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 7A9CFC0650F for ; Mon, 5 Aug 2019 13:22:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4733A2075B for ; Mon, 5 Aug 2019 13:22:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1565011342; bh=lPwyNVnIRzEaWGHLLwcdEhNRYl4mScGqRovi7S8MVyE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=zmjZZM0UETUTrfPbHeTHBBMfbtDemA687Gp6ShAZml7wDhdxjal/GVfE2m4ipwox5 3lMgMae2a0tty4EKarnuTimtHS57ZL9BCL5AqGlkH3TpeMrl+sNaL7KMwFie5vg9oE G4776eX6rOSghbYBiOXUKh+Aem1UjIzrGVBwESaA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730667AbfHENWV (ORCPT ); Mon, 5 Aug 2019 09:22:21 -0400 Received: from mail.kernel.org ([198.145.29.99]:58656 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730649AbfHENWR (ORCPT ); Mon, 5 Aug 2019 09:22:17 -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 9842720651; Mon, 5 Aug 2019 13:22:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1565011337; bh=lPwyNVnIRzEaWGHLLwcdEhNRYl4mScGqRovi7S8MVyE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=cLVylhLb69hE6YfpfQ1dR5I2H/QnsC9mXKrwpmkaiRC1kfarMa/dWiIIkirtCGUpe YYBqCh0wtTk2QTmPAijk+DialGMipAjZqt11EiwWvqB4uchL7cajeD8PaUwyP90h3c WsXK5LFDbJ9/B4p+I+V2uh3KqupsHdN5vOgxw6MM= 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 5.2 055/131] lib/test_string.c: avoid masking memset16/32/64 failures Date: Mon, 5 Aug 2019 15:02:22 +0200 Message-Id: <20190805124955.119100635@linuxfoundation.org> X-Mailer: git-send-email 2.22.0 In-Reply-To: <20190805124951.453337465@linuxfoundation.org> References: <20190805124951.453337465@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 bf8def01ed204..b5117ae596931 100644 --- a/lib/test_string.c +++ b/lib/test_string.c @@ -36,7 +36,7 @@ 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; } @@ -72,7 +72,7 @@ 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; } @@ -108,7 +108,7 @@ 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