From 9cb3144045343e7e66cac55e517feec9c286d392 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Sat, 13 Feb 2021 06:26:34 -0800 Subject: tcp: tcp_data_ready() must look at SOCK_DONE commit 39354eb29f597aa01b3d51ccc8169cf183c4367f upstream. My prior cleanup missed that tcp_data_ready() has to look at SOCK_DONE. Otherwise, an application using SO_RCVLOWAT will not get EPOLLIN event if a FIN is received in the middle of expected payload. The reason SOCK_DONE is not examined in tcp_epollin_ready() is that tcp_poll() catches the FIN because tcp_fin() is also setting RCV_SHUTDOWN into sk->sk_shutdown Fixes: 05dc72aba364 ("tcp: factorize logic into tcp_epollin_ready()") Signed-off-by: Eric Dumazet Reported-by: Wei Wang Cc: Arjun Roy Reviewed-by: Wei Wang Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/ipv4/tcp_input.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net') diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 318fdeb1deef..c874ed9484b5 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -5028,7 +5028,7 @@ err: void tcp_data_ready(struct sock *sk) { - if (tcp_epollin_ready(sk, sk->sk_rcvlowat)) + if (tcp_epollin_ready(sk, sk->sk_rcvlowat) || sock_flag(sk, SOCK_DONE)) sk->sk_data_ready(sk); } -- cgit v1.2.3