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=-8.8 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,INCLUDES_CR_TRAILER,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 BC8F2C433E0 for ; Tue, 16 Mar 2021 18:09:32 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 55037650ED for ; Tue, 16 Mar 2021 18:09:32 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 55037650ED Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id C67C36B0036; Tue, 16 Mar 2021 14:09:31 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id C3EF66B006C; Tue, 16 Mar 2021 14:09:31 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id AE10B6B006E; Tue, 16 Mar 2021 14:09:31 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0022.hostedemail.com [216.40.44.22]) by kanga.kvack.org (Postfix) with ESMTP id 900EB6B0036 for ; Tue, 16 Mar 2021 14:09:31 -0400 (EDT) Received: from smtpin13.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 46E948146 for ; Tue, 16 Mar 2021 18:09:31 +0000 (UTC) X-FDA: 77926524942.13.6229406 Received: from mail-pj1-f51.google.com (mail-pj1-f51.google.com [209.85.216.51]) by imf21.hostedemail.com (Postfix) with ESMTP id DE8CBE0011ED for ; Tue, 16 Mar 2021 18:09:21 +0000 (UTC) Received: by mail-pj1-f51.google.com with SMTP id gb6so11062581pjb.0 for ; Tue, 16 Mar 2021 11:09:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=kwCYvOSg3Vly9TubKoJY2b4cxNmpRuA1nBAv4tTlja4=; b=FPK+AdOS9hUo62UOCNFXU2A1+K/CZd1fEjJIwqzy3sPoMF8jJ4EybgoVZSbkOlHq17 tO0+hGlAf0jm4sqj9jSsNZzj0cPwYg/OVKe3uL1SNZDy3peUzNczwud9VF4BDlhpjYU9 IIm/6P92q+IYe9C29DXSSXMODSCRphGRU2ZZjDTUTaW06pbzzTWWOWhT57U5ykm/OF1q ctHxBzl5UK1FELRGVXFM+mfi233z34v5tSNjB6E2cL0epNp6ykHM1kjJt2S8hv7brK1p Gdd8vquGvMMVx80J7niz/a9ReHe+hYw+xFkcLd3opC2txlbD+M3bE6+JrMVLgVCZYw8/ bUHg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:from:to:cc:subject:message-id :references:mime-version:content-disposition:in-reply-to; bh=kwCYvOSg3Vly9TubKoJY2b4cxNmpRuA1nBAv4tTlja4=; b=XsEqQUmiqDznGtcmFzC7EZ8cV9KtIGx3b9K8gPw5Wb0CmXfUuV4R+uInbgs4mY8vWT TwFpGQEpbUpNYB30TmJUgPsLQ008AnIMZJcPnj0Fpe94IxAJY8ZNtLVg8AHCAJ8Gq0yO +JMOiQkUsJop0kVmeDM2EtNnJ0MGEQgNOXZwbvQuaUiacwi/QIZehl/W4GP0kYY3k2Yo VYibyY8fQFk7N0OuXQDZpCGFd+Vqy8Lh1l74H+hYXGcBETC44R4DpycEWeF2HRJeYrOi jmiX58LADuEe0B0SztjsbM9Y9nLXh/gRsvYTLXtLPg6YC/cyuZKaOb5Z0RMhNzpzI21v i1Dw== X-Gm-Message-State: AOAM531qcswSUHOpsA7ONDH0zgCTydyCEI2EL1nPn0va3pWDA0mTQi8y SHZHt7MKBYZ4M1vzLDSQF4Y= X-Google-Smtp-Source: ABdhPJyHF14TE1cHq52T3t9yf3fdJSczWgvfW7/XvhqjE1oB7I+QVsIy0czPHLhRM5ACUOJkZa5wEQ== X-Received: by 2002:a17:90a:4498:: with SMTP id t24mr320936pjg.78.1615918159691; Tue, 16 Mar 2021 11:09:19 -0700 (PDT) Received: from google.com ([2620:15c:211:201:4160:1d48:d43e:7513]) by smtp.gmail.com with ESMTPSA id p7sm6184768pgj.2.2021.03.16.11.09.16 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 16 Mar 2021 11:09:17 -0700 (PDT) Date: Tue, 16 Mar 2021 11:09:15 -0700 From: Minchan Kim To: Colin King Cc: Andrew Morton , John Hubbard , Stephen Rothwell , Greg Kroah-Hartman , linux-mm@kvack.org, kernel-janitors@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] mm: cma: Fix potential null dereference on pointer cma Message-ID: References: <20210316100433.17665-1-colin.king@canonical.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210316100433.17665-1-colin.king@canonical.com> X-Stat-Signature: q4rw5kmm3u9awrzpuqwdoiipwm7qo45w X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: DE8CBE0011ED Received-SPF: none (gmail.com>: No applicable sender policy available) receiver=imf21; identity=mailfrom; envelope-from=""; helo=mail-pj1-f51.google.com; client-ip=209.85.216.51 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1615918161-32155 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000001, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Tue, Mar 16, 2021 at 10:04:33AM +0000, Colin King wrote: > From: Colin Ian King > > At the start of the function there is a null pointer check on cma > and then branch to error handling label 'out'. The subsequent call > to cma_sysfs_fail_pages_count dereferences cma, hence there is a > potential null pointer deference issue. Fix this by only calling > cma_sysfs_fail_pages_count if cma is not null. > > Addresses-Coverity: ("Dereference after null check") > Fixes: dc4764f7e9ac ("mm: cma: support sysfs") > Signed-off-by: Colin Ian King Acked-by: Minchan Kim