bpf: add support for bpf_spin_lock to cgroup local storage

Allow 'struct bpf_spin_lock' to reside inside cgroup local storage.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

3 files changed, 6 insertions, 1 deletions

diff --git a/kernel/bpf/local_storage.c b/kernel/bpf/local_storage.c
index 07a34ef562a0..0295427f06e2 100644
--- a/kernel/bpf/local_storage.c
+++ b/kernel/bpf/local_storage.c
@@ -147,6 +147,7 @@ static int cgroup_storage_update_elem(struct bpf_map *map, void *_key,
                 return -ENOMEM;
 
         memcpy(&new->data[0], value, map->value_size);
+        check_and_init_map_lock(map, new->data);
 
         new = xchg(&storage->buf, new);
         kfree_rcu(new, rcu);
@@ -483,6 +484,7 @@ struct bpf_cgroup_storage *bpf_cgroup_storage_alloc(struct bpf_prog *prog,
                 storage->buf = kmalloc_node(size, flags, map->numa_node);
                 if (!storage->buf)
                         goto enomem;
+                check_and_init_map_lock(map, storage->buf->data);
         } else {
                 storage->percpu_buf = __alloc_percpu_gfp(size, 8, flags);
                 if (!storage->percpu_buf)
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index ebf0a673cb83..b29e6dc44650 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -482,7 +482,8 @@ static int map_check_btf(struct bpf_map *map, const struct btf *btf,
 
         if (map_value_has_spin_lock(map)) {
                 if (map->map_type != BPF_MAP_TYPE_HASH &&
-                    map->map_type != BPF_MAP_TYPE_ARRAY)
+                    map->map_type != BPF_MAP_TYPE_ARRAY &&
+                    map->map_type != BPF_MAP_TYPE_CGROUP_STORAGE)
                         return -ENOTSUPP;
                 if (map->spin_lock_off + sizeof(struct bpf_spin_lock) >
                     map->value_size) {
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 38892bdee651..b63bc77af2d1 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -3089,6 +3089,8 @@ static int check_helper_call(struct bpf_verifier_env *env, int func_id, int insn
                 regs[BPF_REG_0].map_ptr = meta.map_ptr;
                 if (fn->ret_type == RET_PTR_TO_MAP_VALUE) {
                         regs[BPF_REG_0].type = PTR_TO_MAP_VALUE;
+                        if (map_value_has_spin_lock(meta.map_ptr))
+                                regs[BPF_REG_0].id = ++env->id_gen;
                 } else {
                         regs[BPF_REG_0].type = PTR_TO_MAP_VALUE_OR_NULL;
                         regs[BPF_REG_0].id = ++env->id_gen;