From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933262AbdBPRzf (ORCPT ); Thu, 16 Feb 2017 12:55:35 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:55444 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933226AbdBPRzc (ORCPT ); Thu, 16 Feb 2017 12:55:32 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Alexander Popov , Marcelo Ricardo Leitner , Xin Long , "David S. Miller" Subject: [PATCH 4.9 21/32] sctp: avoid BUG_ON on sctp_wait_for_sndbuf Date: Thu, 16 Feb 2017 09:54:57 -0800 Message-Id: <20170216175313.321716680@linuxfoundation.org> X-Mailer: git-send-email 2.11.1 In-Reply-To: <20170216175312.436156263@linuxfoundation.org> References: <20170216175312.436156263@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Marcelo Ricardo Leitner [ Upstream commit 2dcab598484185dea7ec22219c76dcdd59e3cb90 ] 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: Greg Kroah-Hartman --- net/sctp/socket.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/net/sctp/socket.c +++ b/net/sctp/socket.c @@ -7427,7 +7427,8 @@ 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;