog &&
+ (tgt_prog_fd || tr != prog->aux->dst_trampoline))
+ /* got extra prog ref from syscall, or attaching to different prog */
+ bpf_prog_put(prog->aux->dst_prog);
+ if (prog->aux->dst_trampoline && tr != prog->aux->dst_trampoline)
+ /* we allocated a new trampoline, so free the old one */
+ bpf_trampoline_put(prog->aux->dst_trampoline);
+
+ prog->aux->dst_prog = NULL;
+ prog->aux->dst_trampoline = NULL;
+ mutex_unlock(&prog->aux->dst_mutex);
+
return bpf_link_settle(&link_primer);
+out_unlock:
+ if (tr && tr != prog->aux->dst_trampoline)
+ bpf_trampoline_put(tr);
+ mutex_unlock(&prog->aux->dst_mutex);
+ kfree(link);
out_put_prog:
- bpf_prog_put(prog);
+ if (tgt_prog_fd && tgt_prog)
+ bpf_prog_put(tgt_prog);
return err;
}
@@ -2700,7 +2829,10 @@ static int bpf_raw_tracepoint_open(const union bpf_attr *attr)
tp_name = prog->aux->attach_func_name;
break;
}
- return bpf_tracing_prog_attach(prog);
+ err = bpf_tracing_prog_attach(prog, 0, 0);
+ if (err >= 0)
+ return err;
+ goto out_put_prog;
case BPF_PROG_TYPE_RAW_TRACEPOINT:
case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE:
if (strncpy_from_user(buf,
@@ -2783,7 +2915,6 @@ attach_type_to_prog_type(enum bpf_attach_type attach_type)
case BPF_CGROUP_INET_INGRESS:
case BPF_CGROUP_INET_EGRESS:
return BPF_PROG_TYPE_CGROUP_SKB;
- break;
case BPF_CGROUP_INET_SOCK_CREATE:
case BPF_CGROUP_INET_SOCK_RELEASE:
case BPF_CGROUP_INET4_POST_BIND:
@@ -2969,7 +3100,7 @@ static int bpf_prog_query(const union bpf_attr *attr,
}
}
-#define BPF_PROG_TEST_RUN_LAST_FIELD test.ctx_out
+#define BPF_PROG_TEST_RUN_LAST_FIELD test.cpu
static int bpf_prog_test_run(const union bpf_attr *attr,
union bpf_attr __user *uattr)
@@ -3152,21 +3283,25 @@ static const struct bpf_map *bpf_map_from_imm(const struct bpf_prog *prog,
const struct bpf_map *map;
int i;
+ mutex_lock(&prog->aux->used_maps_mutex);
for (i = 0, *off = 0; i < prog->aux->used_map_cnt; i++) {
map = prog->aux->used_maps[i];
if (map == (void *)addr) {
*type = BPF_PSEUDO_MAP_FD;
- return map;
+ goto out;
}
if (!map->ops->map_direct_value_meta)
continue;
if (!map->ops->map_direct_value_meta(map, addr, off)) {
*type = BPF_PSEUDO_MAP_VALUE;
- return map;
+ goto out;
}
}
+ map = NULL;
- return NULL;
+out:
+ mutex_unlock(&prog->aux->used_maps_mutex);
+ return map;
}
static struct bpf_insn *bpf_insn_prepare_dump(const struct bpf_prog *prog,
@@ -3284,6 +3419,7 @@ static int bpf_prog_get_info_by_fd(struct file *file,
memcpy(info.tag, prog->tag, sizeof(prog->tag));
memcpy(info.name, prog->aux->name, sizeof(prog->aux->name));
+ mutex_lock(&prog->aux->used_maps_mutex);
ulen = info.nr_map_ids;
info.nr_map_ids = prog->aux->used_map_cnt;
ulen = min_t(u32, info.nr_map_ids, ulen);
@@ -3293,9 +3429,12 @@ static int bpf_prog_get_info_by_fd(struct file *file,
for (i = 0; i < ulen; i++)
if (put_user(prog->aux->used_maps[i]->id,
- &user_map_ids[i]))
+ &user_map_ids[i])) {
+ mutex_unlock(&prog->aux->used_maps_mutex);
return -EFAULT;
+ }
}
+ mutex_unlock(&prog->aux->used_maps_mutex);
err = set_info_rec_size(&info);
if (err)
@@ -3304,6 +3443,7 @@ static int bpf_prog_get_info_by_fd(struct file *file,
bpf_prog_get_stats(prog, &stats);
info.run_time_ns = stats.nsecs;
info.run_cnt = stats.cnt;
+ info.recursion_misses = stats.misses;
