Executive brief
The Linux kernel's DAMON memory tier sample module can be triggered to emit a kernel warning and potentially cause a denial of service if address range parameters are not properly initialized before the module is enabled. An attacker with root access could trigger this condition through sysfs, causing system instability or crashes.
Technical details
The vulnerability is a missing input validation issue in the Linux kernel's DAMON (Data Access MONitoring) mtier sample module. The damon_region structure requires non-zero positive size address ranges, but the mtier module can call damon_new_region() with invalid parameters if node{0,1}_{start,end}_addr parameters are uninitialized or if detect_node_addresses is enabled for memoryless NUMA nodes. This triggers a WARN_ONCE() in damon_new_region() and can lead to kernel warnings or instability. The fix involves validating address range parameters early in damon_sample_mtier_build_ctx() before calling damon_new_region(), allowing the module to fail gracefully rather than generate warnings.
Affected products
- Linux Linux kernel affected versions unspecified
Timeline
- 2026-08-28: disclosed