From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752976AbbCXREs (ORCPT ); Tue, 24 Mar 2015 13:04:48 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:33483 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S964935AbbCXREn (ORCPT ); Tue, 24 Mar 2015 13:04:43 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, JeHyeon Yeon , David Sterba Subject: [PATCH 3.19 037/123] LZ4 : fix the data abort issue Date: Tue, 24 Mar 2015 16:45:46 +0100 Message-Id: <20150324154425.762235860@linuxfoundation.org> X-Mailer: git-send-email 2.3.3 In-Reply-To: <20150324154423.655554012@linuxfoundation.org> References: <20150324154423.655554012@linuxfoundation.org> User-Agent: quilt/0.64 MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: JeHyeon Yeon commit d5e7cafd69da24e6d6cc988fab6ea313a2577efc upstream. If the part of the compression data are corrupted, or the compression data is totally fake, the memory access over the limit is possible. This is the log from my system usning lz4 decompression. [6502]data abort, halting [6503]r0 0x00000000 r1 0x00000000 r2 0xdcea0ffc r3 0xdcea0ffc [6509]r4 0xb9ab0bfd r5 0xdcea0ffc r6 0xdcea0ff8 r7 0xdce80000 [6515]r8 0x00000000 r9 0x00000000 r10 0x00000000 r11 0xb9a98000 [6522]r12 0xdcea1000 usp 0x00000000 ulr 0x00000000 pc 0x820149bc [6528]spsr 0x400001f3 and the memory addresses of some variables at the moment are ref:0xdcea0ffc, op:0xdcea0ffc, oend:0xdcea1000 As you can see, COPYLENGH is 8bytes, so @ref and @op can access the momory over @oend. Signed-off-by: JeHyeon Yeon Reviewed-by: David Sterba Signed-off-by: Greg Kroah-Hartman Signed-off-by: Greg Kroah-Hartman --- lib/lz4/lz4_decompress.c | 3 +++ 1 file changed, 3 insertions(+) --- a/lib/lz4/lz4_decompress.c +++ b/lib/lz4/lz4_decompress.c @@ -139,6 +139,9 @@ static int lz4_uncompress(const char *so /* Error: request to write beyond destination buffer */ if (cpy > oend) goto _output_error; + if ((ref + COPYLENGTH) > oend || + (op + COPYLENGTH) > oend) + goto _output_error; LZ4_SECURECOPY(ref, op, (oend - COPYLENGTH)); while (op < cpy) *op++ = *ref++;