CVE-2026-23211

A flaw was found in the Linux kernel's memory management swap subsystem. A previous commit marked the swap address space as read-only, but when arch_prepare_to_swap() fails under heavy memory pressure, the kernel attempts to set a writeback error on the read-only mapping. This triggers a kernel panic during memory reclaim operations in the page fault handler path.

This issue can occur on systems under heavy memory pressure when swap operations fail and the kernel attempts to record the error. The panic occurs in the memory reclaim path, making it potentially triggerable by any workload that causes significant memory pressure. The fix restores the swap address space to read-write to allow error reporting.

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.