Linux Kernel Vulnerability Affecting Writeback Throttling Initialization

CVE-2026-53319

What is CVE-2026-53319?

The Linux kernel has a vulnerability in the wbt_init_enable_default() function, where it improperly handles expected failures from memory allocation and initialization processes. This function, called during disk queue registration, uses WARN_ON_ONCE to check for failures in wbt_alloc() and wbt_init(). However, these failures are anticipated results under normal operational conditions, such as memory pressure or already registered writeback throttling, which does not prevent the disk from functioning—merely operating without writeback throttling. The code has been modified to replace spurious warnings with simple if-checks and relevant warnings for diagnostic clarity without the complications of full stack traces.

References