{"api_version":"1","generated_at":"2026-10-23T07:20:48+00:00","cve":"CVE-2026-98198","urls":{"html":"https://cve.report/CVE-2026-98198","api":"https://cve.report/api/cve/CVE-2026-98198.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-98198","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-98198"},"summary":{"title":"hwmon: (pwm-fan) Stop RPM timer before freeing tach data","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nhwmon: (pwm-fan) Stop RPM timer before freeing tach data\n\nsample_timer() rearms the RPM timer and accesses the devm-managed\nctx->tachs and ctx->pulses_per_revolution arrays. The cleanup action\nwhich stops the timer is registered before those arrays are allocated.\n\nSince devres releases entries in reverse order, driver detach can free\nthe arrays before pwm_fan_cleanup() shuts down the timer. A timer expiry\nin that window accesses the freed tach data.\n\nWith a KASAN kernel, a test-only kprobe delayed entry to\npwm_fan_cleanup() while normal sysfs unbind ran. Each of three runs\nreported three four-byte reads and two four-byte writes in sample_timer()\nafter its backing devm allocations had been freed. The helper did not\ninvoke the timer callback, cleanup actions or free functions.\n\nWith the fix, three matching unbind runs completed without KASAN, BUG,\nWARNING, Oops or panic. Instrumentation confirmed that timer retirement\ncompleted before the first timer backing allocation was released.\n\nSplit timer retirement from the power cleanup and register its devres\naction after the timer backing data and IRQ actions are installed. This\npreserves the early power rollback action while ensuring the timer is\nretired before its backing data is released. Use timer_shutdown_sync()\nbecause the callback can rearm itself.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-10-06 09:18:05","updated_at":"2026-10-21 13:21:25"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/1e824fdb14a187ce56697e803b02b1e86243a755","name":"https://git.kernel.org/stable/c/1e824fdb14a187ce56697e803b02b1e86243a755","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/d073d306e587c1f35aaf9c07c42e54a3d5895d8f","name":"https://git.kernel.org/stable/c/d073d306e587c1f35aaf9c07c42e54a3d5895d8f","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/a5ce3fe5335a24d0220958c6866830a6d5fa1cc0","name":"https://git.kernel.org/stable/c/a5ce3fe5335a24d0220958c6866830a6d5fa1cc0","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/26d5ff79768548efb1e604bb6e8697c101e06269","name":"https://git.kernel.org/stable/c/26d5ff79768548efb1e604bb6e8697c101e06269","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/b48339b0a577783e4590a69e4cd2f2760ce33154","name":"https://git.kernel.org/stable/c/b48339b0a577783e4590a69e4cd2f2760ce33154","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-98198","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98198","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 01695410d4529e38fea6159fa9f1260c598290b0 d073d306e587c1f35aaf9c07c42e54a3d5895d8f git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 01695410d4529e38fea6159fa9f1260c598290b0 1e824fdb14a187ce56697e803b02b1e86243a755 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 01695410d4529e38fea6159fa9f1260c598290b0 a5ce3fe5335a24d0220958c6866830a6d5fa1cc0 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 01695410d4529e38fea6159fa9f1260c598290b0 b48339b0a577783e4590a69e4cd2f2760ce33154 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 01695410d4529e38fea6159fa9f1260c598290b0 26d5ff79768548efb1e604bb6e8697c101e06269 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 5.12","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 5.12 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.6.160 6.6.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.112 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.54 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2.8 7.2.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.3 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":{"cve_year":"2026","cve_id":"98198","cve":"CVE-2026-98198","epss":"0.001750000","percentile":"0.066730000","score_date":"2026-10-21","updated_at":"2026-10-22 00:15:10"},"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["drivers/hwmon/pwm-fan.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"d073d306e587c1f35aaf9c07c42e54a3d5895d8f","status":"affected","version":"01695410d4529e38fea6159fa9f1260c598290b0","versionType":"git"},{"lessThan":"1e824fdb14a187ce56697e803b02b1e86243a755","status":"affected","version":"01695410d4529e38fea6159fa9f1260c598290b0","versionType":"git"},{"lessThan":"a5ce3fe5335a24d0220958c6866830a6d5fa1cc0","status":"affected","version":"01695410d4529e38fea6159fa9f1260c598290b0","versionType":"git"},{"lessThan":"b48339b0a577783e4590a69e4cd2f2760ce33154","status":"affected","version":"01695410d4529e38fea6159fa9f1260c598290b0","versionType":"git"},{"lessThan":"26d5ff79768548efb1e604bb6e8697c101e06269","status":"affected","version":"01695410d4529e38fea6159fa9f1260c598290b0","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["drivers/hwmon/pwm-fan.