CVE-2021-47231

published 2024-05-21

CVE-2021-47231: 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…

Priority P4 18 medium 5.5 CVSS 3.1

AV L AC L PR L UI N S U C N I N A H

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

Affected

18 ranges

Vendor	Product	Version range	Fixed in
debian	linux	< linux 5.10.46-1 (bookworm)	linux 5.10.46-1 (bookworm)
linux	linux	—	—
linux	linux	>= 51f3baad7de943780ce0c17bd7975df567dd6e14 < 89df95ce32be204eef2e7d4b2f6fb552fb191a68	89df95ce32be204eef2e7d4b2f6fb552fb191a68
linux	linux	>= 51f3baad7de943780ce0c17bd7975df567dd6e14 < a115198caaab6d663bef75823a3c5f0802306d60	a115198caaab6d663bef75823a3c5f0802306d60
linux	linux	>= 51f3baad7de943780ce0c17bd7975df567dd6e14 < 6f87c0e21ad20dd3d22108e33db1c552dfa352a0	6f87c0e21ad20dd3d22108e33db1c552dfa352a0
linux	linux	>= 51f3baad7de943780ce0c17bd7975df567dd6e14 < 6bd3d80d1f019cefa7011056c54b323f1d8b8e83	6bd3d80d1f019cefa7011056c54b323f1d8b8e83
linux	linux	>= 51f3baad7de943780ce0c17bd7975df567dd6e14 < d0760a4ef85697bc756d06eae17ae27f3f055401	d0760a4ef85697bc756d06eae17ae27f3f055401
linux	linux	>= 51f3baad7de943780ce0c17bd7975df567dd6e14 < 91c02557174be7f72e46ed7311e3bea1939840b0	91c02557174be7f72e46ed7311e3bea1939840b0
linux	linux_kernel	—	—
linux	linux_kernel	>= 0 < 5.10.46-1	5.10.46-1
linux	linux_kernel	>= 0 < 5.10.46-1	5.10.46-1
linux	linux_kernel	>= 0 < 5.10.46-1	5.10.46-1
linux	linux_kernel	>= 0 < 5.10.46-1	5.10.46-1
linux	linux_kernel	>= 4.12 < 4.14.238	4.14.238
linux	linux_kernel	>= 4.15 < 4.19.196	4.19.196
linux	linux_kernel	>= 4.20 < 5.4.128	5.4.128
linux	linux_kernel	>= 5.11 < 5.12.13	5.12.13
linux	linux_kernel	>= 5.5 < 5.10.46	5.10.46

CVSS provenance

nvd v3.1 5.5 MEDIUM CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

osv 5.5 MEDIUM

vendor_debian 5.5 MEDIUM

vendor_redhat 5.5 MEDIUM

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