From: Eric Dumazet <edumazet@xxxxxxxxxx>
If recv_actor() returns an incorrect value, tcp_read_sock()
might loop forever.
Instead, issue a one time warning and make sure to make progress.
Signed-off-by: Eric Dumazet <edumazet@xxxxxxxxxx>
Acked-by: John Fastabend <john.fastabend@xxxxxxxxx>
Acked-by: Jakub Sitnicki <jakub@xxxxxxxxxxxxxx>
Acked-by: Daniel Borkmann <daniel@xxxxxxxxxxxxx>
---
net/ipv4/tcp.c | 10 ++++++----
1 file changed, 6 insertions(+), 4 deletions(-)
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 02cb275e5487d98b3e124ee102163aac47b2ad6d..28ff2a820f7c935234e5ab7ecd4ed95fb7c5712a 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -1684,11 +1684,13 @@ int tcp_read_sock(struct sock *sk, read_descriptor_t *desc,
if (!copied)
copied = used;
break;
- } else if (used <= len) {
- seq += used;
- copied += used;
- offset += used;
}
+ if (WARN_ON_ONCE(used > len))
+ used = len;
+ seq += used;
+ copied += used;
+ offset += used;
+
/* If recv_actor drops the lock (e.g. TCP splice
* receive) the skb pointer might be invalid when
* getting here: tcp_collapse might have deleted it
--
2.35.1.574.g5d30c73bfb-goog
