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 5B04E33F586 for ; Mon, 20 Apr 2026 14:58:37 +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=1776697117; cv=none; b=CAHyogsusaq6WqtDsDXU0jDkZzzS5ZXgiHJ80ZLbDkVfpei8vWrK1iCOQiTJdvvdpI3N5NJMde9XVPbJz0ccunEGXZ+zNRKVNJkkI6Co1RTPcEWM6OfJaWloYBvOUxa1f8ttx8SO6jZ+LfmsbFnRzJMgMikMBTIwm4+Ulygmbdw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776697117; c=relaxed/simple; bh=+Wd/PnzeY4J25LXViXz38e+GUx4SIRTdF832PGNKIeU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Te0aMdwrlkUdm+Bed4Lc20f70VgA24zZmPOkaAaN7D+fvQp8mimhku74c7ROLHxY3qu9OQzxHO0DxG6Tm8zGLkfrZZpv0JggHpuFw/LnWZLmPJ76eVGBgN2YNomO4HuIqyL/Eew4wkjPjj+Sg1XxXgkraXUPh1wOYe20apIQ3l8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=LFSkAcUS; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="LFSkAcUS" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 17DF5C2BCB6; Mon, 20 Apr 2026 14:58:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1776697117; bh=+Wd/PnzeY4J25LXViXz38e+GUx4SIRTdF832PGNKIeU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=LFSkAcUSSs1bHEPRHUPQfsztSLRDYfCGG9Yq4tKvDbpbzmCMbTx0UrdyAmNaKBDKY Xh2jshEwhEmeIwCzra3gQ8WwS0+7/IMNR+7RXj64sFgkNQow8Z7P1ZlGiIt24Wd/X8 utzSYYjtoNvIjulY2yKAXVF+aV4rw8F8c9Ik53EIJRHVMMtBPatQql2TsyoDA48FyD mMHDHpxX2JmcDo6pGqjaoSDFmBvGIIc9jOuMmFXfdKe96nRUNlZWv8UKE4Zh14tDqV OzW9VN6l1U4I0PTBiUp+wLYrE9H+s30sItJ/qhOBMJZYVCtNh2JRc4M53ZLP0nr+Ss ZeF9oHflMfCXg== From: Sasha Levin To: stable@vger.kernel.org Cc: Joseph Qi , syzbot+67b90111784a3eac8c04@syzkaller.appspotmail.com, Heming Zhao , Mark Fasheh , Joel Becker , Junxiao Bi , Joseph Qi , Changwei Ge , Jun Piao , Andrew Morton , Sasha Levin Subject: [PATCH 5.10.y 2/2] ocfs2: fix possible deadlock between unlink and dio_end_io_write Date: Mon, 20 Apr 2026 10:58:33 -0400 Message-ID: <20260420145833.1151197-2-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260420145833.1151197-1-sashal@kernel.org> References: <2026042003-rocking-engine-1cb6@gregkh> <20260420145833.1151197-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Joseph Qi [ Upstream commit b02da26a992db0c0e2559acbda0fc48d4a2fd337 ] 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: Sasha Levin --- fs/ocfs2/aops.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c index c4a47ea14b5fe..37aafa223c052 100644 --- a/fs/ocfs2/aops.c +++ b/fs/ocfs2/aops.c @@ -2325,8 +2325,6 @@ static int ocfs2_dio_end_io_write(struct inode *inode, 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)); @@ -2339,6 +2337,7 @@ static int ocfs2_dio_end_io_write(struct inode *inode, 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); -- 2.53.0