From dfbafc995304ebb9a9b03f65083e6e9cea143b20 Mon Sep 17 00:00:00 2001 From: Sabrina Dubroca Date: Fri, 24 Jul 2015 18:19:25 +0200 Subject: tcp: fix recv with flags MSG_WAITALL | MSG_PEEK Currently, tcp_recvmsg enters a busy loop in sk_wait_data if called with flags = MSG_WAITALL | MSG_PEEK. sk_wait_data waits for sk_receive_queue not empty, but in this case, the receive queue is not empty, but does not contain any skb that we can use. Add a "last skb seen on receive queue" argument to sk_wait_data, so that it sleeps until the receive queue has new skbs. Link: https://bugzilla.kernel.org/show_bug.cgi?id=99461 Link: https://sourceware.org/bugzilla/show_bug.cgi?id=18493 Link: https://bugzilla.redhat.com/show_bug.cgi?id=1205258 Reported-by: Enrico Scholz Reported-by: Dan Searle Signed-off-by: Sabrina Dubroca Acked-by: Eric Dumazet Signed-off-by: David S. Miller --- net/llc/af_llc.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'net/llc') diff --git a/net/llc/af_llc.c b/net/llc/af_llc.c index 8fd9febaa5ba..8dab4e569571 100644 --- a/net/llc/af_llc.c +++ b/net/llc/af_llc.c @@ -613,7 +613,7 @@ static int llc_wait_data(struct sock *sk, long timeo) if (signal_pending(current)) break; rc = 0; - if (sk_wait_data(sk, &timeo)) + if (sk_wait_data(sk, &timeo, NULL)) break; } return rc; @@ -802,7 +802,7 @@ static int llc_ui_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, release_sock(sk); lock_sock(sk); } else - sk_wait_data(sk, &timeo); + sk_wait_data(sk, &timeo, NULL); if ((flags & MSG_PEEK) && peek_seq != llc->copied_seq) { net_dbg_ratelimited("LLC(%s:%d): Application bug, race in MSG_PEEK\n", -- cgit v1.2.1