Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S937260AbdCJMWb (ORCPT ); Fri, 10 Mar 2017 07:22:31 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:45252 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S935735AbdCJMW1 (ORCPT ); Fri, 10 Mar 2017 07:22:27 -0500 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Marcelo Ricardo Leitner" , "Xin Long" , "David S. Miller" , "Alexander Popov" Date: Fri, 10 Mar 2017 11:46:23 +0000 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 369/370] sctp: avoid BUG_ON on sctp_wait_for_sndbuf In-Reply-To: X-SA-Exim-Connect-IP: 82.70.136.246 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1346 Lines: 38 3.16.42-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Marcelo Ricardo Leitner commit 2dcab598484185dea7ec22219c76dcdd59e3cb90 upstream. Alexander Popov reported that an application may trigger a BUG_ON in sctp_wait_for_sndbuf if the socket tx buffer is full, a thread is waiting on it to queue more data and meanwhile another thread peels off the association being used by the first thread. This patch replaces the BUG_ON call with a proper error handling. It will return -EPIPE to the original sendmsg call, similarly to what would have been done if the association wasn't found in the first place. Acked-by: Alexander Popov Signed-off-by: Marcelo Ricardo Leitner Reviewed-by: Xin Long Signed-off-by: David S. Miller Signed-off-by: Ben Hutchings --- net/sctp/socket.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/net/sctp/socket.c +++ b/net/sctp/socket.c @@ -6760,7 +6760,8 @@ static int sctp_wait_for_sndbuf(struct s */ release_sock(sk); current_timeo = schedule_timeout(current_timeo); - BUG_ON(sk != asoc->base.sk); + if (sk != asoc->base.sk) + goto do_error; lock_sock(sk); *timeo_p = current_timeo;