From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1032725Ab2CPK2V (ORCPT ); Fri, 16 Mar 2012 06:28:21 -0400 Received: from mx1.redhat.com ([209.132.183.28]:29944 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1031019Ab2CPK2T (ORCPT ); Fri, 16 Mar 2012 06:28:19 -0400 Organization: Red Hat UK Ltd. Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903 From: David Howells Subject: [PATCH 1/2] afs: Read of file returns EBADMSG To: torvalds@linux-foundation.org Cc: linux-afs@lists.infradead.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, Anton Blanchard , David Howells , Date: Fri, 16 Mar 2012 10:28:07 +0000 Message-ID: <20120316102807.21424.24579.stgit@warthog.procyon.org.uk> User-Agent: StGIT/0.14.3 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Anton Blanchard A read of a large file on an afs mount failed: # cat junk.file > /dev/null cat: junk.file: Bad message Looking at the trace, call->offset wrapped since it is only an unsigned short. In afs_extract_data: _enter("{%u},{%zu},%d,,%zu", call->offset, len, last, count); ... if (call->offset < count) { if (last) { _leave(" = -EBADMSG [%d < %zu]", call->offset, count); return -EBADMSG; } Which matches the trace: [cat ] ==> afs_extract_data({65132},{524},1,,65536) [cat ] <== afs_extract_data() = -EBADMSG [0 < 65536] call->offset went from 65132 to 0. Fix this by making call->offset an unsigned int. Signed-off-by: Anton Blanchard Signed-off-by: David Howells Cc: --- fs/afs/internal.h | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/fs/afs/internal.h b/fs/afs/internal.h index d2b0888..a306bb6 100644 --- a/fs/afs/internal.h +++ b/fs/afs/internal.h @@ -109,7 +109,7 @@ struct afs_call { unsigned reply_size; /* current size of reply */ unsigned first_offset; /* offset into mapping[first] */ unsigned last_to; /* amount of mapping[last] */ - unsigned short offset; /* offset into received data store */ + unsigned offset; /* offset into received data store */ unsigned char unmarshall; /* unmarshalling phase */ bool incoming; /* T if incoming call */ bool send_pages; /* T if data from mapping should be sent */