Re: Reminder: 3 open syzbot bugs in vhost subsystem

From: Eric Biggers
Date: Tue Jul 23 2019 - 23:13:58 EST


On Wed, Jul 24, 2019 at 11:05:14AM +0800, Jason Wang wrote:
> > --------------------------------------------------------------------------------
> > Title: KASAN: use-after-free Write in tlb_finish_mmu
> > Last occurred: 5 days ago
> > Reported: 4 days ago
> > Branches: Mainline
> > Dashboard link: https://syzkaller.appspot.com/bug?id=d57b94f89e48c85ef7d95acc208209ea4bdc10de
> > Original thread: https://lkml.kernel.org/lkml/00000000000045e7a1058e02458a@xxxxxxxxxx/T/#u
> >
> > This bug has a syzkaller reproducer only.
> >
> > This bug was bisected to:
> >
> > commit 7f466032dc9e5a61217f22ea34b2df932786bbfc
> > Author: Jason Wang <jasowang@xxxxxxxxxx>
> > Date: Fri May 24 08:12:18 2019 +0000
> >
> >   vhost: access vq metadata through kernel virtual address
> >
> > No one has replied to the original thread for this bug yet.
> >
> > If you fix this bug, please add the following tag to the commit:
> > Reported-by: syzbot+8267e9af795434ffadad@xxxxxxxxxxxxxxxxxxxxxxxxx
> >
> > If you send any email or patch for this bug, please reply to the original
> > thread. For the git send-email command to use, or tips on how to reply if the
> > thread isn't in your mailbox, see the "Reply instructions" at
> > https://lkml.kernel.org/r/00000000000045e7a1058e02458a@xxxxxxxxxx
> >
> > --------------------------------------------------------------------------------
> > Title: KASAN: use-after-free Read in finish_task_switch (2)
> > Last occurred: 5 days ago
> > Reported: 4 days ago
> > Branches: Mainline
> > Dashboard link: https://syzkaller.appspot.com/bug?id=9a98fcad6c8bd31f5c3afbdc6c75de9f082c0ffa
> > Original thread: https://lkml.kernel.org/lkml/000000000000490679058e0245ee@xxxxxxxxxx/T/#u
> >
> > This bug has a syzkaller reproducer only.
> >
> > This bug was bisected to:
> >
> > commit 7f466032dc9e5a61217f22ea34b2df932786bbfc
> > Author: Jason Wang <jasowang@xxxxxxxxxx>
> > Date: Fri May 24 08:12:18 2019 +0000
> >
> >   vhost: access vq metadata through kernel virtual address
> >
> > No one has replied to the original thread for this bug yet.
>
>
> Hi:
>
> We believe above two bugs are duplicated with the report "WARNING in
> __mmdrop". Can I just dup them with
>
> #syz dup "WARNING in __mmdrop"
>
> (If yes, just wonder how syzbot differ bugs, technically, several different
> bug can hit the same warning).
>

Yes, please mark them as duplicates; see https://goo.gl/tpsmEJ#status for
correct syntax. You need to send the command to the syzbot email address
specific to each bug. Easiest way is to reply to the original threads.

- Eric