CVE Published: 21/05/2024 |
CVE Updated: 06/11/2024 |
CVE Year: 2021 Source: Linux |
Vendor: Linux |
Product: Linux Status : PUBLISHED
CVE-2021-47231 Description
In the Linux kernel, the following vulnerability has been resolved:
can: mcba_usb: fix memory leak in mcba_usb
Syzbot reported memory leak in SocketCAN driver for Microchip CAN BUS
Analyzer Tool. The problem was in unfreed usb_coherent.
In mcba_usb_start() 20 coherent buffers are allocated and there is
nothing, that frees them:
1) In callback function the urb is resubmitted and that\'s all
2) In disconnect function urbs are simply killed, but URB_FREE_BUFFER
is not set (see mcba_usb_start) and this flag cannot be used with
coherent buffers.
Fail log:
| [ 1354.053291][ T8413] mcba_usb 1-1:0.0 can0: device disconnected
| [ 1367.059384][ T8420] kmemleak: 20 new suspected memory leaks (see /sys/kernel/debug/kmem)
So, all allocated buffers should be freed with usb_free_coherent()
explicitly
NOTE:
The same pattern for allocating and freeing coherent buffers
is used in drivers/net/can/usb/kvaser_usb/kvaser_usb_core.c