bpf: check NULL for sk_to_full_sk() return value
When req->rsk_listener is NULL, sk_to_full_sk() returns
NULL too, so we have to check its return value against
NULL here.
Fixes: 40304b2a1567 ("bpf: BPF support for sock_ops")
Reported-by: David Ahern <dsahern@gmail.com>
Tested-by: David Ahern <dsahern@gmail.com>
Cc: Lawrence Brakmo <brakmo@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/bpf-cgroup.h b/include/linux/bpf-cgroup.h
index 360c082..d41d40a 100644
--- a/include/linux/bpf-cgroup.h
+++ b/include/linux/bpf-cgroup.h
@@ -85,7 +85,7 @@
int __ret = 0; \
if (cgroup_bpf_enabled && (sock_ops)->sk) { \
typeof(sk) __sk = sk_to_full_sk((sock_ops)->sk); \
- if (sk_fullsock(__sk)) \
+ if (__sk && sk_fullsock(__sk)) \
__ret = __cgroup_bpf_run_filter_sock_ops(__sk, \
sock_ops, \
BPF_CGROUP_SOCK_OPS); \