CVE-2021-47231
can: mcba_usb: fix memory leak in mcba_usb
Severity Score
Exploit Likelihood
Affected Versions
Public Exploits
0Exploited in Wild
-Decision
Descriptions
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
En el kernel de Linux, se resolvió la siguiente vulnerabilidad: can: mcba_usb: repara la pérdida de memoria en mcba_usb. Syzbot informó una pérdida de memoria en el controlador SocketCAN para la herramienta Microchip CAN BUS Analyzer. El problema estaba en usb_coherent no liberado. En mcba_usb_start() se asignan 20 buffers coherentes y no hay nada que los libere: 1) En la función de devolución de llamada, la urb se vuelve a enviar y eso es todo 2) En la función de desconexión, las urbs simplemente se eliminan, pero URB_FREE_BUFFER no está configurado (ver mcba_usb_start) y Esta bandera no se puede utilizar con buffers coherentes. Registro de errores: | [ 1354.053291][ T8413] mcba_usb 1-1:0.0 can0: dispositivo desconectado | [ 1367.059384][ T8420] kmemleak: 20 nuevas pérdidas de memoria sospechosas (ver /sys/kernel/debug/kmem) Por lo tanto, todos los buffers asignados deben liberarse con usb_free_coherent() explícitamente NOTA: Se utiliza el mismo patrón para asignar y liberar buffers coherentes en controladores/net/can/usb/kvaser_usb/kvaser_usb_core.c
CVSS Scores
SSVC
- Decision:Track
Timeline
- 2024-04-10 CVE Reserved
- 2024-05-21 CVE Published
- 2024-05-22 EPSS Updated
- 2024-08-15 CVE Updated
- ---------- Exploited in Wild
- ---------- KEV Due Date
- ---------- First Exploit
CWE
CAPEC
References (7)
| URL | Tag | Source |
|---|---|---|
| https://git.kernel.org/stable/c/51f3baad7de943780ce0c17bd7975df567dd6e14 | Vuln. Introduced |
| URL | Date | SRC |
|---|
| URL | Date | SRC |
|---|
Affected Vendors, Products, and Versions
| Vendor | Product | Version | Other | Status | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Vendor | Product | Version | Other | Status | <-- --> | Vendor | Product | Version | Other | Status |
| Linux Search vendor "Linux" | Linux Kernel Search vendor "Linux" for product "Linux Kernel" | >= 4.12 < 4.14.238 Search vendor "Linux" for product "Linux Kernel" and version " >= 4.12 < 4.14.238" | en |
Affected
| ||||||
| Linux Search vendor "Linux" | Linux Kernel Search vendor "Linux" for product "Linux Kernel" | >= 4.12 < 4.19.196 Search vendor "Linux" for product "Linux Kernel" and version " >= 4.12 < 4.19.196" | en |
Affected
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| Linux Search vendor "Linux" | Linux Kernel Search vendor "Linux" for product "Linux Kernel" | >= 4.12 < 5.4.128 Search vendor "Linux" for product "Linux Kernel" and version " >= 4.12 < 5.4.128" | en |
Affected
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| Linux Search vendor "Linux" | Linux Kernel Search vendor "Linux" for product "Linux Kernel" | >= 4.12 < 5.10.46 Search vendor "Linux" for product "Linux Kernel" and version " >= 4.12 < 5.10.46" | en |
Affected
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| Linux Search vendor "Linux" | Linux Kernel Search vendor "Linux" for product "Linux Kernel" | >= 4.12 < 5.12.13 Search vendor "Linux" for product "Linux Kernel" and version " >= 4.12 < 5.12.13" | en |
Affected
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| Linux Search vendor "Linux" | Linux Kernel Search vendor "Linux" for product "Linux Kernel" | >= 4.12 < 5.13 Search vendor "Linux" for product "Linux Kernel" and version " >= 4.12 < 5.13" | en |
Affected
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