Linux · Linux Kernel · CVE-2021-47080
**Name of the Vulnerable Software and Affected Versions**
Linux kernel versions prior to 5.13.0-rc1+
**Description**
A divide-by-zero error can be triggered in the Linux kernel by a user-supplied value, specifically the `user entry size`, which is used as a denominator to calculate the number of entries. When a zero value is supplied, it triggers a divide-by-zero error. The error occurs in the `ib uverbs handler UVERBS METHOD QUERY GID TABLE` function.
**Recommendations**
To resolve this issue, update the Linux kernel to a version that includes the fix for this vulnerability.
As a temporary workaround, consider restricting access to the `ib uverbs handler UVERBS METHOD QUERY GID TABLE` function until a patch is available.
Avoid using the `user entry size` parameter with a value of zero in the affected API endpoint until the issue is resolved.