Unscored severity · published Oct 28, 2026
CVE-2026-99158
ring-buffer: Fix false warning in ring_buffer_map_get_reader()
New
–
CVSS
–
EPSS
No
On KEV
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.
Exploitation
Is it being used?
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
LI
Linux · Linux
117c39200d9d760cbd5944bb89efb7b9c51965aa before 029770f5badedc0f0ff85fc45e24785cbbee4a67; 117c39200d9d760cbd5944bb89efb7b9c51965aa before 68e6ab180cfb6dfa79652f41ed7899a6d4cf5438; 117c39200d9d760cbd5944bb89efb7b9c51965aa before 89bab1dba8a0167ef0d819e0f55b6bafa038e87f; 6.10 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-99158
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-99158
git.kernel.org
https://git.kernel.org/stable/c/029770f5badedc0f0ff85fc45e24785cbbee4a67
git.kernel.org
https://git.kernel.org/stable/c/68e6ab180cfb6dfa79652f41ed7899a6d4cf5438
git.kernel.org
https://git.kernel.org/stable/c/89bab1dba8a0167ef0d819e0f55b6bafa038e87f
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