From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2B5793382C7; Mon, 20 Apr 2026 16:04:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776701044; cv=none; b=XiiyeGt8UM5T0+bZmJWo/0kKZtXaCI1xDFm7M9STnwvYWeYAk7oA/Sebrs+bZSPAHR/AavkZhUe3l2TQUGO4vbOISs645IcRe47YdySN/dHLuapMqi9qte3dxVZs+1POpo/Tl4HqRmRfH+vxgV1VBqyWCzDu0qDQpbcoJQEzsos= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776701044; c=relaxed/simple; bh=K+WoCHO7xgTE3Y5cBn2OI5d+aSqb061TSIdpoi1zTxY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=BycElH+iyVqc/bh5EMQHeQFCEjrZAdKTt27VxzUeAcFE6jJQaodLoupqpi/qw+Mo2peaCvoq5XCSgpXELS91ipGaZC1zziAdqUqZ9GzT3ppCXrgbUQcHxcOtWm1A68WzN85g6LlG1v0J8287uKJ9++OAPFgeoXAhTW91HIHorrE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=YpqJDxa0; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="YpqJDxa0" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8B7E2C2BCB4; Mon, 20 Apr 2026 16:04:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1776701044; bh=K+WoCHO7xgTE3Y5cBn2OI5d+aSqb061TSIdpoi1zTxY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=YpqJDxa0DINT+gGkNfe35ZogfW92OhOVywrr258lQ67tCHG2D4Rf+5XIxF9bzEoFK VvdwYg2lMhpxjO9VCHyTeUfvAi8lzcd6bCHurv19B1Htb9Y5tcnUU2DhmVWdHzEWAY kNwyYhq4Tu/DGXHJbZl8L9C6UjQXu7YPmTWwegaQ= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, syzbot+67b90111784a3eac8c04@syzkaller.appspotmail.com, Joseph Qi , Heming Zhao , Mark Fasheh , Joel Becker , Junxiao Bi , Joseph Qi , Changwei Ge , Jun Piao , Andrew Morton Subject: [PATCH 6.18 160/198] ocfs2: fix possible deadlock between unlink and dio_end_io_write Date: Mon, 20 Apr 2026 17:42:19 +0200 Message-ID: <20260420153941.367896116@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260420153935.605963767@linuxfoundation.org> References: <20260420153935.605963767@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Joseph Qi commit b02da26a992db0c0e2559acbda0fc48d4a2fd337 upstream. ocfs2_unlink takes orphan dir inode_lock first and then ip_alloc_sem, while in ocfs2_dio_end_io_write, it acquires these locks in reverse order. This creates an ABBA lock ordering violation on lock classes ocfs2_sysfile_lock_key[ORPHAN_DIR_SYSTEM_INODE] and ocfs2_file_ip_alloc_sem_key. Lock Chain #0 (orphan dir inode_lock -> ip_alloc_sem): ocfs2_unlink ocfs2_prepare_orphan_dir ocfs2_lookup_lock_orphan_dir inode_lock(orphan_dir_inode) <- lock A __ocfs2_prepare_orphan_dir ocfs2_prepare_dir_for_insert ocfs2_extend_dir ocfs2_expand_inline_dir down_write(&oi->ip_alloc_sem) <- Lock B Lock Chain #1 (ip_alloc_sem -> orphan dir inode_lock): ocfs2_dio_end_io_write down_write(&oi->ip_alloc_sem) <- Lock B ocfs2_del_inode_from_orphan() inode_lock(orphan_dir_inode) <- Lock A Deadlock Scenario: CPU0 (unlink) CPU1 (dio_end_io_write) ------ ------ inode_lock(orphan_dir_inode) down_write(ip_alloc_sem) down_write(ip_alloc_sem) inode_lock(orphan_dir_inode) Since ip_alloc_sem is to protect allocation changes, which is unrelated with operations in ocfs2_del_inode_from_orphan. So move ocfs2_del_inode_from_orphan out of ip_alloc_sem to fix the deadlock. Link: https://lkml.kernel.org/r/20260306032211.1016452-1-joseph.qi@linux.alibaba.com Reported-by: syzbot+67b90111784a3eac8c04@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=67b90111784a3eac8c04 Fixes: a86a72a4a4e0 ("ocfs2: take ip_alloc_sem in ocfs2_dio_get_block & ocfs2_dio_end_io_write") Signed-off-by: Joseph Qi Reviewed-by: Heming Zhao Cc: Mark Fasheh Cc: Joel Becker Cc: Junxiao Bi Cc: Joseph Qi Cc: Changwei Ge Cc: Jun Piao Cc: Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman --- fs/ocfs2/aops.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) --- a/fs/ocfs2/aops.c +++ b/fs/ocfs2/aops.c @@ -2295,8 +2295,6 @@ static int ocfs2_dio_end_io_write(struct goto out; } - down_write(&oi->ip_alloc_sem); - /* Delete orphan before acquire i_rwsem. */ if (dwc->dw_orphaned) { BUG_ON(dwc->dw_writer_pid != task_pid_nr(current)); @@ -2309,6 +2307,7 @@ static int ocfs2_dio_end_io_write(struct mlog_errno(ret); } + down_write(&oi->ip_alloc_sem); di = (struct ocfs2_dinode *)di_bh->b_data; ocfs2_init_dinode_extent_tree(&et, INODE_CACHE(inode), di_bh);