linux-kernel - Re: [syzbot] [btrfs?] general protection fault in apply_wqattrs

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] [day] [month] [year] [list]

Message-ID: <20240730143452.GG17473@twin.jikos.cz>
Date: Tue, 30 Jul 2024 16:34:52 +0200
From: David Sterba <dsterba@...e.cz>
To: syzbot <syzbot+1b5f11df288ca3853de9@...kaller.appspotmail.com>
Cc: clm@...com, dsterba@...e.com, josef@...icpanda.com,
	linux-btrfs@...r.kernel.org, linux-kernel@...r.kernel.org,
	syzkaller-bugs@...glegroups.com
Subject: Re: [syzbot] [btrfs?] general protection fault in
 apply_wqattrs_cleanup

On Mon, Jun 03, 2024 at 06:56:31AM -0700, syzbot wrote:
> Hello,
> 
> syzbot found the following issue on:
> 
> HEAD commit:    c3f38fa61af7 Linux 6.10-rc2
> git tree:       upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=127bdaba980000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=998c63c06e77f5e7
> dashboard link: https://syzkaller.appspot.com/bug?extid=1b5f11df288ca3853de9
> compiler:       gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
> userspace arch: i386
> 
> Unfortunately, I don't have any reproducer for this issue yet.

Most likely this was a side effect of bug fixed by commit f3a5367c679d
("btrfs: protect folio::private when attaching extent buffer folios").

The timeframe corresponds with increased number of bogus errors caused
by use-after-free of a page. The stack trace reported by syzbot is
inside allocation, likely reusing a page.

The fix is best guess.

#syz fix: btrfs: protect folio::private when attaching extent buffer folios