Linux · Linux Kernel · CVE-2021-47055
**Name of the Vulnerable Software and Affected Versions**
Linux kernel (affected versions not specified)
**Description**
The issue concerns the requirement of write permissions for locking and badblock ioctls in the Linux kernel. Specifically, `MEMLOCK`, `MEMUNLOCK`, and `OTPLOCK` modify protection bits and thus require write permission. Depending on the hardware, `MEMLOCK` might even be write-once, for example, for SPI-NOR flashes with their WP# tied to GND. `OTPLOCK` is always write-once. `MEMSETBADBLOCK` modifies the bad block table.
**Recommendations**
At the moment, there is no information about a newer version that contains a fix for this vulnerability.