linux-kernel - Re: [PATCH] ocfs2: fix lock acquisition order in refcounttree

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <5957f94d-2521-43d4-ba0b-7b98576167a4@I-love.SAKURA.ne.jp>
Date: Tue, 15 Jul 2025 11:51:17 +0900
From: Tetsuo Handa <penguin-kernel@...ove.SAKURA.ne.jp>
To: Diogo Jahchan Koike <djahchankoike@...il.com>,
        Mark Fasheh <mark@...heh.com>, Joel Becker <jlbec@...lplan.org>,
        Joseph Qi <joseph.qi@...ux.alibaba.com>
Cc: syzbot+1fed2de07d8e11a3ec1b@...kaller.appspotmail.com,
        ocfs2-devel@...ts.linux.dev, linux-kernel@...r.kernel.org
Subject: Re: [PATCH] ocfs2: fix lock acquisition order in refcounttree

On 2025/07/15 7:15, Diogo Jahchan Koike wrote:
> Acquiring the locks in refcounttree should follow
> the ip_alloc --> ip_xattr ordering, as done by multiple
> code paths in ocfs2; otherwise, we risk an ABBA deadlock
> (i.e in the start transaction path).

I noticed that ocfs2_reflink() in the same file wants similar change.

	down_write(&OCFS2_I(inode)->ip_xattr_sem);
	down_write(&OCFS2_I(inode)->ip_alloc_sem);
	error = __ocfs2_reflink(old_dentry, old_bh,
				new_orphan_inode, preserve);
	up_write(&OCFS2_I(inode)->ip_alloc_sem);
	up_write(&OCFS2_I(inode)->ip_xattr_sem);