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=-9.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 55205C433E2 for ; Fri, 11 Sep 2020 14:56:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 225DE22461 for ; Fri, 11 Sep 2020 14:56:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1599836205; bh=msF5bf0BUlSzBRo/Fv0SbhSCTalssUiDIJoh9XsA56g=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=xD5h1hgSlF8CsVmlnVjW4i2J2DibMholh3lkb+pAzij+9v57aIYSYWJgECsPRDQX5 j/pmE0KmHtwfy7qW6jjN0hTPbigMj0q9RsJA6e46WVSs/9wR7dRsCBxmeYTdDRHrH1 TnLyFiuM5mcce/s6cjghldfV1+d2T/lBpPUXpN/Y= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726118AbgIKO4j (ORCPT ); Fri, 11 Sep 2020 10:56:39 -0400 Received: from mail.kernel.org ([198.145.29.99]:54388 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726178AbgIKNCU (ORCPT ); Fri, 11 Sep 2020 09:02:20 -0400 Received: from localhost (83-86-74-64.cable.dynamic.v4.ziggo.nl [83.86.74.64]) (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 3EB1622243; Fri, 11 Sep 2020 12:57:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1599829052; bh=msF5bf0BUlSzBRo/Fv0SbhSCTalssUiDIJoh9XsA56g=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=GYhfyos27EKkXpSwhMU9liHyRCOpWrJBTHwILYEIP+fAkFnKn6mRWhjBd8kozw0cp 3e3c1PzUncUJgTaXEDqnYLR7+Rx5Ncyy3xq+8prjrz4EYGqrRtfGNY4V+eM0Jum0kX qQfTzvBvDOMfwI3xj6NPtErGDGWhYspzc9BU2r00= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Eugeniu Rosca , Andrew Morton , Dongli Zhang , Joe Jin , Christoph Lameter , Pekka Enberg , David Rientjes , Joonsoo Kim , Linus Torvalds Subject: [PATCH 4.9 48/71] mm: slub: fix conversion of freelist_corrupted() Date: Fri, 11 Sep 2020 14:46:32 +0200 Message-Id: <20200911122507.315341477@linuxfoundation.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200911122504.928931589@linuxfoundation.org> References: <20200911122504.928931589@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 From: Eugeniu Rosca commit dc07a728d49cf025f5da2c31add438d839d076c0 upstream. Commit 52f23478081ae0 ("mm/slub.c: fix corrupted freechain in deactivate_slab()") suffered an update when picked up from LKML [1]. Specifically, relocating 'freelist = NULL' into 'freelist_corrupted()' created a no-op statement. Fix it by sticking to the behavior intended in the original patch [1]. In addition, make freelist_corrupted() immune to passing NULL instead of &freelist. The issue has been spotted via static analysis and code review. [1] https://lore.kernel.org/linux-mm/20200331031450.12182-1-dongli.zhang@oracle.com/ Fixes: 52f23478081ae0 ("mm/slub.c: fix corrupted freechain in deactivate_slab()") Signed-off-by: Eugeniu Rosca Signed-off-by: Andrew Morton Cc: Dongli Zhang Cc: Joe Jin Cc: Christoph Lameter Cc: Pekka Enberg Cc: David Rientjes Cc: Joonsoo Kim Cc: Link: https://lkml.kernel.org/r/20200824130643.10291-1-erosca@de.adit-jv.com Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- mm/slub.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) --- a/mm/slub.c +++ b/mm/slub.c @@ -625,12 +625,12 @@ static void slab_fix(struct kmem_cache * } static bool freelist_corrupted(struct kmem_cache *s, struct page *page, - void *freelist, void *nextfree) + void **freelist, void *nextfree) { if ((s->flags & SLAB_CONSISTENCY_CHECKS) && - !check_valid_pointer(s, page, nextfree)) { - object_err(s, page, freelist, "Freechain corrupt"); - freelist = NULL; + !check_valid_pointer(s, page, nextfree) && freelist) { + object_err(s, page, *freelist, "Freechain corrupt"); + *freelist = NULL; slab_fix(s, "Isolate corrupted freechain"); return true; } @@ -1320,7 +1320,7 @@ static inline void dec_slabs_node(struct int objects) {} static bool freelist_corrupted(struct kmem_cache *s, struct page *page, - void *freelist, void *nextfree) + void **freelist, void *nextfree) { return false; } @@ -2040,7 +2040,7 @@ static void deactivate_slab(struct kmem_ * 'freelist' is already corrupted. So isolate all objects * starting at 'freelist'. */ - if (freelist_corrupted(s, page, freelist, nextfree)) + if (freelist_corrupted(s, page, &freelist, nextfree)) break; do {