CVE-2022-50165

In the Linux kernel, the following vulnerability has been resolved:

wifi: wil6210: debugfs: fix uninitialized variable use in wil_write_file_wmi()

Commit 7a4836560a61 changes simple_write_to_buffer() with memdup_user() but it forgets to change the value to be returned that came from simple_write_to_buffer() call. It results in the following warning:

warning: variable 'rc' is uninitialized when used here [-Wuninitialized] return rc; ^~

Remove rc variable and just return the passed in length if the memdup_user() succeeds.

This patch fixes an uninitialized return value in the wil_write_file_wmi() debugfs handler, which could lead to unpredictable behavior or kernel warnings when accessed. The issue was introduced in a prior refactor replacing simple_write_to_buffer() with memdup_user() but without updating the return logic. Only privileged users (typically root) can access debugfs interfaces, which justifies the high privilege requirement (PR:H) for triggering this issue.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.