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=-7.0 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 autolearn=no 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 14655C2BB84 for ; Fri, 4 Sep 2020 23:35:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D3F4E208FE for ; Fri, 4 Sep 2020 23:35:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1599262533; bh=ImmSXwO0sJ2R2+sPRnb0B1ILO2z0q4evWpw/pElgZ0I=; h=Date:From:To:Subject:In-Reply-To:Reply-To:List-ID:From; b=XxJHVlEqIg7J1MXq/QDcEgpCu7EgTZkmMOARrcjTbFnSOntSiALkVeC9DN6XIlozW Gr8FxrRclTCh784Q2zLcLGfSWaesmCyKinQs1MX1JPns89bU7NnhMp2TsCVHbEQNTi uxFD1XpxZNE3b/GDa5tBOkdgJDr8mk7ncH3l6hno= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726833AbgIDXfd (ORCPT ); Fri, 4 Sep 2020 19:35:33 -0400 Received: from mail.kernel.org ([198.145.29.99]:38462 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726456AbgIDXfb (ORCPT ); Fri, 4 Sep 2020 19:35:31 -0400 Received: from localhost.localdomain (c-71-198-47-131.hsd1.ca.comcast.net [71.198.47.131]) (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 C9F8620FC3; Fri, 4 Sep 2020 23:35:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1599262531; bh=ImmSXwO0sJ2R2+sPRnb0B1ILO2z0q4evWpw/pElgZ0I=; h=Date:From:To:Subject:In-Reply-To:From; b=I8QicgUy0fedNWi7qQHYjuYF7rvQn+a6MQCdCobc2OCUa5FIqDNxxOFQSO9M7WBEo 91UOJQXtzmCLYUPF86DXq/dEWvYbYyZ5nt0aqc0kBLtYHl6+BPzesAGfrm+PxpCsit cBZax/HrUEFHB5RAWdJlds7mZv/8lvRIZo0szeJ8= Date: Fri, 04 Sep 2020 16:35:30 -0700 From: Andrew Morton To: akpm@linux-foundation.org, cl@linux.com, dongli.zhang@oracle.com, erosca@de.adit-jv.com, iamjoonsoo.kim@lge.com, joe.jin@oracle.com, linux-mm@kvack.org, mm-commits@vger.kernel.org, penberg@kernel.org, rientjes@google.com, stable@vger.kernel.org, torvalds@linux-foundation.org Subject: [patch 03/19] mm: slub: fix conversion of freelist_corrupted() Message-ID: <20200904233530.zhlwFqhIl%akpm@linux-foundation.org> In-Reply-To: <20200904163454.4db0e6ce0c4584d2653678a3@linux-foundation.org> User-Agent: s-nail v14.8.16 Sender: mm-commits-owner@vger.kernel.org Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org From: Eugeniu Rosca Subject: mm: slub: fix conversion of freelist_corrupted() 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/ Link: https://lkml.kernel.org/r/20200824130643.10291-1-erosca@de.adit-jv.com Fixes: 52f23478081ae0 ("mm/slub.c: fix corrupted freechain in deactivate_slab()") Signed-off-by: Eugeniu Rosca Cc: Dongli Zhang Cc: Joe Jin Cc: Christoph Lameter Cc: Pekka Enberg Cc: David Rientjes Cc: Joonsoo Kim Cc: Signed-off-by: Andrew Morton --- mm/slub.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) --- a/mm/slub.c~mm-slub-fix-conversion-of-freelist_corrupted +++ a/mm/slub.c @@ -672,12 +672,12 @@ 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; } @@ -1494,7 +1494,7 @@ 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; } @@ -2184,7 +2184,7 @@ 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 { _