From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Stefan Hajnoczi" , "J. Bruce Fields" Date: Tue, 29 Mar 2016 20:18:22 +0100 Message-ID: Subject: [PATCH 3.2 35/62] sunrpc/cache: fix off-by-one in qword_get() In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.2.79-rc1 review patch. If anyone has any objections, please let me know. ------------------ 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: Ben Hutchings --- net/sunrpc/cache.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/net/sunrpc/cache.c +++ b/net/sunrpc/cache.c @@ -1211,7 +1211,7 @@ int qword_get(char **bpp, char *dest, in 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]);