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"5.12"},{"lessThan":"5.12","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.6.*","status":"unaffected","version":"6.6.160","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.112","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.54","versionType":"semver"},{"lessThanOrEqual":"7.2.*","status":"unaffected","version":"7.2.8","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.3","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.6.160","versionStartIncluding":"5.12","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.112","versionStartIncluding":"5.12","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.54","versionStartIncluding":"5.12","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2.8","versionStartIncluding":"5.12","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.3","versionStartIncluding":"5.12","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nhwmon: (pwm-fan) Stop RPM timer before freeing tach data\n\nsample_timer() rearms the RPM timer and accesses the devm-managed\nctx->tachs and ctx->pulses_per_revolution arrays. The cleanup action\nwhich stops the timer is registered before those arrays are allocated.\n\nSince devres releases entries in reverse order, driver detach can free\nthe arrays before pwm_fan_cleanup() shuts down the timer. A timer expiry\nin that window accesses the freed tach data.\n\nWith a KASAN kernel, a test-only kprobe delayed entry to\npwm_fan_cleanup() while normal sysfs unbind ran. Each of three runs\nreported three four-byte reads and two four-byte writes in sample_timer()\nafter its backing devm allocations had been freed. The helper did not\ninvoke the timer callback, cleanup actions or free functions.\n\nWith the fix, three matching unbind runs completed without KASAN, BUG,\nWARNING, Oops or panic. Instrumentation confirmed that timer retirement\ncompleted before the first timer backing allocation was released.\n\nSplit timer retirement from the power cleanup and register its devres\naction after the timer backing data and IRQ actions are installed. This\npreserves the early power rollback action while ensuring the timer is\nretired before its backing data is released. Use timer_shutdown_sync()\nbecause the callback can rearm itself."}],"providerMetadata":{"dateUpdated":"2026-10-21T12:54:52.698Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/d073d306e587c1f35aaf9c07c42e54a3d5895d8f"},{"url":"https://git.kernel.org/stable/c/1e824fdb14a187ce56697e803b02b1e86243a755"},{"url":"https://git.kernel.org/stable/c/a5ce3fe5335a24d0220958c6866830a6d5fa1cc0"},{"url":"https://git.kernel.org/stable/c/b48339b0a577783e4590a69e4cd2f2760ce33154"},{"url":"https://git.kernel.org/stable/c/26d5ff79768548efb1e604bb6e8697c101e06269"}],"title":"hwmon: (pwm-fan) Stop RPM timer before freeing tach data","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-98198","datePublished":"2026-10-06T08:44:36.944Z","dateReserved":"2026-09-25T10:25:14.324Z","dateUpdated":"2026-10-21T12:54:52.698Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-10-06 09:18:05","lastModifiedDate":"2026-10-21 13:21:25","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"98198","Ordinal":"1","Title":"hwmon: (pwm-fan) Stop RPM timer before freeing tach data","CVE":"CVE-2026-98198","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"98198","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nhwmon: (pwm-fan) Stop RPM timer before freeing tach data\n\nsample_timer() rearms the RPM timer and accesses the devm-managed\nctx->tachs and ctx->pulses_per_revolution arrays. The cleanup action\nwhich stops the timer is registered before those arrays are allocated.\n\nSince devres releases entries in reverse order, driver detach can free\nthe arrays before pwm_fan_cleanup() shuts down the timer. A timer expiry\nin that window accesses the freed tach data.\n\nWith a KASAN kernel, a test-only kprobe delayed entry to\npwm_fan_cleanup() while normal sysfs unbind ran. Each of three runs\nreported three four-byte reads and two four-byte writes in sample_timer()\nafter its backing devm allocations had been freed. The helper did not\ninvoke the timer callback, cleanup actions or free functions.\n\nWith the fix, three matching unbind runs completed without KASAN, BUG,\nWARNING, Oops or panic. Instrumentation confirmed that timer retirement\ncompleted before the first timer backing allocation was released.\n\nSplit timer retirement from the power cleanup and register its devres\naction after the timer backing data and IRQ actions are installed. This\npreserves the early power rollback action while ensuring the timer is\nretired before its backing data is released. Use timer_shutdown_sync()\nbecause the callback can rearm itself.","Type":"Description","Title":"hwmon: (pwm-fan) Stop RPM timer before freeing tach data"}]}}}