Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759524AbcCVLRe (ORCPT ); Tue, 22 Mar 2016 07:17:34 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:56524 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758711AbcCVKl7 (ORCPT ); Tue, 22 Mar 2016 06:41:59 -0400 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Stefan Hajnoczi , "J. Bruce Fields" , Luis Henriques Subject: [PATCH 3.16.y-ckt 040/142] sunrpc/cache: fix off-by-one in qword_get() Date: Tue, 22 Mar 2016 10:39:29 +0000 Message-Id: <1458643271-4227-41-git-send-email-luis.henriques@canonical.com> In-Reply-To: <1458643271-4227-1-git-send-email-luis.henriques@canonical.com> References: <1458643271-4227-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.16 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1367 Lines: 48 3.16.7-ckt26 -stable review patch. If anyone has any objections, please let me know. ---8<------------------------------------------------------------ From: Stefan Hajnoczi commit b7052cd7bcf3c1478796e93e3dff2b44c9e82943 upstream. The qword_get() function NUL-terminates its output buffer. If the input string is in hex format \xXXXX... and the same length as the output buffer, there is an off-by-one: int qword_get(char **bpp, char *dest, int bufsize) { ... while (len < bufsize) { ... *dest++ = (h << 4) | l; len++; } ... *dest = '\0'; return len; } This patch ensures the NUL terminator doesn't fall outside the output buffer. Signed-off-by: Stefan Hajnoczi Signed-off-by: J. Bruce Fields Signed-off-by: Luis Henriques --- net/sunrpc/cache.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/sunrpc/cache.c b/net/sunrpc/cache.c index 48f14003af10..14d38ec5e53d 100644 --- a/net/sunrpc/cache.c +++ b/net/sunrpc/cache.c @@ -1230,7 +1230,7 @@ int qword_get(char **bpp, char *dest, int bufsize) if (bp[0] == '\\' && bp[1] == 'x') { /* HEX STRING */ bp += 2; - while (len < bufsize) { + while (len < bufsize - 1) { int h, l; h = hex_to_bin(bp[0]);