linux-kernel - Re: [PATCH] ext4: fix WARNING in lock_two

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]

Date: Mon, 25 Dec 2023 02:07:54 +0000
From: Al Viro <viro@...iv.linux.org.uk>
To: Baokun Li <libaokun1@...wei.com>
Cc: Edward Adam Davis <eadavis@...com>,
	syzbot+2c4a3b922a860084cc7f@...kaller.appspotmail.com,
	adilger.kernel@...ger.ca, linux-ext4@...r.kernel.org,
	linux-fsdevel@...r.kernel.org, linux-kernel@...r.kernel.org,
	syzkaller-bugs@...glegroups.com, tytso@....edu,
	yangerkun <yangerkun@...wei.com>
Subject: Re: [PATCH] ext4: fix WARNING in lock_two_nondirectories

On Mon, Dec 25, 2023 at 09:38:51AM +0800, Baokun Li wrote:

> In my opinion, it doesn't make sense to call lock_two_nondirectories()
> here to determine if the inode is a regular file or not, since the logic
> for dealing with non-regular files comes after the locking, so calling
> lock_two_inodes() directly here will suffice.

No.  First of all, lock_two_inodes() is a mistake that is going to be
removed in the coming cycle.

What's more, why the hell do you need to lock *anything* to check the
inode type?  Inode type never changes, period.

Just take that check prior to lock_two_nondirectories() and be done with
that.