From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,URIBL_SBL,URIBL_SBL_A, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8F289C433FF for ; Mon, 5 Aug 2019 13:10:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6790D216F4 for ; Mon, 5 Aug 2019 13:10:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1565010600; bh=4Oveecdha/pb64ZWvVOdcWAJv5q/swTY08yW+2J80r8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=BdKa1ahnJVzHPvs7HBQ66i/R4k4v1slBPlKqE+aSzE3Zt1J3OlYD5q64N+8H8auhX IfZeVUibOMO1TwxtEeS0lHK26QQMJ3eRxU/0TVrTGryonytnRLkounCgPpYu+1CoSw UPmPzmeFfvQIhPPg9pvdcvaC0L9xdSl52Py5+nq8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729862AbfHENJ7 (ORCPT ); Mon, 5 Aug 2019 09:09:59 -0400 Received: from mail.kernel.org ([198.145.29.99]:48534 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729035AbfHENJx (ORCPT ); Mon, 5 Aug 2019 09:09:53 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 7226F2075B; Mon, 5 Aug 2019 13:09:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1565010593; bh=4Oveecdha/pb64ZWvVOdcWAJv5q/swTY08yW+2J80r8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ZYs4bL+2+rgbMn2Xh+tdSEMknodjPJCyhSqNh+q30gaAlbYCrm8q69q8Y6XEgIgSk OaaPwtruWQw5iPe2HERaulGmqZltBIx8D/dCNPylPbY4S4wL1lX0VTU/Z1V/h0Qe5T zoRCwpmHwxvjpJ5MvFoxl9dN1GIH21HOEmyIwb+U= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Peter Rosin , Andrew Morton , Linus Torvalds , Sasha Levin Subject: [PATCH 4.19 30/74] lib/test_string.c: avoid masking memset16/32/64 failures Date: Mon, 5 Aug 2019 15:02:43 +0200 Message-Id: <20190805124938.186161074@linuxfoundation.org> X-Mailer: git-send-email 2.22.0 In-Reply-To: <20190805124935.819068648@linuxfoundation.org> References: <20190805124935.819068648@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org [ Upstream commit 33d6e0ff68af74be0c846c8e042e84a9a1a0561e ] If a memsetXX implementation is completely broken and fails in the first iteration, when i, j, and k are all zero, the failure is masked as zero is returned. Failing in the first iteration is perhaps the most likely failure, so this makes the tests pretty much useless. Avoid the situation by always setting a random unused bit in the result on failure. Link: http://lkml.kernel.org/r/20190506124634.6807-3-peda@axentia.se Fixes: 03270c13c5ff ("lib/string.c: add testcases for memset16/32/64") Signed-off-by: Peter Rosin Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin --- lib/test_string.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/lib/test_string.c b/lib/test_string.c index 0fcdb82dca866..98a787e7a1fd6 100644 --- a/lib/test_string.c +++ b/lib/test_string.c @@ -35,7 +35,7 @@ static __init int memset16_selftest(void) fail: kfree(p); if (i < 256) - return (i << 24) | (j << 16) | k; + return (i << 24) | (j << 16) | k | 0x8000; return 0; } @@ -71,7 +71,7 @@ static __init int memset32_selftest(void) fail: kfree(p); if (i < 256) - return (i << 24) | (j << 16) | k; + return (i << 24) | (j << 16) | k | 0x8000; return 0; } @@ -107,7 +107,7 @@ static __init int memset64_selftest(void) fail: kfree(p); if (i < 256) - return (i << 24) | (j << 16) | k; + return (i << 24) | (j << 16) | k | 0x8000; return 0; } -- 2.20.1