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[2620:137:e000::1:20]) by mx.google.com with ESMTP id xd2-20020a170907078200b007acf3aed468si13034774ejb.786.2022.12.15.01.46.32; Thu, 15 Dec 2022 01:46:55 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229625AbiLOJjs (ORCPT + 99 others); Thu, 15 Dec 2022 04:39:48 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42212 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229471AbiLOJjr (ORCPT ); Thu, 15 Dec 2022 04:39:47 -0500 Received: from mail.astralinux.ru (mail.astralinux.ru [217.74.38.119]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4B06B1BEA5 for ; Thu, 15 Dec 2022 01:39:43 -0800 (PST) Received: from localhost (localhost [127.0.0.1]) by mail.astralinux.ru (Postfix) with ESMTP id DA6A61863D96; Thu, 15 Dec 2022 12:39:38 +0300 (MSK) Received: from mail.astralinux.ru ([127.0.0.1]) by localhost (rbta-msk-vsrv-mail01.astralinux.ru [127.0.0.1]) (amavisd-new, port 10032) with ESMTP id LOgah4IMWUXS; Thu, 15 Dec 2022 12:39:38 +0300 (MSK) Received: from localhost (localhost [127.0.0.1]) by mail.astralinux.ru (Postfix) with ESMTP id 84C451863C60; Thu, 15 Dec 2022 12:39:38 +0300 (MSK) X-Virus-Scanned: amavisd-new at astralinux.ru Received: from mail.astralinux.ru ([127.0.0.1]) by localhost (rbta-msk-vsrv-mail01.astralinux.ru [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id E2TjqXzuL3PY; Thu, 15 Dec 2022 12:39:38 +0300 (MSK) Received: from rbta-msk-lt-106062.astralinux.ru (unknown [10.177.20.20]) by mail.astralinux.ru (Postfix) with ESMTPSA id CAFF61863D96; Thu, 15 Dec 2022 12:39:37 +0300 (MSK) From: Anastasia Belova To: Andrew Morton Cc: Anastasia Belova , Max Filippov , Ingo Molnar , Vineet Gupta , "Russell King (Oracle)" , Geert Uytterhoeven , linux-mm@kvack.org, linux-kernel@vger.kernel.org, lvc-project@linuxtesting.org Subject: [PATCH] mm: Add check for NULL for unlocked in fixup_user_fault Date: Thu, 15 Dec 2022 12:39:30 +0300 Message-Id: <20221215093930.22026-1-abelova@astralinux.ru> X-Mailer: git-send-email 2.30.2 MIME-Version: 1.0 X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00,SPF_HELO_NONE, SPF_PASS autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1752272853539111484?= X-GMAIL-MSGID: =?utf-8?q?1752272853539111484?= Check unlocked for NULL before dereference. Found by Linux Verification Center (linuxtesting.org) with SVACE. Fixes: d92725256b4f ("mm: avoid unnecessary page fault retires on shared memory types") Signed-off-by: Anastasia Belova --- mm/gup.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/mm/gup.c b/mm/gup.c index f212d571b563..905d5fb64c4c 100644 --- a/mm/gup.c +++ b/mm/gup.c @@ -1282,7 +1282,8 @@ int fixup_user_fault(struct mm_struct *mm, * could tell the callers so they do not need to unlock. */ mmap_read_lock(mm); - *unlocked = true; + if (unlocked) + *unlocked = true; return 0; }