CVE-2021-47560

Description

In the Linux kernel, the following vulnerability has been resolved: mlxsw: spectrum: Protect driver from buggy firmware When processing port up/down events generated by the device's firmware, the driver protects itself from events reported for non-existent local ports, but not the CPU port (local port 0), which exists, but lacks a netdev. This can result in a NULL pointer dereference when calling netif_carrier_{on,off}(). Fix this by bailing early when processing an event reported for the CPU port. Problem was only observed when running on top of a buggy emulator.

CVSS Metrics

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

EPSS Trends

Current EPSS score: 0.03%• Percentile: 8%

Techniques & Countermeasures

• CWE-476•NULL Pointer Dereference

  The product dereferences a pointer that it expects to be valid but is NULL.

Affected Systems

• linux•linux

  ≥ 28b1987ef5064dd5c43538ba1168ef7b801f3cad, < 90d0736876c50ecde1a3275636a06b9ddb1cace9 | ≥ 28b1987ef5064dd5c43538ba1168ef7b801f3cad, < da4d70199e5d82da664a80077508d6c18f5e76df | ≥ 28b1987ef5064dd5c43538ba1168ef7b801f3cad, < 63b08b1f6834bbb0b4f7783bf63b80c8c8e9a047 | 5.4

• linux•linux_kernel

  ≥ 5.4, < 5.10.83 | ≥ 5.11, < 5.15.6 | 5.16:rc1 | 5.16:rc2

References (3)

• https://git.kernel.org/stable/c/90d0736876c50ecde1a3275636a06b9ddb1cace9
• https://git.kernel.org/stable/c/da4d70199e5d82da664a80077508d6c18f5e76df
• https://git.kernel.org/stable/c/63b08b1f6834bbb0b4f7783bf63b80c8c8e9a047