From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760246Ab2CUVSq (ORCPT ); Wed, 21 Mar 2012 17:18:46 -0400 Received: from mail-pz0-f46.google.com ([209.85.210.46]:63855 "EHLO mail-pz0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758965Ab2CUVSi (ORCPT ); Wed, 21 Mar 2012 17:18:38 -0400 Message-Id: <20120321211533.007810519@linuxfoundation.org> User-Agent: quilt/0.60-19.1 Date: Wed, 21 Mar 2012 14:15:35 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Anton Blanchard , David Howells Subject: [ 3/9] afs: Remote abort can cause BUG in rxrpc code In-Reply-To: <20120321211539.GA28899@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.2-stable review patch. If anyone has any objections, please let me know. ------------------ From: Anton Blanchard commit c0173863528a8c9212c53e080d63a1aaae5ef4f4 upstream. When writing files to afs I sometimes hit a BUG: kernel BUG at fs/afs/rxrpc.c:179! With a backtrace of: afs_free_call afs_make_call afs_fs_store_data afs_vnode_store_data afs_write_back_from_locked_page afs_writepages_region afs_writepages The cause is: ASSERT(skb_queue_empty(&call->rx_queue)); Looking at a tcpdump of the session the abort happens because we are exceeding our disk quota: rx abort fs reply store-data error diskquota exceeded (32) So the abort error is valid. We hit the BUG because we haven't freed all the resources for the call. By freeing any skbs in call->rx_queue before calling afs_free_call we avoid hitting leaking memory and avoid hitting the BUG. Signed-off-by: Anton Blanchard Signed-off-by: David Howells Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- fs/afs/rxrpc.c | 3 +++ 1 file changed, 3 insertions(+) --- a/fs/afs/rxrpc.c +++ b/fs/afs/rxrpc.c @@ -314,6 +314,7 @@ int afs_make_call(struct in_addr *addr, struct msghdr msg; struct kvec iov[1]; int ret; + struct sk_buff *skb; _enter("%x,{%d},", addr->s_addr, ntohs(call->port)); @@ -380,6 +381,8 @@ int afs_make_call(struct in_addr *addr, error_do_abort: rxrpc_kernel_abort_call(rxcall, RX_USER_ABORT); + while ((skb = skb_dequeue(&call->rx_queue))) + afs_free_skb(skb); rxrpc_kernel_end_call(rxcall); call->rxcall = NULL; error_kill_call: