Linux · Linux Kernel · CVE-2021-47640
**Name of the Vulnerable Software and Affected Versions**
Linux kernel versions prior to 5.15.0-12267-gdebe436e77c7
**Description**
The issue is related to the powerpc/kasan component of the Linux kernel, where the shadow's page table is not updated correctly when PTE RPN SHIFT is 24 and PAGE SHIFT is 12. This causes false positives and false negatives. The problem is fixed by bringing the logic of kasan early shadow page entry to the affected area.
**Recommendations**
For Linux kernel versions prior to 5.15.0-12267-gdebe436e77c7, update to a version that includes the fix for the powerpc/kasan issue.