// For flags

CVE-2021-47541

net/mlx4_en: Fix an use-after-free bug in mlx4_en_try_alloc_resources()

Severity Score

7.8
*CVSS v3.1

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:

net/mlx4_en: Fix an use-after-free bug in mlx4_en_try_alloc_resources()

In mlx4_en_try_alloc_resources(), mlx4_en_copy_priv() is called and
tmp->tx_cq will be freed on the error path of mlx4_en_copy_priv().
After that mlx4_en_alloc_resources() is called and there is a dereference
of &tmp->tx_cq[t][i] in mlx4_en_alloc_resources(), which could lead to
a use after free problem on failure of mlx4_en_copy_priv().

Fix this bug by adding a check of mlx4_en_copy_priv()

This bug was found by a static analyzer. The analysis employs
differential checking to identify inconsistent security operations
(e.g., checks or kfrees) between two code paths and confirms that the
inconsistent operations are not recovered in the current function or
the callers, so they constitute bugs.

Note that, as a bug found by static analysis, it can be a false
positive or hard to trigger. Multiple researchers have cross-reviewed
the bug.

Builds with CONFIG_MLX4_EN=m show no new warnings,
and our static analyzer no longer warns about this code.

En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: net/mlx4_en: corrige un error de use-after-free en mlx4_en_try_alloc_resources() En mlx4_en_try_alloc_resources(), se llama a mlx4_en_copy_priv() y se liberará tmp->tx_cq en la ruta del error de mlx4_en_copy_priv(). Después de eso, se llama a mlx4_en_alloc_resources() y hay una desreferencia de &tmp->tx_cq[t][i] en mlx4_en_alloc_resources(), lo que podría llevar a un problema de use-after-free si falla mlx4_en_copy_priv(). Corrija este error agregando una verificación de mlx4_en_copy_priv() Este error fue encontrado por un analizador estático. El análisis emplea verificación diferencial para identificar operaciones de seguridad inconsistentes (por ejemplo, comprobaciones o kfrees) entre dos rutas de código y confirma que las operaciones inconsistentes no se recuperan en la función actual o en las personas que llaman, por lo que constituyen errores. Tenga en cuenta que, como error encontrado mediante análisis estático, puede ser un falso positivo o difícil de activar. Varios investigadores han realizado una revisión cruzada del error. Las compilaciones con CONFIG_MLX4_EN=m no muestran nuevas advertencias y nuestro analizador estático ya no advierte sobre este código.

*Credits: N/A
CVSS Scores
Attack Vector
Local
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High
* Common Vulnerability Scoring System
SSVC
  • Decision:Track
Exploitation
None
Automatable
No
Tech. Impact
Partial
* Organization's Worst-case Scenario
Timeline
  • 2024-05-24 CVE Reserved
  • 2024-05-24 CVE Published
  • 2024-06-11 EPSS Updated
  • 2024-12-19 CVE Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
  • ---------- First Exploit
CWE
  • CWE-416: Use After Free
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"
>= 4.7 < 4.14.257
Search vendor "Linux" for product "Linux Kernel" and version " >= 4.7 < 4.14.257"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 4.7 < 4.19.220
Search vendor "Linux" for product "Linux Kernel" and version " >= 4.7 < 4.19.220"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 4.7 < 5.4.164
Search vendor "Linux" for product "Linux Kernel" and version " >= 4.7 < 5.4.164"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 4.7 < 5.10.84
Search vendor "Linux" for product "Linux Kernel" and version " >= 4.7 < 5.10.84"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 4.7 < 5.15.7
Search vendor "Linux" for product "Linux Kernel" and version " >= 4.7 < 5.15.7"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 4.7 < 5.16
Search vendor "Linux" for product "Linux Kernel" and version " >= 4.7 < 5.16"
en
Affected