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=-15.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 9511FC433F5 for ; Sat, 18 Sep 2021 06:52:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 61B0C61244 for ; Sat, 18 Sep 2021 06:52:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237420AbhIRGyE (ORCPT ); Sat, 18 Sep 2021 02:54:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57598 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232721AbhIRGyC (ORCPT ); Sat, 18 Sep 2021 02:54:02 -0400 Received: from mail-pf1-x433.google.com (mail-pf1-x433.google.com [IPv6:2607:f8b0:4864:20::433]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 95680C061574 for ; Fri, 17 Sep 2021 23:52:39 -0700 (PDT) Received: by mail-pf1-x433.google.com with SMTP id c1so8352505pfp.10 for ; Fri, 17 Sep 2021 23:52:39 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=2qpn+FUWspl8hHFYBlprQCoE3a7AoXcPYE7SKxAyAXE=; b=bfrHMqribJAIzrW0YTLEN4fPSrSfWSqyiXP6BhUTFZZw6a+h4OjWJJVJHRjsHr2mB+ Z3Xj53+wbtRC+zfGLMhkLJPGaRKkckFpIlanTu7Zl9Q1nzscnySKeLefJg7+h6BecU17 x869Z4Hks91pWLKgwK61fvNneyJ6nf67zGHtlln2qDWacAv7W1PaF5g+IoNagGL4Pwuc I0HxjbByfVQchkNjF0u59XqLTJkqcq/tMdqOjGwZjgfZ8OOJOhIkZwOKb2sbrGtxN2YO KGzzQwjkytlVgQfihEj9+NBgDeIr13l64CaV3qB2MCisKkH/MCC8HsC7GPDbxHqoN6Ri HRMg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=2qpn+FUWspl8hHFYBlprQCoE3a7AoXcPYE7SKxAyAXE=; b=QHDY85SZdRL8d/BvbSCgHG/RoXQw5Kp6kZy1awMkJmfGevy6jGOdBwISA3WYw71oKQ pbo++LRLfdSvqls7mbjn7opXIX+8fV27yxRUd2fGIzGlsbqTpN4d54t/F5qisZTjVyXp uE1n9c5+VtJDD6UcAUSvjmEOZPueNYyktoUQQjO2c+8ey3Ib7mFK1nBPL6gYQpkarKTf xm+BCTbi5E5yoNvqS35snN5iNpLQ9NBIrmUM8nvVbbA25BFuZgQ2byPbrRLX09vCcf34 fRrIKZVcTGQ1AgvIpIX2JAPe9lDYqA8/NH3HDNpzpMlIVwpSKlcGjEnjZh6Ld2twFbBZ 7sFA== X-Gm-Message-State: AOAM531kMlB8d4ZRe93T2almx9vR+KbE8ZKfDIQiPh7SmPeVP1xKmmcg Y5B/CIEDHPRr9pA9iXc7j6g= X-Google-Smtp-Source: ABdhPJzxkJVrIpJgt6OwOH4PLRz0CiB73sVe0RS9mq22otyEJL6mcAoAapPbmy4kH/6KDWBU1XhHbg== X-Received: by 2002:a63:4541:: with SMTP id u1mr13523990pgk.369.1631947959122; Fri, 17 Sep 2021 23:52:39 -0700 (PDT) Received: from localhost.localdomain ([193.203.214.57]) by smtp.gmail.com with ESMTPSA id x8sm7988251pfq.131.2021.09.17.23.52.36 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 17 Sep 2021 23:52:38 -0700 (PDT) From: cgel.zte@gmail.com X-Google-Original-From: yang.guang5@zte.com.cn To: dave.hansen@linux.intel.com Cc: luto@kernel.org, peterz@infradead.org, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, x86@kernel.org, hpa@zytor.com, jan.kiszka@siemens.com, jmoyer@redhat.com, dan.j.williams@intel.com, neilb@suse.de, yang.guang5@zte.com.cn, linux-kernel@vger.kernel.org Subject: [PATCH] Modify the check condition Date: Sat, 18 Sep 2021 06:52:32 +0000 Message-Id: <20210918065232.239336-1-yang.guang5@zte.com.cn> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Yang Guang The vma may be NULL, and accessing the member of vma like "vma->vm_start" in calling follow_phys may occur segmentation fault. So it should check vma at beginning. If vma is null, it will return. And the if condition won't execute "vm->vm_flags". Signed-off-by: Yang Guang --- arch/x86/mm/pat/memtype.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/mm/pat/memtype.c b/arch/x86/mm/pat/memtype.c index 4ba2a3ee4bce..b7108b37b754 100644 --- a/arch/x86/mm/pat/memtype.c +++ b/arch/x86/mm/pat/memtype.c @@ -1089,7 +1089,7 @@ void untrack_pfn(struct vm_area_struct *vma, unsigned long pfn, resource_size_t paddr; unsigned long prot; - if (vma && !(vma->vm_flags & VM_PAT)) + if (!(vma) || !(vma->vm_flags & VM_PAT)) return; /* free the chunk starting from pfn or the whole chunk */ -- 2.25.1