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

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: <20230321195742.6b46syklc34es4cx@wittgenstein>
Date:   Tue, 21 Mar 2023 20:57:42 +0100
From:   Christian Brauner <brauner@...nel.org>
To:     Mike Christie <michael.christie@...cle.com>
Cc:     syzbot <syzbot+6b27b2d2aba1c80cc13b@...kaller.appspotmail.com>,
        jasowang@...hat.com, kvm@...r.kernel.org,
        linux-kernel@...r.kernel.org, mst@...hat.com,
        netdev@...r.kernel.org, syzkaller-bugs@...glegroups.com,
        virtualization@...ts.linux-foundation.org
Subject: Re: [syzbot] [kernel?] general protection fault in vhost_task_start

On Tue, Mar 21, 2023 at 12:46:04PM -0500, Mike Christie wrote:
> On 3/21/23 12:03 PM, syzbot wrote:
> > RIP: 0010:vhost_task_start+0x22/0x40 kernel/vhost_task.c:115
> > Code: 00 00 00 00 00 0f 1f 00 f3 0f 1e fa 53 48 89 fb e8 c3 67 2c 00 48 8d 7b 70 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 75 0a 48 8b 7b 70 5b e9 fe bd 02 00 e8 79 ec 7e 00 eb
> > RSP: 0018:ffffc90003a9fc38 EFLAGS: 00010207
> > RAX: dffffc0000000000 RBX: fffffffffffffff4 RCX: 0000000000000000
> > RDX: 000000000000000c RSI: ffffffff81564c8d RDI: 0000000000000064
> > RBP: ffff88802b21dd40 R08: 0000000000000100 R09: ffffffff8c917cf3
> > R10: 00000000fffffff4 R11: 0000000000000000 R12: fffffffffffffff4
> > R13: ffff888075d000b0 R14: ffff888075d00000 R15: ffff888075d00008
> > FS:  0000555556247300(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
> > CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> > CR2: 00007ffe3d8e5ff8 CR3: 00000000215d4000 CR4: 00000000003506f0
> > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> > Call Trace:
> >  <TASK>
> >  vhost_worker_create drivers/vhost/vhost.c:580 [inline]
> 
> The return value from vhost_task_create is incorrect if the kzalloc fails.
> 
> Christian, here is a fix for what's in your tree. Do you want me to submit
> a follow up patch like this or a replacement patch for:
> 
> commit 77feab3c4156 ("vhost_task: Allow vhost layer to use copy_process")

Since this has been in linux-next my tendency is to just put this fix on
top. So please slap a Fixes: tag on it and a Link to the syzbot report.
I also tend to annotate such fixes with "# mainline only":

Fixes: 77feab3c4156 ("vhost_task: Allow vhost layer to use copy_process") # mainline only

to prevent AUTOSEL from picking this up.

Thanks for taking care of this so quickly!
Christian