// For flags

CVE-2021-46956

virtiofs: fix memory leak in virtio_fs_probe()

Severity Score

5.5
*CVSS v3

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

0
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

Track
*SSVC
Descriptions

In the Linux kernel, the following vulnerability has been resolved: virtiofs: fix memory leak in virtio_fs_probe() When accidentally passing twice the same tag to qemu, kmemleak ended up
reporting a memory leak in virtiofs. Also, looking at the log I saw the
following error (that's when I realised the duplicated tag): virtiofs: probe of virtio5 failed with error -17 Here's the kmemleak log for reference: unreferenced object 0xffff888103d47800 (size 1024): comm "systemd-udevd", pid 118, jiffies 4294893780 (age 18.340s) hex dump (first 32 bytes): 00 00 00 00 ad 4e ad de ff ff ff ff 00 00 00 00 .....N.......... ff ff ff ff ff ff ff ff 80 90 02 a0 ff ff ff ff ................ backtrace: [<000000000ebb87c1>] virtio_fs_probe+0x171/0x7ae [virtiofs] [<00000000f8aca419>] virtio_dev_probe+0x15f/0x210 [<000000004d6baf3c>] really_probe+0xea/0x430 [<00000000a6ceeac8>] device_driver_attach+0xa8/0xb0 [<00000000196f47a7>] __driver_attach+0x98/0x140 [<000000000b20601d>] bus_for_each_dev+0x7b/0xc0 [<00000000399c7b7f>] bus_add_driver+0x11b/0x1f0 [<0000000032b09ba7>] driver_register+0x8f/0xe0 [<00000000cdd55998>] 0xffffffffa002c013 [<000000000ea196a2>] do_one_initcall+0x64/0x2e0 [<0000000008f727ce>] do_init_module+0x5c/0x260 [<000000003cdedab6>] __do_sys_finit_module+0xb5/0x120 [<00000000ad2f48c6>] do_syscall_64+0x33/0x40 [<00000000809526b5>] entry_SYSCALL_64_after_hwframe+0x44/0xae

En el kernel de Linux se ha resuelto la siguiente vulnerabilidad: virtiofs: corrige pérdida de memoria en virtio_fs_probe() Al pasar accidentalmente dos veces la misma etiqueta a qemu, kmemleak terminó reportando una pérdida de memoria en virtiofs. Además, mirando el registro vi el siguiente error (fue entonces cuando me di cuenta de la etiqueta duplicada): virtiofs: la sonda de virtio5 falló con el error -17 Aquí está el registro kmemleak como referencia: objeto sin referencia 0xffff888103d47800 (tamaño 1024): comm "systemd- udevd", pid 118, jiffies 4294893780 (edad 18.340 s) volcado hexadecimal (primeros 32 bytes): 00 00 00 00 ad 4e ad de ff ff ff ff 00 00 00 00 ......N....... ... ff ff ff ff ff ff ff ff 80 90 02 a0 ff ff ff ff ................ rastreo: [&lt;000000000ebb87c1&gt;] virtio_fs_probe+0x171/0x7ae [virtiofs] [&lt;00000000f8aca419&gt;] virtio_dev_probe+0x15f/0x210 [&lt;000000004d6baf3c&gt;] very_probe+0xea/0x430 [&lt;00000000a6ceeac8&gt;] device_driver_attach+0xa8/0xb0 [&lt;00000000196f47a7 &gt;] __driver_attach+0x98/0x140 [&lt;000000000b20601d&gt;] bus_for_each_dev+0x7b/0xc0 [&lt;00000000399c7b7f&gt;] bus_add_driver+0x11b/0x1f0 [&lt;0000000032b09ba7&gt;] driver_register+0x8f/0xe0 [&lt;00000000cdd55998&gt;] 0xffffffffa002c013 [&lt;000000000ea196a2&gt; ] do_one_initcall+0x64/0x2e0 [&lt;0000000008f727ce&gt;] do_init_module+0x5c/0x260 [&lt;000000003cdedab6&gt; ] __do_sys_finit_module+0xb5/0x120 [&lt;00000000ad2f48c6&gt;] do_syscall_64+0x33/0x40 [&lt;00000000809526b5&gt;] Entry_SYSCALL_64_after_hwframe+0x44/0xae

In the Linux kernel, the following vulnerability has been resolved: virtiofs: fix memory leak in virtio_fs_probe() When accidentally passing twice the same tag to qemu, kmemleak ended up reporting a memory leak in virtiofs. Also, looking at the log I saw the following error (that's when I realised the duplicated tag): virtiofs: probe of virtio5 failed with error -17 Here's the kmemleak log for reference: unreferenced object 0xffff888103d47800 (size 1024): comm "systemd-udevd", pid 118, jiffies 4294893780 (age 18.340s) hex dump (first 32 bytes): 00 00 00 00 ad 4e ad de ff ff ff ff 00 00 00 00 .....N.......... ff ff ff ff ff ff ff ff 80 90 02 a0 ff ff ff ff ................ backtrace: [<000000000ebb87c1>] virtio_fs_probe+0x171/0x7ae [virtiofs] [<00000000f8aca419>] virtio_dev_probe+0x15f/0x210 [<000000004d6baf3c>] really_probe+0xea/0x430 [<00000000a6ceeac8>] device_driver_attach+0xa8/0xb0 [<00000000196f47a7>] __driver_attach+0x98/0x140 [<000000000b20601d>] bus_for_each_dev+0x7b/0xc0 [<00000000399c7b7f>] bus_add_driver+0x11b/0x1f0 [<0000000032b09ba7>] driver_register+0x8f/0xe0 [<00000000cdd55998>] 0xffffffffa002c013 [<000000000ea196a2>] do_one_initcall+0x64/0x2e0 [<0000000008f727ce>] do_init_module+0x5c/0x260 [<000000003cdedab6>] __do_sys_finit_module+0xb5/0x120 [<00000000ad2f48c6>] do_syscall_64+0x33/0x40 [<00000000809526b5>] entry_SYSCALL_64_after_hwframe+0x44/0xae

*Credits: N/A
CVSS Scores
Attack Vector
Local
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High
Attack Vector
Local
Attack Complexity
Low
Authentication
None
Confidentiality
None
Integrity
None
Availability
Complete
* Common Vulnerability Scoring System
SSVC
  • Decision:Track
Exploitation
None
Automatable
No
Tech. Impact
Partial
* Organization's Worst-case Scenario
Timeline
  • 2024-02-27 CVE Reserved
  • 2024-02-27 CVE Published
  • 2024-12-17 EPSS Updated
  • 2024-12-19 CVE Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
  • ---------- First Exploit
CWE
CAPEC
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"
>= 5.4 < 5.4.118
Search vendor "Linux" for product "Linux Kernel" and version " >= 5.4 < 5.4.118"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 5.4 < 5.10.36
Search vendor "Linux" for product "Linux Kernel" and version " >= 5.4 < 5.10.36"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 5.4 < 5.11.20
Search vendor "Linux" for product "Linux Kernel" and version " >= 5.4 < 5.11.20"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 5.4 < 5.12.3
Search vendor "Linux" for product "Linux Kernel" and version " >= 5.4 < 5.12.3"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 5.4 < 5.13
Search vendor "Linux" for product "Linux Kernel" and version " >= 5.4 < 5.13"
en
Affected