Hi Daniel,
On 2/8/22 15:30, Daniel Vetter wrote:
On Mon, Feb 07, 2022 at 11:51:29PM -0800, syzbot wrote:
syzbot has found a reproducer for the following issue on:
HEAD commit: 555f3d7be91a Merge tag '5.17-rc3-ksmbd-server-fixes' of gi.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=130a0c2c700000
(*)
kernel config: https://syzkaller.appspot.com/x/.config?x=266de9da75c71a45 dashboard link: https://syzkaller.appspot.com/bug?extid=60df062e1c41940cae0f compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=15880d84700000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=14de0c77b00000
IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+60df062e1c41940cae0f@syzkaller.appspotmail.com
From a quick grep usb seems to have indeed gained some component code, and I'm not aware of any drm usb drivers using component. So I think this is an usb issue, not a drm one.
It looks like missing error handling. syzbot injected allocation failure inside component_add(), but usb_hub_create_port_device() just prints warn message in case of component_add() failure (see log (*))
And then calling component_del() on non-added item causes WARN_ON()
Can't prove my thoughts, since there is no repro :(
With regards, Pavel Skripkin