9cc45d8200
commit 0ed08faded1da03eb3def61502b27f81aef2e615 upstream. The syzbot fuzzer discovered a bad race between in the usbhid driver between usbhid_stop() and usbhid_close(). In particular, usbhid_stop() does: usb_free_urb(usbhid->urbin); ... usbhid->urbin = NULL; /* don't mess up next start */ and usbhid_close() does: usb_kill_urb(usbhid->urbin); with no mutual exclusion. If the two routines happen to run concurrently so that usb_kill_urb() is called in between the usb_free_urb() and the NULL assignment, it will access the deallocated urb structure -- a use-after-free bug. This patch adds a mutex to the usbhid private structure and uses it to enforce mutual exclusion of the usbhid_start(), usbhid_stop(), usbhid_open() and usbhid_close() callbacks. Reported-and-tested-by: syzbot+7bf5a7b0f0a1f9446f4c@syzkaller.appspotmail.com Signed-off-by: Alan Stern <stern@rowland.harvard.edu> CC: <stable@vger.kernel.org> Signed-off-by: Jiri Kosina <jkosina@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
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| .. | ||
| Kconfig | ||
| Makefile | ||
| hid-core.c | ||
| hid-pidff.c | ||
| hiddev.c | ||
| usbhid.h | ||
| usbkbd.c | ||
| usbmouse.c | ||