diff options
| author | Stanislav Fomichev <sdf@google.com> | 2020-10-02 17:25:44 -0700 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2020-10-02 19:21:25 -0700 |
| commit | 1028ae4069991e26d1522e957939fb61d2da1d12 (patch) | |
| tree | 3515e99b6d9dafa966d02e423f092d6379d7998f | |
| parent | fb91db01c652ba9391f67c21db2d5260448b3efd (diff) | |
bpf: Deref map in BPF_PROG_BIND_MAP when it's already used
We are missing a deref for the case when we are doing BPF_PROG_BIND_MAP
on a map that's being already held by the program.
There is 'if (ret) bpf_map_put(map)' below which doesn't trigger
because we don't consider this an error.
Let's add missing bpf_map_put() for this specific condition.
Fixes: ef15314aa5de ("bpf: Add BPF_PROG_BIND_MAP syscall")
Reported-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20201003002544.3601440-1-sdf@google.com
| -rw-r--r-- | kernel/bpf/syscall.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index f1528c2a6927..1110ecd7d1f3 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -4323,8 +4323,10 @@ static int bpf_prog_bind_map(union bpf_attr *attr) used_maps_old = prog->aux->used_maps; for (i = 0; i < prog->aux->used_map_cnt; i++) - if (used_maps_old[i] == map) + 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]), |