There is no guarantee that state->sk refers to a full socket.
If refcount transitions to 0, sock_put calls sk_free which then ends up
with garbage fields.
I'd like to thank Oleksandr Natalenko and Jiri Benc for considerable
debug work and pointing out state->sk oddities.
Fixes: ca6fb0651883 ("tcp: attach SYNACK messages to request sockets instead of listener")
Signed-off-by: Florian Westphal <fw@xxxxxxxxx>
---
No reproducer, so there is a chance that the reported crash is caused by
something else. That said, I don't see how sock_put use is safe here.
net/netfilter/nf_queue.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/net/netfilter/nf_queue.c b/net/netfilter/nf_queue.c
index 6d12afabfe8a..178742a110d9 100644
--- a/net/netfilter/nf_queue.c
+++ b/net/netfilter/nf_queue.c
@@ -54,7 +54,7 @@ static void nf_queue_entry_release_refs(struct nf_queue_entry *entry)
dev_put(state->in);
dev_put(state->out);
if (state->sk)
- sock_put(state->sk);
+ sock_gen_put(state->sk);
#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
dev_put(entry->physin);
--
2.34.1
