From nobody Tue Sep 16 17:48:01 2025 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 1CE61C4167B for ; Fri, 30 Dec 2022 13:29:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231391AbiL3N3L (ORCPT ); Fri, 30 Dec 2022 08:29:11 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38268 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229456AbiL3N3J (ORCPT ); Fri, 30 Dec 2022 08:29:09 -0500 Received: from sin.source.kernel.org (sin.source.kernel.org [IPv6:2604:1380:40e1:4800::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7A2EDFC3 for ; Fri, 30 Dec 2022 05:29:08 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by sin.source.kernel.org (Postfix) with ESMTPS id B9EB9CE184C for ; Fri, 30 Dec 2022 13:29:06 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id DCFDAC433EF; Fri, 30 Dec 2022 13:29:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1672406944; bh=niN4//FFQLqT+lccFSrIwvGHtpHQO5j4UdQf+dAxTnM=; h=From:To:Cc:Subject:Date:From; b=Q8Z9F1TdYSn+DHTUxC0tV6CvgAHrJOkO5FS+1xoIU/hT+CkbagXRWd+nGcoQ7G+oY 1QABx5QNGJ4MojljBreW7J6SqybB4ua+Z7K/CoVuZXX9uC0n4P0zo+X55yDOKvUubL PHLVndJhdf+zQxLjSDF/wkNWw59kBNSelibr8zmXgfAVw08xcUNSyG/GDra/lIqWo/ SuMuf7ysAJlpw/vWb/dcZtItBAIsyY7oSAo8iebf5fgaHZN7thPjdHC3MX/i4cLQIL RbU4b4wNyOxl1QazZf9GFWYdu5inJ3fR5cYJa4YloshTyH+R5KZf9wDXHMRlAQuOdk UI6VDL+WnXmeg== From: Chao Yu To: jaegeuk@kernel.org Cc: linux-f2fs-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org, Chao Yu Subject: [PATCH] f2fs: fix error path of f2fs_create_flush_cmd_control() Date: Fri, 30 Dec 2022 21:28:56 +0800 Message-Id: <20221230132856.4248-1-chao@kernel.org> X-Mailer: git-send-email 2.36.1 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" If kthread_run() fails in f2fs_create_flush_cmd_control(), it should not release SM_I(sbi)->fcc_info, otherwise, w/ below testcase, it will cause NULL pointer dereference when accessing SM_I(sbi)->fcc_info in f2fs_issue_flush(). - mount -o noflush_merge /dev/vda /mnt/f2fs - mount -o remount,flush_merge /dev/vda /mnt/f2fs -- kthread_run() fails - dd if=3D/dev/zero of=3D/mnt/f2fs/file bs=3D4k count=3D1 conv=3Dfsync Signed-off-by: Chao Yu --- fs/f2fs/segment.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c index 2646575f43de..7b18e8c02f5d 100644 --- a/fs/f2fs/segment.c +++ b/fs/f2fs/segment.c @@ -663,8 +663,7 @@ int f2fs_create_flush_cmd_control(struct f2fs_sb_info *= sbi) if (IS_ERR(fcc->f2fs_issue_flush)) { int err =3D PTR_ERR(fcc->f2fs_issue_flush); =20 - kfree(fcc); - SM_I(sbi)->fcc_info =3D NULL; + fcc->f2fs_issue_flush =3D NULL; return err; } =20 --=20 2.36.1