CVEvulnerability

CVE-2021-47231

5.5 MEDIUM Published 2024-05-21 Modified 2026-06-17 Official page ↗
Status
Analyzed
Published
2024-05-21
Last modified
2026-06-17
Assigner
416baaa9-dc9f-4396-8d5f-8c081fb06d67
CVSS 3.1 (134c704f-9b21-4f2e-91b3-4a467353bcc0)
5.5 MEDIUM — CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Weaknesses
CWE-401

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

Affected configurations

• linux linux kernel (>= 4.12 < 4.14.238) • linux linux kernel (>= 4.15 < 4.19.196) • linux linux kernel (>= 4.20 < 5.4.128) • linux linux kernel (>= 5.5 < 5.10.46) • linux linux kernel (>= 5.11 < 5.12.13) • linux linux kernel 5.13

Related

Weakness · CWE (1)

  • CWE-401 Missing Release of Memory after Effective Lifetime weakness

References