On Thu, Apr 1, 2021 at 3:30 PM Alan Stern stern@rowland.harvard.edu wrote:

On Wed, Mar 31, 2021 at 02:03:08PM -0700, syzbot wrote:

...

syzbot has bisected this issue to:

commit 416dacb819f59180e4d86a5550052033ebb6d72c Author: Alan Stern stern@rowland.harvard.edu Date: Wed Aug 21 17:27:12 2019 +0000

HID: hidraw: Fix invalid read in hidraw_ioctl

bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=127430fcd00000 start commit: 6e5a03bc ethernet/netronome/nfp: Fix a use after free in n.. git tree: net final oops: https://syzkaller.appspot.com/x/report.txt?x=117430fcd00000 console output: https://syzkaller.appspot.com/x/log.txt?x=167430fcd00000 kernel config: https://syzkaller.appspot.com/x/.config?x=daeff30c2474a60f dashboard link: https://syzkaller.appspot.com/bug?extid=fbf4fc11a819824e027b syz repro: https://syzkaller.appspot.com/x/repro.syz?x=13bfe45ed00000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1188e31ad00000

Reported-by: syzbot+fbf4fc11a819824e027b@syzkaller.appspotmail.com Fixes: 416dacb819f5 ("HID: hidraw: Fix invalid read in hidraw_ioctl")

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

It seems likely that the bisection ran off the rails here. This commit could not have caused a problem, although it may have revealed a pre-existing problem that previously was hidden.

Hi Alan,

Yes, bisection log shows it was derailed by: KASAN: use-after-free Read in batadv_iv_ogm_queue_add and: BUG: MAX_LOCKDEP_CHAIN_HLOCKS too low!

https://syzkaller.appspot.com/x/bisect.txt?x=127430fcd00000

By the way, what happened to the annotated stack dumps that syzkaller used to provide in its bug reports?

Nothing has changed in this respect, they are still in bug reports: https://lore.kernel.org/lkml/00000000000073afff05bbe9a54d@google.com/