Re: KASAN: slab-out-of-bounds Read in hidraw_ioctl

From: Andrey Konovalov
Date: Wed Aug 21 2019 - 12:50:41 EST


On Wed, Aug 21, 2019 at 6:26 PM Andrey Konovalov <andreyknvl@xxxxxxxxxx> wrote:
>
> On Wed, Aug 21, 2019 at 6:24 PM Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> wrote:
> >
> > On Wed, 21 Aug 2019, Andrey Konovalov wrote:
> >
> > > On Wed, Aug 21, 2019 at 3:37 PM syzbot
> > > <syzbot+5a6c4ec678a0c6ee84ba@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote:
> > > >
> > > > Hello,
> > > >
> > > > syzbot has tested the proposed patch but the reproducer still triggered
> > > > crash:
> > > > KASAN: slab-out-of-bounds Read in hidraw_ioctl
> > >
> > > Same here, a different bug.
> >
> > It looks like I've got the fix for both these bugs. Testing now...
>
> Great! Do you think "BUG: bad usercopy in hidraw_ioctl" can also be
> fixed by one of those fixes?

We actually have a bunch of other non reproducible bug reports that
come from HID. I think I'll dup them into these two bugs that you've
fixed, and we'll see if syzkaller triggers them again once the fixes
are upstream.

>
> >
> > > > Tested on:
> > > >
> > > > commit: e96407b4 usb-fuzzer: main usb gadget fuzzer driver
> > > > git tree: https://github.com/google/kasan.git
> > > > console output: https://syzkaller.appspot.com/x/log.txt?x=14f14a1e600000
> > > > kernel config: https://syzkaller.appspot.com/x/.config?x=cfa2c18fb6a8068e
> > > > compiler: gcc (GCC) 9.0.0 20181231 (experimental)
> > > > patch: https://syzkaller.appspot.com/x/patch.diff?x=171cd95a600000
> >
> > Why don't these patch-test reports include the dashboard link? It sure
> > would be handy to have a copy of it here.

Sorry, didn't notice this comment. This should be easy to implement,
I'll look into that, thanks!