From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756629AbbAHMO5 (ORCPT ); Thu, 8 Jan 2015 07:14:57 -0500 Received: from mail-la0-f47.google.com ([209.85.215.47]:56386 "EHLO mail-la0-f47.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753834AbbAHMO4 (ORCPT ); Thu, 8 Jan 2015 07:14:56 -0500 From: Rasmus Villemoes To: Andrew Morton , Jiri Kosina , Randy Dunlap Cc: Rasmus Villemoes , linux-kernel@vger.kernel.org Subject: [PATCH 2/4] lib/vsprintf.c: Improve sanity check in vsnprintf() Date: Thu, 8 Jan 2015 13:14:45 +0100 Message-Id: <1420719287-10222-2-git-send-email-linux@rasmusvillemoes.dk> X-Mailer: git-send-email 2.1.3 In-Reply-To: <1420719287-10222-1-git-send-email-linux@rasmusvillemoes.dk> References: <1420719287-10222-1-git-send-email-linux@rasmusvillemoes.dk> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 64 bit, size may very well be huge even if bit 31 happens to be 0. Somehow it doesn't feel right that one can pass a 5 GiB buffer but not a 3 GiB one. So cap at INT_MAX as was probably the intention all along. This is also the made-up value passed by sprintf and vsprintf. Signed-off-by: Rasmus Villemoes --- lib/vsprintf.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/lib/vsprintf.c b/lib/vsprintf.c index 98ad170b10e0..cf12ba86205c 100644 --- a/lib/vsprintf.c +++ b/lib/vsprintf.c @@ -1727,7 +1727,7 @@ int vsnprintf(char *buf, size_t size, const char *fmt, va_list args) /* Reject out-of-range values early. Large positive sizes are used for unknown buffer sizes. */ - if (WARN_ON_ONCE((int) size < 0)) + if (WARN_ON_ONCE(size > INT_MAX)) return 0; str = buf; -- 2.1.3