diff options
| author | Eric Dumazet <edumazet@google.com> | 2022-03-02 08:17:23 -0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-03-23 09:01:34 +0100 |
| commit | b630da9e2542973dc0f96efe6760abfd1b8006ea (patch) | |
| tree | 00030753b03336a7b4776adf0edc4a411ab96798 /net | |
| parent | a3d04dd8355dc607fc408775b56ffd3fb6348599 (diff) | |
tcp: make tcp_read_sock() more robust
[ Upstream commit e3d5ea2c011ecb16fb94c56a659364e6b30fac94 ]
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@google.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Jakub Sitnicki <jakub@cloudflare.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/r/20220302161723.3910001-2-eric.dumazet@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'net')
| -rw-r--r-- | net/ipv4/tcp.c | 10 |
1 files changed, 6 insertions, 4 deletions
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index c9f6f28e54f3..a0fd9ef2d2c6 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -1657,11 +1657,13 @@ 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 |