From nobody Wed Apr 8 21:17:53 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7442EC38A02 for ; Sun, 30 Oct 2022 07:03:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229738AbiJ3HDR (ORCPT ); Sun, 30 Oct 2022 03:03:17 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52810 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229576AbiJ3HDO (ORCPT ); Sun, 30 Oct 2022 03:03:14 -0400 Received: from mail-pf1-x42c.google.com (mail-pf1-x42c.google.com [IPv6:2607:f8b0:4864:20::42c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E274F6380 for ; Sun, 30 Oct 2022 00:03:13 -0700 (PDT) Received: by mail-pf1-x42c.google.com with SMTP id 192so8179680pfx.5 for ; Sun, 30 Oct 2022 00:03:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=DyF/R/2WTrLneukk7kSdKd5EhCLxrsOWmVW7ecTbbfM=; b=YHomcf2498kp/tmkp72Pt2Iup6sbFL7DvV7NfXwhPbU6ZLv/+4FHQvJrfvw1OnVN74 hS0HUxVXnb9p4cnMisRtzLiXm7MwNcW2wohkuUgHYw6lmkjcwhc6n8MOmAhQ3ukz8gHk 5WdR9Hp4Yb+eG22ZhGGT2A9rDn4cCLywl1cmQgCTMzQVlgle2lgtBNWz7cbtzv1SRy3A lN5O6HJnVkX4/MaHOiz62yHDtveVvJtvjsGJ08UBgyDx+QbKocB5xiKulJnZO/7XNWJT FHpQKOglixHOlQsUBejX/uy/50/kRwU19TwwORbqXZc70aziIfoNVnMYtCdFvlVnL0Rh Ls6Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=DyF/R/2WTrLneukk7kSdKd5EhCLxrsOWmVW7ecTbbfM=; b=YAVcqB4oQNJdrqhhGchXRDx5dPGcbblN862NC87btOyn5YYtqybS6zuDGPv6vMfTFp 9J2E2FP/PcUSBjU0wj9HGDS4DU1rOxukeHeueMShmBLcvxAzVbgufhaYA40eoSbAH6J/ iIOVsb3nS1GExAF9XMlyOy7+fuVsktSokVE2IohcE0DRZkPpk+0a/p0xarXG+Y5wPydF fbloDKvk8mLnwWm+38ygJcDvjUlbMVNpHICIHqAWXEHx7e9ZoBjK6Rqa45UD4mZWlyPU PhFMHZtBPSE137WUT9eSlhkzdCI2acwPnW7+xhLCzPPn1w26k4YvU2svD32VD25duRGR rwGw== X-Gm-Message-State: ACrzQf20SGM9ymClrLMpnEijWeXun0AD9qUSQZad+IJCFZ29xoMsXsJW +bzKmToxSiAOZvoaoughdUOIDOwg71Q= X-Google-Smtp-Source: AMsMyM7mtvGzeJGvFc/LlsYuZ38YYkGPpeb2EP7dJoxa51Wm848cYTSCAQcJ+BsuVUZojhzc9k+g3g== X-Received: by 2002:a05:6a00:1582:b0:56d:4bc6:68c7 with SMTP id u2-20020a056a00158200b0056d4bc668c7mr1629218pfk.31.1667113393458; Sun, 30 Oct 2022 00:03:13 -0700 (PDT) Received: from localhost.localdomain ([106.201.172.104]) by smtp.googlemail.com with ESMTPSA id p1-20020a170902e74100b0017a032d7ae4sm2234195plf.104.2022.10.30.00.03.10 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 30 Oct 2022 00:03:13 -0700 (PDT) From: Abdun Nihaal To: almaz.alexandrovich@paragon-software.com Cc: ntfs3@lists.linux.dev, linux-kernel@vger.kernel.org, skhan@linuxfoundation.org, linux-kernel-mentees@lists.linuxfoundation.org, Abdun Nihaal , syzbot+f45957555ed4a808cc7a@syzkaller.appspotmail.com Subject: [PATCH] fs/ntfs3: Fix NULL dereference in ni_write_inode Date: Sun, 30 Oct 2022 12:32:51 +0530 Message-Id: <20221030070251.614970-1-abdun.nihaal@gmail.com> X-Mailer: git-send-email 2.37.3 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" Syzbot reports a NULL dereference in ni_write_inode. When creating a new inode, if allocation fails in mi_init function (called in mi_format_new function), mi->mrec is set to NULL. In the error path of this inode creation, mi->mrec is later dereferenced in ni_write_inode. Add a NULL check to prevent NULL dereference. Link: https://syzkaller.appspot.com/bug?extid=3Df45957555ed4a808cc7a Reported-and-tested-by: syzbot+f45957555ed4a808cc7a@syzkaller.appspotmail.c= om Signed-off-by: Abdun Nihaal --- fs/ntfs3/frecord.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/fs/ntfs3/frecord.c b/fs/ntfs3/frecord.c index 70a80f9412f7..e55bbd209ef8 100644 --- a/fs/ntfs3/frecord.c +++ b/fs/ntfs3/frecord.c @@ -3243,6 +3243,9 @@ int ni_write_inode(struct inode *inode, int sync, con= st char *hint) return 0; } =20 + if (!ni->mi.mrec) + goto out; + if (is_rec_inuse(ni->mi.mrec) && !(sbi->flags & NTFS_FLAGS_LOG_REPLAYING) && inode->i_nlink) { bool modified =3D false; --=20 2.37.3