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Diffstat (limited to 'kernel/bpf/syscall.c')
-rw-r--r--kernel/bpf/syscall.c162
1 files changed, 106 insertions, 56 deletions
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index ef63d26622f2..272071e9112f 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -180,19 +180,6 @@ void bpf_map_init_from_attr(struct bpf_map *map, union bpf_attr *attr)
map->numa_node = bpf_map_attr_numa_node(attr);
}
-int bpf_map_precharge_memlock(u32 pages)
-{
- struct user_struct *user = get_current_user();
- unsigned long memlock_limit, cur;
-
- memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
- cur = atomic_long_read(&user->locked_vm);
- free_uid(user);
- if (cur + pages > memlock_limit)
- return -EPERM;
- return 0;
-}
-
static int bpf_charge_memlock(struct user_struct *user, u32 pages)
{
unsigned long memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
@@ -206,45 +193,62 @@ static int bpf_charge_memlock(struct user_struct *user, u32 pages)
static void bpf_uncharge_memlock(struct user_struct *user, u32 pages)
{
- atomic_long_sub(pages, &user->locked_vm);
+ if (user)
+ atomic_long_sub(pages, &user->locked_vm);
}
-static int bpf_map_init_memlock(struct bpf_map *map)
+int bpf_map_charge_init(struct bpf_map_memory *mem, size_t size)
{
- struct user_struct *user = get_current_user();
+ u32 pages = round_up(size, PAGE_SIZE) >> PAGE_SHIFT;
+ struct user_struct *user;
int ret;
- ret = bpf_charge_memlock(user, map->pages);
+ 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;
}
- map->user = user;
- return ret;
+
+ mem->pages = pages;
+ mem->user = user;
+
+ return 0;
}
-static void bpf_map_release_memlock(struct bpf_map *map)
+void bpf_map_charge_finish(struct bpf_map_memory *mem)
{
- struct user_struct *user = map->user;
- bpf_uncharge_memlock(user, map->pages);
- free_uid(user);
+ 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->user, pages);
+ ret = bpf_charge_memlock(map->memory.user, pages);
if (ret)
return ret;
- map->pages += pages;
+ map->memory.pages += pages;
return ret;
}
void bpf_map_uncharge_memlock(struct bpf_map *map, u32 pages)
{
- bpf_uncharge_memlock(map->user, pages);
- map->pages -= pages;
+ bpf_uncharge_memlock(map->memory.user, pages);
+ map->memory.pages -= pages;
}
static int bpf_map_alloc_id(struct bpf_map *map)
@@ -295,11 +299,13 @@ void bpf_map_free_id(struct bpf_map *map, bool do_idr_lock)
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_release_memlock(map);
+ bpf_map_charge_move(&mem, &map->memory);
security_bpf_map_free(map);
/* implementation dependent freeing */
map->ops->map_free(map);
+ bpf_map_charge_finish(&mem);
}
static void bpf_map_put_uref(struct bpf_map *map)
@@ -387,7 +393,7 @@ static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp)
map->value_size,
map->max_entries,
map->map_flags,
- map->pages * 1ULL << PAGE_SHIFT,
+ map->memory.pages * 1ULL << PAGE_SHIFT,
map->id,
READ_ONCE(map->frozen));
@@ -541,6 +547,7 @@ 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;
@@ -565,7 +572,7 @@ static int map_create(union bpf_attr *attr)
err = bpf_obj_name_cpy(map->name, attr->map_name);
