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
OS | Version | Architecture | Package | Version | Filename |
---|---|---|---|---|---|
Debian | 12 | all | linux | < 5.10.46-1 | linux_5.10.46-1_all.deb |
Debian | 11 | all | linux | < 5.10.46-1 | linux_5.10.46-1_all.deb |
Debian | 10 | all | linux | < 4.19.208-1 | linux_4.19.208-1_all.deb |
Debian | 999 | all | linux | < 5.10.46-1 | linux_5.10.46-1_all.deb |
Debian | 13 | all | linux | < 5.10.46-1 | linux_5.10.46-1_all.deb |