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=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_RED autolearn=ham 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 C11F7C43333 for ; Sat, 13 Mar 2021 05:08:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 98C0364FC9 for ; Sat, 13 Mar 2021 05:08:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231795AbhCMFIM (ORCPT ); Sat, 13 Mar 2021 00:08:12 -0500 Received: from mail.kernel.org ([198.145.29.99]:42040 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231906AbhCMFH6 (ORCPT ); Sat, 13 Mar 2021 00:07:58 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id D1C2564E41; Sat, 13 Mar 2021 05:07:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1615612078; bh=k+HOF3cJEROp2rXFGAtK31itT+MlrIOtk1wuYU85+3s=; h=Date:From:To:Subject:In-Reply-To:From; b=hV3gFv+kfitK3UHsnt/eCqO4LeQHXAP8dsSjEjXD3zk4eZ72jmI+aC7JMCxFg/Wfp jg0DXgcJjdvnhM5NIySHtvNPDVmN3dGe822LqZ4FoS0BIfX0XTzTBLsVQYsh/S+ftl hdElAj3sFrXiR4gS2CdMJAxSie2cdJhdrteMB66E= Date: Fri, 12 Mar 2021 21:07:53 -0800 From: Andrew Morton To: akpm@linux-foundation.org, andreyknvl@google.com, dvyukov@google.com, elver@google.com, glider@google.com, jannh@google.com, linux-mm@kvack.org, mm-commits@vger.kernel.org, torvalds@linux-foundation.org Subject: [patch 16/29] kfence, slab: fix cache_alloc_debugcheck_after() for bulk allocations Message-ID: <20210313050753.8pD6LGmHC%akpm@linux-foundation.org> In-Reply-To: <20210312210632.9b7d62973d72a56fb13c7a03@linux-foundation.org> User-Agent: s-nail v14.8.16 Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org From: Marco Elver Subject: kfence, slab: fix cache_alloc_debugcheck_after() for bulk allocations cache_alloc_debugcheck_after() performs checks on an object, including adjusting the returned pointer. None of this should apply to KFENCE objects. While for non-bulk allocations, the checks are skipped when we allocate via KFENCE, for bulk allocations cache_alloc_debugcheck_after() is called via cache_alloc_debugcheck_after_bulk(). Fix it by skipping cache_alloc_debugcheck_after() for KFENCE objects. Link: https://lkml.kernel.org/r/20210304205256.2162309-1-elver@google.com Signed-off-by: Marco Elver Cc: Alexander Potapenko Cc: Dmitry Vyukov Cc: Andrey Konovalov Cc: Jann Horn Signed-off-by: Andrew Morton --- mm/slab.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/mm/slab.c~kfence-slab-fix-cache_alloc_debugcheck_after-for-bulk-allocations +++ a/mm/slab.c @@ -2992,7 +2992,7 @@ static void *cache_alloc_debugcheck_afte gfp_t flags, void *objp, unsigned long caller) { WARN_ON_ONCE(cachep->ctor && (flags & __GFP_ZERO)); - if (!objp) + if (!objp || is_kfence_address(objp)) return objp; if (cachep->flags & SLAB_POISON) { check_poison_obj(cachep, objp); _