On Wed, 8 Jan 2020, syzbot wrote: > Hello, > > syzbot has tested the proposed patch and the reproducer did not trigger > crash: > > Reported-and-tested-by: > syzbot+10e5f68920f13587ab12@xxxxxxxxxxxxxxxxxxxxxxxxx > > Tested on: > > commit: ecdf2214 usb: gadget: add raw-gadget interface > git tree: https://github.com/google/kasan.git > kernel config: https://syzkaller.appspot.com/x/.config?x=b06a019075333661 > dashboard link: https://syzkaller.appspot.com/bug?extid=10e5f68920f13587ab12 > compiler: gcc (GCC) 9.0.0 20181231 (experimental) > patch: https://syzkaller.appspot.com/x/patch.diff?x=1583963ee00000 > > Note: testing is done by a robot and is best-effort only. I'm at a loss for a way to track this down any farther. The difference between this patch and the previous was very small and almost entirely confined to actions that take place _after_ the bug condition has been detected. If this is indeed caused by a race, it would be nice to know that the two racing threads are doing. One of them we can see in the log output (it's calling usb_control_msg) but the other is a mystery. Alan Stern