if (err)
- goto free_map_nouncharge;
+ goto free_map;
atomic_set(&map->refcnt, 1);
atomic_set(&map->usercnt, 1);
@@ -575,20 +582,20 @@ static int map_create(union bpf_attr *attr)
if (!attr->btf_value_type_id) {
err = -EINVAL;
- goto free_map_nouncharge;
+ goto free_map;
}
btf = btf_get_by_fd(attr->btf_fd);
if (IS_ERR(btf)) {
err = PTR_ERR(btf);
- goto free_map_nouncharge;
+ goto free_map;
}
err = map_check_btf(map, btf, attr->btf_key_type_id,
attr->btf_value_type_id);
if (err) {
btf_put(btf);
- goto free_map_nouncharge;
+ goto free_map;
}
map->btf = btf;
@@ -600,15 +607,11 @@ static int map_create(union bpf_attr *attr)
err = security_bpf_map_alloc(map);
if (err)
- goto free_map_nouncharge;
-
- err = bpf_map_init_memlock(map);
- if (err)
- goto free_map_sec;
+ goto free_map;
err = bpf_map_alloc_id(map);
if (err)
- goto free_map;
+ goto free_map_sec;
err = bpf_map_new_fd(map, f_flags);
if (err < 0) {
@@ -624,13 +627,13 @@ static int map_create(union bpf_attr *attr)
return err;
-free_map:
- bpf_map_release_memlock(map);
free_map_sec:
security_bpf_map_free(map);
-free_map_nouncharge:
+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;
}
@@ -1573,6 +1576,24 @@ bpf_prog_load_check_attach_type(enum bpf_prog_type prog_type,
case BPF_CGROUP_INET6_CONNECT:
case BPF_CGROUP_UDP4_SENDMSG:
case BPF_CGROUP_UDP6_SENDMSG:
+ case BPF_CGROUP_UDP4_RECVMSG:
+ case BPF_CGROUP_UDP6_RECVMSG:
+ return 0;
+ default:
+ return -EINVAL;
+ }
+ case BPF_PROG_TYPE_CGROUP_SKB:
+ switch (expected_attach_type) {
+ case BPF_CGROUP_INET_INGRESS:
+ case BPF_CGROUP_INET_EGRESS:
+ return 0;
+ default:
+ return -EINVAL;
+ }
+ case BPF_PROG_TYPE_CGROUP_SOCKOPT:
+ switch (expected_attach_type) {
+ case BPF_CGROUP_SETSOCKOPT:
+ case BPF_CGROUP_GETSOCKOPT:
return 0;
default:
return -EINVAL;
@@ -1596,7 +1617,9 @@ static int bpf_prog_load(union bpf_attr *attr, union bpf_attr __user *uattr)
if (CHECK_ATTR(BPF_PROG_LOAD))
return -EINVAL;
- if (attr->prog_flags & ~(BPF_F_STRICT_ALIGNMENT | BPF_F_ANY_ALIGNMENT))
+ if (attr->prog_flags & ~(BPF_F_STRICT_ALIGNMENT |
+ BPF_F_ANY_ALIGNMENT |
+ BPF_F_TEST_RND_HI32))
return -EINVAL;
if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) &&
@@ -1666,7 +1689,7 @@ static int bpf_prog_load(union bpf_attr *attr, union bpf_attr __user *uattr)
if (err < 0)
goto free_prog;
- prog->aux->load_time = ktime_get_boot_ns();
+ prog->aux->load_time = ktime_get_boottime_ns();
err = bpf_obj_name_cpy(prog->aux->name, attr->prog_name);
if (err)
goto free_prog;
@@ -1684,20 +1707,26 @@ static int bpf_prog_load(union bpf_attr *attr, union bpf_attr __user *uattr)
if (err)
goto free_used_maps;
- err = bpf_prog_new_fd(prog);
- if (err < 0) {
- /* failed to allocate fd.
- * bpf_prog_put() is needed because the above
- * bpf_prog_alloc_id() has published the prog
- * to the userspace and the userspace may
- * have refcnt-ed it through BPF_PROG_GET_FD_BY_ID.
- */
- bpf_prog_put(prog);
- return err;
- }
-
+ /* Upon success of bpf_prog_alloc_id(), the BPF prog is
+ * effectively publicly exposed. However, retrieving via
+ * bpf_prog_get_fd_by_id() will take another reference,
+ * therefore it cannot be gone underneath us.
