CVE-2021-47050: 
Linux Kernel vulnerability analysis and mitigation

CVE-2021-47050 is a vulnerability in the Linux kernel affecting the Renesas RPC-IF driver. The issue was discovered in the memory subsystem where a NULL pointer dereference could occur in the platform_get_resource_byname() function. The vulnerability affects Linux kernel versions from 5.9 up to (excluding) 5.10.37, versions from 5.11 up to (excluding) 5.11.21, and versions from 5.12 up to (excluding) 5.12.4 (NVD).

The vulnerability stems from improper validation of a resource pointer before dereferencing. Specifically, the platform_get_resource_byname() function could return NULL, which would then be immediately dereferenced by resource_size(). The issue was identified in the drivers/memory/renesas-rpc-if.c file. The vulnerability has been assigned a CVSS v3.1 Base Score of 5.5 (Medium) with the vector string CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H (NVD).

The vulnerability could lead to a system crash due to NULL pointer dereference in the Renesas RPC-IF driver. This primarily affects the availability of the system, as indicated by the CVSS metrics showing high impact on availability but no impact on confidentiality or integrity (NVD).

The vulnerability requires local access with low complexity and low privileges to exploit. No user interaction is needed for exploitation, as indicated by the CVSS metrics (AV:L/AC:L/PR:L/UI:N) (NVD).

The vulnerability has been fixed by validating the resource pointer before dereferencing it. The fix involves moving the resource_size() call after the validation check. The patch has been committed to the Linux kernel and is available in updated versions (Kernel Patch).