Re: WARNING in __proc_create

[Eric Dumazet]

On 03/09/2018 02:48 PM, Cong Wang wrote:
> On Fri, Mar 9, 2018 at 1:59 PM, syzbot
> <syzbot+0502b00edac2a0680b61@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote:
> > Hello,
> >
> > syzbot hit the following crash on net-next commit
> > 617aebe6a97efa539cc4b8a52adccd89596e6be0 (Sun Feb 4 00:25:42 2018 +0000)
> > Merge tag 'usercopy-v4.16-rc1' of
> > git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
> >
> > So far this crash happened 12 times on net-next, upstream.
> > C reproducer is attached.
> > syzkaller reproducer is attached.
> > Raw console output is attached.
> > compiler: gcc (GCC) 7.1.1 20170620
> > .config is attached.
> >
> > IMPORTANT: if you fix the bug, please add the following tag to the commit:
> > Reported-by: syzbot+0502b00edac2a0680b61@xxxxxxxxxxxxxxxxxxxxxxxxx
> > It will help syzbot understand when the bug is fixed. See footer for
> > details.
> > If you forward the report, please keep this part and the footer.
> >
> > audit: type=1400 audit(1518223777.419:7): avc:  denied  { map } for
> > pid=4159 comm="syzkaller598581" path="/root/syzkaller598581546" dev="sda1"
> > ino=16481 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023
> > tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1
> > ------------[ cut here ]------------
> > name len 0
> > WARNING: CPU: 0 PID: 4159 at fs/proc/generic.c:354 __proc_create+0x696/0x880
> > fs/proc/generic.c:354
>
> We need to reject empty names.

I sent a patch a while back, but Pablo/Florian wanted more than that 
simple fix.

We also need to filter special characters like '/'

Or maybe I am mixing with something else.