Re: KASAN: slab-out-of-bounds Write in validate_chain

Re: KASAN: slab-out-of-bounds Write in validate_chain

[syzbot]

syzbot has bisected this bug to:

commit e9db4ef6bf4ca9894bb324c76e01b8f1a16b2650
Author: John Fastabend <john.fastabend@gmail.com>
Date:   Sat Jun 30 13:17:47 2018 +0000

     bpf: sockhash fix omitted bucket lock in sock_close

bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=14a4e9b5a00000
start commit:   abf02e29 Merge tag 'pm-5.2-rc6' of git://git.kernel.org/pu..
git tree:       upstream
final crash:    https://syzkaller.appspot.com/x/report.txt?x=16a4e9b5a00000
console output: https://syzkaller.appspot.com/x/log.txt?x=12a4e9b5a00000
kernel config:  https://syzkaller.appspot.com/x/.config?x=28ec3437a5394ee0
dashboard link: https://syzkaller.appspot.com/bug?extid=8893700724999566d6a9
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=167098b2a00000

Reported-by: syzbot+8893700724999566d6a9@syzkaller.appspotmail.com
Fixes: e9db4ef6bf4c ("bpf: sockhash fix omitted bucket lock in sock_close")

For information about bisection process see: https://goo.gl/tpsmEJ#bisection

Re: KASAN: slab-out-of-bounds Write in validate_chain

[Eric Biggers]

Hi John,

On Tue, Jun 25, 2019 at 04:07:00PM -0700, syzbot wrote:
> syzbot has bisected this bug to:
> 
> commit e9db4ef6bf4ca9894bb324c76e01b8f1a16b2650
> Author: John Fastabend <john.fastabend@gmail.com>
> Date:   Sat Jun 30 13:17:47 2018 +0000
> 
>     bpf: sockhash fix omitted bucket lock in sock_close
> 

Are you working on this?  This is the 6th open syzbot report that has been
bisected to this commit, and I suspect it's the cause of many of the other
30 open syzbot reports I assigned to the bpf subsystem too
(https://lore.kernel.org/bpf/20190624050114.GA30702@sol.localdomain/).

Also, this is happening in mainline (v5.2-rc6).

- Eric

Re: KASAN: slab-out-of-bounds Write in validate_chain

[John Fastabend]

Eric Biggers wrote:
> Hi John,
> 
> On Tue, Jun 25, 2019 at 04:07:00PM -0700, syzbot wrote:
> > syzbot has bisected this bug to:
> > 
> > commit e9db4ef6bf4ca9894bb324c76e01b8f1a16b2650
> > Author: John Fastabend <john.fastabend@gmail.com>
> > Date:   Sat Jun 30 13:17:47 2018 +0000
> > 
> >     bpf: sockhash fix omitted bucket lock in sock_close
> > 
> 
> Are you working on this?  This is the 6th open syzbot report that has been
> bisected to this commit, and I suspect it's the cause of many of the other
> 30 open syzbot reports I assigned to the bpf subsystem too
> (https://lore.kernel.org/bpf/20190624050114.GA30702@sol.localdomain/).
> 
> Also, this is happening in mainline (v5.2-rc6).
> 
> - Eric

Should have a fix today. It seems syzbot has found this bug repeatedly.

.John