{"api_version":"1","generated_at":"2026-09-12T03:12:54+00:00","cve":"CVE-2026-89771","urls":{"html":"https://cve.report/CVE-2026-89771","api":"https://cve.report/api/cve/CVE-2026-89771.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-89771","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-89771"},"summary":{"title":"ring-buffer: Fix subbuf resize race with ring buffer readers","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nring-buffer: Fix subbuf resize race with ring buffer readers\n\ntrace_buffer subbuf_size is read lockless in ring_buffer_read_page() and\nring_buffer_read_start(), while it can simultaneously be resized with\nring_buffer_subbuf_order_set().\n\nInstead of trace_buffer::subbuf_size, use bpage::order in\nring_buffer_read_start() and ring_buffer_read_page().\n\nIn ring_buffer_read_start(), even with resize_disabled, there is still a\npossibility of a race with a buffer modification. Hold the trace_buffer\nmutex to synchronise with any pending ring buffer order modification.\n\ntrace_buffer::subbuf_size is now actually useless, remove it. Also,\ncreate accessors rb_subbuf_capacity() and rb_page_capacity() which\nreturn the actual size available for storing events, while\nrb_subbuf_size() returns the actual subbuf page-size.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-09-11 20:20:08","updated_at":"2026-09-11 20:20:08"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/6d666f0b8b36c0765cf19fbe6de5a7ba5a73aad9","name":"https://git.kernel.org/stable/c/6d666f0b8b36c0765cf19fbe6de5a7ba5a73aad9","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/50f4a793c4ff24826efb0ac700989a5063cc53df","name":"https://git.kernel.org/stable/c/50f4a793c4ff24826efb0ac700989a5063cc53df","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/8a5f63637890f03177146efddaba5ec7a1b4d61f","name":"https://git.kernel.org/stable/c/8a5f63637890f03177146efddaba5ec7a1b4d61f","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/0c7c517827a453128a8f58bfd849546a29813b27","name":"https://git.kernel.org/stable/c/0c7c517827a453128a8f58bfd849546a29813b27","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-89771","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89771","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected f9b94daa542a8d2532f0930f01cd9aec2d19621b 6d666f0b8b36c0765cf19fbe6de5a7ba5a73aad9 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected f9b94daa542a8d2532f0930f01cd9aec2d19621b 50f4a793c4ff24826efb0ac700989a5063cc53df git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected f9b94daa542a8d2532f0930f01cd9aec2d19621b 0c7c517827a453128a8f58bfd849546a29813b27 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected f9b94daa542a8d2532f0930f01cd9aec2d19621b 8a5f63637890f03177146efddaba5ec7a1b4d61f git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.8","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.8 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.109 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.50 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2.4 7.2.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.3-rc1 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["kernel/trace/ring_buffer.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"6d666f0b8b36c0765cf19fbe6de5a7ba5a73aad9","status":"affected","version":"f9b94daa542a8d2532f0930f01cd9aec2d19621b","versionType":"git"},{"lessThan":"50f4a793c4ff24826efb0ac700989a5063cc53df","status":"affected","version":"f9b94daa542a8d2532f0930f01cd9aec2d19621b","versionType":"git"},{"lessThan":"0c7c517827a453128a8f58bfd849546a29813b27","status":"affected","version":"f9b94daa542a8d2532f0930f01cd9aec2d19621b","versionType":"git"},{"lessThan":"8a5f63637890f03177146efddaba5ec7a1b4d61f","status":"affected","version":"f9b94daa542a8d2532f0930f01cd9aec2d19621b","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["kernel/trace/ring_buffer.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"6.8"},{"lessThan":"6.8","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.109","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.50","versionType":"semver"},{"lessThanOrEqual":"7.2.*","status":"unaffected","version":"7.2.4","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.3-rc1","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.109","versionStartIncluding":"6.8","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.50","versionStartIncluding":"6.8","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2.4","versionStartIncluding":"6.8","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.3-rc1","versionStartIncluding":"6.8","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nring-buffer: Fix subbuf resize race with ring buffer readers\n\ntrace_buffer subbuf_size is read lockless in ring_buffer_read_page() and\nring_buffer_read_start(), while it can simultaneously be resized with\nring_buffer_subbuf_order_set().\n\nInstead of trace_buffer::subbuf_size, use bpage::order in\nring_buffer_read_start() and ring_buffer_read_page().\n\nIn ring_buffer_read_start(), even with resize_disabled, there is still a\npossibility of a race with a buffer modification. Hold the trace_buffer\nmutex to synchronise with any pending ring buffer order modification.\n\ntrace_buffer::subbuf_size is now actually useless, remove it. Also,\ncreate accessors rb_subbuf_capacity() and rb_page_capacity() which\nreturn the actual size available for storing events, while\nrb_subbuf_size() returns the actual subbuf page-size."}],"providerMetadata":{"dateUpdated":"2026-09-11T19:47:10.381Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/6d666f0b8b36c0765cf19fbe6de5a7ba5a73aad9"},{"url":"https://git.kernel.org/stable/c/50f4a793c4ff24826efb0ac700989a5063cc53df"},{"url":"https://git.kernel.org/stable/c/0c7c517827a453128a8f58bfd849546a29813b27"},{"url":"https://git.kernel.org/stable/c/8a5f63637890f03177146efddaba5ec7a1b4d61f"}],"title":"ring-buffer: Fix subbuf resize race with ring buffer readers","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-89771","datePublished":"2026-09-11T19:47:10.381Z","dateReserved":"2026-09-11T19:38:34.765Z","dateUpdated":"2026-09-11T19:47:10.381Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-09-11 20:20:08","lastModifiedDate":"2026-09-11 20:20:08","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"89771","Ordinal":"1","Title":"ring-buffer: Fix subbuf resize race with ring buffer readers","CVE":"CVE-2026-89771","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"89771","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nring-buffer: Fix subbuf resize race with ring buffer readers\n\ntrace_buffer subbuf_size is read lockless in ring_buffer_read_page() and\nring_buffer_read_start(), while it can simultaneously be resized with\nring_buffer_subbuf_order_set().\n\nInstead of trace_buffer::subbuf_size, use bpage::order in\nring_buffer_read_start() and ring_buffer_read_page().\n\nIn ring_buffer_read_start(), even with resize_disabled, there is still a\npossibility of a race with a buffer modification. Hold the trace_buffer\nmutex to synchronise with any pending ring buffer order modification.\n\ntrace_buffer::subbuf_size is now actually useless, remove it. Also,\ncreate accessors rb_subbuf_capacity() and rb_page_capacity() which\nreturn the actual size available for storing events, while\nrb_subbuf_size() returns the actual subbuf page-size.","Type":"Description","Title":"ring-buffer: Fix subbuf resize race with ring buffer readers"}]}}}