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@xxxxxxxxxx>
Signed-off-by: Stanislav Fomichev <sdf@xxxxxxxxxx>
---
kernel/bpf/syscall.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
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]),
--
2.28.0.806.g8561365e88-goog
