[lvc-project] [PATCH 6.12 v2 3/5] tcp_bpf: propagate error code in tcp_bpf_sendmsg()

[Dmitry Antipov]

No upstream commit exists for this patch.

In tcp_bpf_sendmsg(), the value returned by sk_msg_memcopy_from_iter()
is checked for error but not propagated to 'out_err' label, so error
handling may not work as expected. Fix this by assigning error value
to 'err', thus making sure that error won't be silently ignored.

Reported-by: Sashiko <shodan.ai at mcst.ru>
Fixes: 5153a75ef34b ("tcp_bpf: Fix copied value in tcp_bpf_sendmsg")
Signed-off-by: Dmitry Antipov <dmantipov at yandex.ru>
---
Upstream commit is on the way at
https://lore.kernel.org/bpf/179239853943.3290.3841022911205774928@kernel.org/T/#t.
---
 net/ipv4/tcp_bpf.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/net/ipv4/tcp_bpf.c b/net/ipv4/tcp_bpf.c
index abaaf3e70ece..d17b347b852d 100644
--- a/net/ipv4/tcp_bpf.c
+++ b/net/ipv4/tcp_bpf.c
@@ -567,6 +567,7 @@ static int tcp_bpf_sendmsg(struct sock *sk, struct msghdr *msg, size_t size)
 					       copy);
 		if (ret < 0) {
 			sk_msg_trim(sk, msg_tx, osize);
+			err = ret;
 			goto out_err;
 		}
 
-- 
2.56.0