{"id":"CVE-2026-99158","title":"ring-buffer: Fix false warning in ring_buffer_map_get_reader()","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nring-buffer: Fix false warning in ring_buffer_map_get_reader()\n\nThe mmap reader can warn when it catches up with a writer that is still\ncommitting events. rb_get_reader…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= 117c39200d9d760cbd5944bb89efb7b9c51965aa < 029770f5badedc0f0ff85fc45e24785cbbee4a67","Linux >= 117c39200d9d760cbd5944bb89efb7b9c51965aa < 68e6ab180cfb6dfa79652f41ed7899a6d4cf5438","Linux >= 117c39200d9d760cbd5944bb89efb7b9c51965aa < 89bab1dba8a0167ef0d819e0f55b6bafa038e87f","Linux 6.10"],"published":"2026-10-28","updated":"2026-10-28","sourceUpdated":"2026-10-28T10:35:11.848Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-99158","references":[{"url":"https://git.kernel.org/stable/c/029770f5badedc0f0ff85fc45e24785cbbee4a67"},{"url":"https://git.kernel.org/stable/c/68e6ab180cfb6dfa79652f41ed7899a6d4cf5438"},{"url":"https://git.kernel.org/stable/c/89bab1dba8a0167ef0d819e0f55b6bafa038e87f"}],"tags":["cve.org"],"ingestedAt":"2026-10-28T11:09:40.397Z","slug":"CVE-2026-99158","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nring-buffer: Fix false warning in ring_buffer_map_get_reader()\n\nThe mmap reader can warn when it catches up with a writer that is still\ncommitting events. rb_get_reader_page() returns NULL in this case, but\nring_buffer_map_get_reader() treats that result as an error.\n\nThe initial rb_per_cpu_empty() check filters out an empty buffer, but it\ndoes not guarantee that the next reader page has committed data. Writers\ndo not take reader_lock and can advance commit_page before publishing the\ncommitted length on the new page. rb_get_reader_page() can swap to that\npage, catch up with the writer and return NULL.\n\nHandle NULL through the existing no-data exit without warning. Remove the\ncaller's reader_page == commit_page check as well, since the reader-page\nhelper already handles that case. The existing metadata update and return\npath remain in place.\n\n## Affected\n\n- `Linux >= 117c39200d9d760cbd5944bb89efb7b9c51965aa < 029770f5badedc0f0ff85fc45e24785cbbee4a67`\n- `Linux >= 117c39200d9d760cbd5944bb89efb7b9c51965aa < 68e6ab180cfb6dfa79652f41ed7899a6d4cf5438`\n- `Linux >= 117c39200d9d760cbd5944bb89efb7b9c51965aa < 89bab1dba8a0167ef0d819e0f55b6bafa038e87f`\n- `Linux 6.10`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}