From patchwork Wed Jun 4 09:07:51 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Julia Lawall X-Patchwork-Id: 4292791 Return-Path: X-Original-To: patchwork-linux-sh@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id E37999F777 for ; Wed, 4 Jun 2014 09:14:35 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 1FDBE202F8 for ; Wed, 4 Jun 2014 09:14:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3D34F20272 for ; Wed, 4 Jun 2014 09:14:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751691AbaFDJJ6 (ORCPT ); Wed, 4 Jun 2014 05:09:58 -0400 Received: from mail3-relais-sop.national.inria.fr ([192.134.164.104]:7781 "EHLO mail3-relais-sop.national.inria.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751136AbaFDJJ4 (ORCPT ); Wed, 4 Jun 2014 05:09:56 -0400 X-IronPort-AV: E=Sophos;i="4.98,972,1392159600"; d="scan'208";a="65385488" Received: from palace.lip6.fr (HELO localhost.localdomain) ([132.227.105.202]) by mail3-relais-sop.national.inria.fr with ESMTP/TLS/DHE-RSA-AES256-SHA; 04 Jun 2014 11:09:51 +0200 From: Julia Lawall To: Peter Zijlstra Cc: kernel-janitors@vger.kernel.org, Paul Mackerras , Ingo Molnar , Arnaldo Carvalho de Melo , linux-kernel@vger.kernel.org, linux-sh@vger.kernel.org Subject: [PATCH 1/10] sh: use safer test on the result of find_first_zero_bit Date: Wed, 4 Jun 2014 11:07:51 +0200 Message-Id: <1401872880-23685-2-git-send-email-Julia.Lawall@lip6.fr> X-Mailer: git-send-email 1.8.3.2 In-Reply-To: <1401872880-23685-1-git-send-email-Julia.Lawall@lip6.fr> References: <1401872880-23685-1-git-send-email-Julia.Lawall@lip6.fr> Sender: linux-sh-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-sh@vger.kernel.org X-Spam-Status: No, score=-7.5 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Julia Lawall Find_first_zero_bit considers BITS_PER_LONG bits at a time, and thus may return a larger number than the maximum position argument if that position is not a multiple of BITS_PER_LONG. The semantic match that finds this problem is as follows: (http://coccinelle.lip6.fr/) // @@ expression e1,e2,e3; statement S1,S2; @@ e1 = find_first_zero_bit(e2,e3) ... if (e1 - == + >= e3) S1 else S2 // Signed-off-by: Julia Lawall --- arch/sh/kernel/perf_event.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) -- To unsubscribe from this list: send the line "unsubscribe linux-sh" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html diff -u -p a/arch/sh/kernel/perf_event.c b/arch/sh/kernel/perf_event.c --- a/arch/sh/kernel/perf_event.c +++ b/arch/sh/kernel/perf_event.c @@ -281,7 +281,7 @@ static int sh_pmu_add(struct perf_event if (__test_and_set_bit(idx, cpuc->used_mask)) { idx = find_first_zero_bit(cpuc->used_mask, sh_pmu->num_events); - if (idx == sh_pmu->num_events) + if (idx >= sh_pmu->num_events) goto out; __set_bit(idx, cpuc->used_mask);