{"id":"CVE-2026-89500","summary":"ring-buffer: Make cpu_buffer::free_page a buffer_data_read_page","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nring-buffer: Make cpu_buffer::free_page a buffer_data_read_page\n\nDiscarding a cached reader page after a concurrent ring buffer resize\nuses the new global subbuf_order for the free_pages() call. This\nmismatched order may crashes the kernel or leaks memory because the cached\npage was allocated under the old size.\n\nSave the actual free_page order alongside the page address to ensure we\nalways refer to the correct value and do not rely on the potentially\nstalled cpu_buffer-\u003esubbuf_order value. The simplest is to make\nfree_page a buffer_data_read_page which already covers exactly what we\nneed: a page address and a page order.","modified":"2026-09-13T03:47:18.732110091Z","published":"2026-09-11T19:43:49.392Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89500.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/7a1fb95de5404134f8758c1295ce88986bdf117c"},{"type":"WEB","url":"https://git.kernel.org/stable/c/a1dabe68fb53730bc0be60c5dbfd3f4c560084e7"},{"type":"WEB","url":"https://git.kernel.org/stable/c/d787d509bdf6c88c85e095247daf7456cb7fb772"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89500.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89500"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"8e7b58c27b3c567316a51079b375b846f9223bba"},{"fixed":"a1dabe68fb53730bc0be60c5dbfd3f4c560084e7"},{"fixed":"d787d509bdf6c88c85e095247daf7456cb7fb772"},{"fixed":"7a1fb95de5404134f8758c1295ce88986bdf117c"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-89500.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"6.8.0"},{"fixed":"6.18.51"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.2.4"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-89500.json"}}],"schema_version":"1.9.0"}