CVE-2025-68186

Summary

In the Linux kernel, the following vulnerability has been resolved:

ring-buffer: Do not warn in ring_buffer_map_get_reader() when reader catches up

The function ring_buffer_map_get_reader() is a bit more strict than the other get reader functions, and except for certain situations the rb_get_reader_page() should not return NULL. If it does, it triggers a warning.

This warning was triggering but after looking at why, it was because another acceptable situation was happening and it wasn't checked for.

If the reader catches up to the writer and there's still data to be read on the reader page, then the rb_get_reader_page() will return NULL as there's no new page to get.

In this situation, the reader page should not be updated and no warning should trigger.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux117c39200d9d760cbd5944bb89efb7b9c51965aa < b42dbef4f208326271434d5ab71c4129a3ddd1a9affected
LinuxLinux117c39200d9d760cbd5944bb89efb7b9c51965aa < 6f5c4f8109fa4d0955b3712597a26b310bdc736faffected
LinuxLinux117c39200d9d760cbd5944bb89efb7b9c51965aa < aa997d2d2a0b2e76f4df0f1f12829f02acb4fb6baffected
LinuxLinux6.10affected
LinuxLinux0 < 6.10unaffected
LinuxLinux6.12.58 <= 6.12.*unaffected
LinuxLinux6.17.8 <= 6.17.*unaffected
LinuxLinux6.18 <= *unaffected

Weaknesses

References