+ *
+ * Only for the time /after/ successful bpf_prog_new_fd()
+ * and before returning to userspace, we might just hold
+ * one reference and any parallel close on that fd could
+ * rip everything out. Hence, below notifications must
+ * happen before bpf_prog_new_fd().
+ *
+ * Also, any failure handling from this point onwards must
+ * be using bpf_prog_put() given the program is exposed.
+ */
bpf_prog_kallsyms_add(prog);
perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_LOAD, 0);
+
+ err = bpf_prog_new_fd(prog);
+ if (err < 0)
+ bpf_prog_put(prog);
return err;
free_used_maps:
@@ -1825,7 +1854,12 @@ static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog,
switch (prog->type) {
case BPF_PROG_TYPE_CGROUP_SOCK:
case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
+ case BPF_PROG_TYPE_CGROUP_SOCKOPT:
return attach_type == prog->expected_attach_type ? 0 : -EINVAL;
+ case BPF_PROG_TYPE_CGROUP_SKB:
+ return prog->enforce_expected_attach_type &&
+ prog->expected_attach_type != attach_type ?
+ -EINVAL : 0;
default:
return 0;
}
@@ -1867,6 +1901,8 @@ static int bpf_prog_attach(const union bpf_attr *attr)
case BPF_CGROUP_INET6_CONNECT:
case BPF_CGROUP_UDP4_SENDMSG:
case BPF_CGROUP_UDP6_SENDMSG:
+ case BPF_CGROUP_UDP4_RECVMSG:
+ case BPF_CGROUP_UDP6_RECVMSG:
ptype = BPF_PROG_TYPE_CGROUP_SOCK_ADDR;
break;
case BPF_CGROUP_SOCK_OPS:
@@ -1891,6 +1927,10 @@ static int bpf_prog_attach(const union bpf_attr *attr)
case BPF_CGROUP_SYSCTL:
ptype = BPF_PROG_TYPE_CGROUP_SYSCTL;
break;
+ case BPF_CGROUP_GETSOCKOPT:
+ case BPF_CGROUP_SETSOCKOPT:
+ ptype = BPF_PROG_TYPE_CGROUP_SOCKOPT;
+ break;
default:
return -EINVAL;
}
@@ -1952,6 +1992,8 @@ static int bpf_prog_detach(const union bpf_attr *attr)
case BPF_CGROUP_INET6_CONNECT:
case BPF_CGROUP_UDP4_SENDMSG:
case BPF_CGROUP_UDP6_SENDMSG:
+ case BPF_CGROUP_UDP4_RECVMSG:
+ case BPF_CGROUP_UDP6_RECVMSG:
ptype = BPF_PROG_TYPE_CGROUP_SOCK_ADDR;
break;
case BPF_CGROUP_SOCK_OPS:
@@ -1972,6 +2014,10 @@ static int bpf_prog_detach(const union bpf_attr *attr)
case BPF_CGROUP_SYSCTL:
ptype = BPF_PROG_TYPE_CGROUP_SYSCTL;
break;
+ case BPF_CGROUP_GETSOCKOPT:
+ case BPF_CGROUP_SETSOCKOPT:
+ ptype = BPF_PROG_TYPE_CGROUP_SOCKOPT;
+ break;
default:
return -EINVAL;
}
@@ -2003,9 +2049,13 @@ static int bpf_prog_query(const union bpf_attr *attr,
case BPF_CGROUP_INET6_CONNECT:
case BPF_CGROUP_UDP4_SENDMSG:
case BPF_CGROUP_UDP6_SENDMSG:
+ case BPF_CGROUP_UDP4_RECVMSG:
+ case BPF_CGROUP_UDP6_RECVMSG:
case BPF_CGROUP_SOCK_OPS:
case BPF_CGROUP_DEVICE:
case BPF_CGROUP_SYSCTL:
+ case BPF_CGROUP_GETSOCKOPT:
+ case BPF_CGROUP_SETSOCKOPT:
break;
case BPF_LIRC_MODE2:
return lirc_prog_query(attr, uattr);