Le 19/02/2024 à 14:10, syzbot a écrit :
syzbot has bisected this issue to: commit c838530d230bc638d79b78737fc4488ffc28c1ee Author: Benjamin Gaignard <benjamin.gaignard@xxxxxxxxxxxxx> Date: Thu Nov 9 16:34:59 2023 +0000 media: media videobuf2: Be more flexible on the number of queue stored buffers bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=166dc872180000 start commit: b401b621758e Linux 6.8-rc5 git tree: upstream final oops: https://syzkaller.appspot.com/x/report.txt?x=156dc872180000 console output: https://syzkaller.appspot.com/x/log.txt?x=116dc872180000 kernel config: https://syzkaller.appspot.com/x/.config?x=eff9f3183d0a20dd dashboard link: https://syzkaller.appspot.com/bug?extid=3b1d4b3d5f7a358bf9a9 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=13ffaae8180000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=13ef909c180000 Reported-by: syzbot+3b1d4b3d5f7a358bf9a9@xxxxxxxxxxxxxxxxxxxxxxxxx Fixes: c838530d230b ("media: media videobuf2: Be more flexible on the number of queue stored buffers") For information about bisection process see: https://goo.gl/tpsmEJ#bisection
Hans, I think the issue occur because of this part of the commit: @@ -1264,7 +1264,7 @@ void vb2_video_unregister_device(struct video_device *vdev) */ get_device(&vdev->dev); video_unregister_device(vdev); - if (vdev->queue && vdev->queue->owner) { + if (vdev->queue) { struct mutex *lock = vdev->queue->lock ? vdev->queue->lock : vdev->lock; but I wonder if the correction shouldn't be to remove usbtv->vb2q_lock mutex in usbtv_video_free(). Any opinion ? Regards, Benjamin