if (!bpf_capable()) {
info.jited_prog_len = 0;
@@ -3451,7 +3591,7 @@ static int bpf_prog_get_info_by_fd(struct file *file,
}
if (prog->aux->btf)
- info.btf_id = btf_id(prog->aux->btf);
+ info.btf_id = btf_obj_id(prog->aux->btf);
ulen = info.nr_func_info;
info.nr_func_info = prog->aux->func_info_cnt;
@@ -3554,7 +3694,7 @@ static int bpf_map_get_info_by_fd(struct file *file,
memcpy(info.name, map->name, sizeof(map->name));
if (map->btf) {
- info.btf_id = btf_id(map->btf);
+ info.btf_id = btf_obj_id(map->btf);
info.btf_key_type_id = map->btf_key_type_id;
info.btf_value_type_id = map->btf_value_type_id;
}
@@ -3741,7 +3881,6 @@ static int bpf_task_fd_query(const union bpf_attr *attr,
pid_t pid = attr->task_fd_query.pid;
u32 fd = attr->task_fd_query.fd;
const struct perf_event *event;
- struct files_struct *files;
struct task_struct *task;
struct file *file;
int err;
@@ -3759,23 +3898,11 @@ static int bpf_task_fd_query(const union bpf_attr *attr,
if (!task)
return -ENOENT;
- files = get_files_struct(task);
- put_task_struct(task);
- if (!files)
- return -ENOENT;
-
err = 0;
- spin_lock(&files->file_lock);
- file = fcheck_files(files, fd);
+ file = fget_task(task, fd);
+ put_task_struct(task);
if (!file)
- err = -EBADF;
- else
- get_file(file);
- spin_unlock(&files->file_lock);
- put_files_struct(files);
-
- if (err)
- goto out;
+ return -EBADF;
if (file->f_op == &bpf_link_fops) {
struct bpf_link *link = file->private_data;
@@ -3815,7 +3942,6 @@ out_not_supp:
err = -ENOTSUPP;
put_file:
fput(file);
-out:
return err;
}
@@ -3876,10 +4002,15 @@ err_put:
static int tracing_bpf_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
{
- if (attr->link_create.attach_type == BPF_TRACE_ITER &&
- prog->expected_attach_type == BPF_TRACE_ITER)
- return bpf_iter_link_attach(attr, prog);
+ if (attr->link_create.attach_type != prog->expected_attach_type)
+ return -EINVAL;
+ if (prog->expected_attach_type == BPF_TRACE_ITER)
+ return bpf_iter_link_attach(attr, prog);
+ else if (prog->type == BPF_PROG_TYPE_EXT)
+ return bpf_tracing_prog_attach(prog,
+ attr->link_create.target_fd,
+ attr->link_create.target_btf_id);
return -EINVAL;
}
@@ -3893,18 +4024,25 @@ static int link_create(union bpf_attr *attr)
if (CHECK_ATTR(BPF_LINK_CREATE))
return -EINVAL;
- ptype = attach_type_to_prog_type(attr->link_create.attach_type);
- if (ptype == BPF_PROG_TYPE_UNSPEC)
- return -EINVAL;
-
- prog = bpf_prog_get_type(attr->link_create.prog_fd, ptype);
+ prog = bpf_prog_get(attr->link_create.prog_fd);
if (IS_ERR(prog))
return PTR_ERR(prog);
ret = bpf_prog_attach_check_attach_type(prog,
attr->link_create.attach_type);
if (ret)
- goto err_out;
+ goto out;
+
+ if (prog->type == BPF_PROG_TYPE_EXT) {
+ ret = tracing_bpf_link_attach(attr, prog);
+ goto out;
+ }
+
+ ptype = attach_type_to_prog_type(attr->link_create.attach_type);
+ if (ptype == BPF_PROG_TYPE_UNSPEC || ptype != prog->type) {
+ ret = -EINVAL;
+ goto out;
+ }
switch (ptype) {
case BPF_PROG_TYPE_CGROUP_SKB:
@@ -3932,7 +4070,7 @@ static int link_create(union bpf_attr *attr)
ret = -EINVAL;
}
-err_out:
+out:
if (ret < 0)
bpf_prog_put(prog);
return ret;
@@ -4014,40 +4152,50 @@ static int link_detach(union bpf_attr *attr)
return ret;
}
