In the Linux kernel, the following vulnerability has been resolved:
media: streamzap: fix race between device disconnection and urb callback
Syzkaller has reported a general protection fault at function ir_raw_event_store_with_filter(). This crash is caused by a NULL pointer dereference of dev->raw pointer, even though it is checked for NULL in the same function, which means there is a race condition. It occurs due to the incorrect order of actions in the streamzap_disconnect() function: rc_unregister_device() is called before usb_kill_urb(). The dev->raw pointer is freed and set to NULL in rc_unregister_device(), and only after that usb_kill_urb() waits for in-progress requests to finish.
If rc_unregister_device() is called while streamzap_callback() handler is not finished, this can lead to accessing freed resources. Thus rc_unregister_device() should be called after usb_kill_urb().
Found by Linux Verification Center (linuxtesting.org) with Syzkaller.
Exploitability
AV:LAC:HPR:LUI:NScope
S:UImpact
C:NI:NA:H4.7/CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H