CVEvulnerability
CVE-2026-99158
- Status
- Received
- Published
- 2026-10-28
- Last modified
- 2026-10-28
- Assigner
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Description
In the Linux kernel, the following vulnerability has been resolved:
ring-buffer: Fix false warning in ring_buffer_map_get_reader()
The mmap reader can warn when it catches up with a writer that is still
committing events. rb_get_reader_page() returns NULL in this case, but
ring_buffer_map_get_reader() treats that result as an error.
The initial rb_per_cpu_empty() check filters out an empty buffer, but it
does not guarantee that the next reader page has committed data. Writers
do not take reader_lock and can advance commit_page before publishing the
committed length on the new page. rb_get_reader_page() can swap to that
page, catch up with the writer and return NULL.
Handle NULL through the existing no-data exit without warning. Remove the
caller's reader_page == commit_page check as well, since the reader-page
helper already handles that case. The existing metadata update and return
path remain in place.