-static int bpf_link_inc_not_zero(struct bpf_link *link)
+static struct bpf_link *bpf_link_inc_not_zero(struct bpf_link *link)
{
- return atomic64_fetch_add_unless(&link->refcnt, 1, 0) ? 0 : -ENOENT;
+ return atomic64_fetch_add_unless(&link->refcnt, 1, 0) ? link : ERR_PTR(-ENOENT);
}
-#define BPF_LINK_GET_FD_BY_ID_LAST_FIELD link_id
-
-static int bpf_link_get_fd_by_id(const union bpf_attr *attr)
+struct bpf_link *bpf_link_by_id(u32 id)
{
struct bpf_link *link;
- u32 id = attr->link_id;
- int fd, err;
- if (CHECK_ATTR(BPF_LINK_GET_FD_BY_ID))
- return -EINVAL;
-
- if (!capable(CAP_SYS_ADMIN))
- return -EPERM;
+ if (!id)
+ return ERR_PTR(-ENOENT);
spin_lock_bh(&link_idr_lock);
- link = idr_find(&link_idr, id);
/* before link is "settled", ID is 0, pretend it doesn't exist yet */
+ link = idr_find(&link_idr, id);
if (link) {
if (link->id)
- err = bpf_link_inc_not_zero(link);
+ link = bpf_link_inc_not_zero(link);
else
- err = -EAGAIN;
+ link = ERR_PTR(-EAGAIN);
} else {
- err = -ENOENT;
+ link = ERR_PTR(-ENOENT);
}
spin_unlock_bh(&link_idr_lock);
+ return link;
+}
- if (err)
- return err;
+#define BPF_LINK_GET_FD_BY_ID_LAST_FIELD link_id
+
+static int bpf_link_get_fd_by_id(const union bpf_attr *attr)
+{
+ struct bpf_link *link;
+ u32 id = attr->link_id;
+ int fd;
+
+ if (CHECK_ATTR(BPF_LINK_GET_FD_BY_ID))
+ return -EINVAL;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ link = bpf_link_by_id(id);
+ if (IS_ERR(link))
+ return PTR_ERR(link);
fd = bpf_link_new_fd(link);
if (fd < 0)
@@ -4133,6 +4281,68 @@ static int bpf_iter_create(union bpf_attr *attr)
return err;
}
+#define BPF_PROG_BIND_MAP_LAST_FIELD prog_bind_map.flags
+
+static int bpf_prog_bind_map(union bpf_attr *attr)
+{
+ struct bpf_prog *prog;
+ struct bpf_map *map;
+ struct bpf_map **used_maps_old, **used_maps_new;
+ int i, ret = 0;
+
+ if (CHECK_ATTR(BPF_PROG_BIND_MAP))
+ return -EINVAL;
+
+ if (attr->prog_bind_map.flags)
+ return -EINVAL;
+
+ prog = bpf_prog_get(attr->prog_bind_map.prog_fd);
+ if (IS_ERR(prog))
+ return PTR_ERR(prog);
+
+ map = bpf_map_get(attr->prog_bind_map.map_fd);
+ if (IS_ERR(map)) {
+ ret = PTR_ERR(map);
+ goto out_prog_put;
+ }
+
+ mutex_lock(&prog->aux->used_maps_mutex);
+
+ used_maps_old = prog->aux->used_maps;
+
+ for (i = 0; i < prog->aux->used_map_cnt; i++)
+ if (used_maps_old[i] == map) {
+ bpf_map_put(map);
+ goto out_unlock;
+ }
+
+ used_maps_new = kmalloc_array(prog->aux->used_map_cnt + 1,
+ sizeof(used_maps_new[0]),
+ GFP_KERNEL);
+ if (!used_maps_new) {
+ ret = -ENOMEM;
+ goto out_unlock;
+ }
+
+ memcpy(used_maps_new, used_maps_old,
+ sizeof(used_maps_old[0]) * prog->aux->used_map_cnt);
+ used_maps_new[prog->aux->used_map_cnt] = map;
+
+ prog->aux->used_map_cnt++;
+ prog->aux->used_maps = used_maps_new;
+
+ kfree(used_maps_old);
+
+out_unlock:
+ mutex_unlock(&prog->aux->used_maps_mutex);
+
+ if (ret)
+ bpf_map_put(map);
+out_prog_put:
+ bpf_prog_put(prog);
+ return ret;
+}
+
SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, size)
{
union bpf_attr attr;
@@ -4266,6 +4476,9 @@ SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, siz
case BPF_LINK_DETACH:
err = link_detach(&attr);
break;
+ case BPF_PROG_BIND_MAP:
+ err = bpf_prog_bind_map(&attr);
+ break;
default:
err = -EINVAL;
break;