{"id":"CVE-2026-93075","state":"PUBLISHED","title":"dax/fsdev: clear pgmap ops and owner on unbind","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ndax/fsdev: clear pgmap ops and owner on unbind\n\nfsdev_dax_probe() sets pgmap->ops = &fsdev_pagemap_ops and\npgmap->owner = dev_dax, but nothing ever clears them. For a dynamic\ndevice the pgmap is devm-allocated and freed on unbind, so this is\nharmless. For a static device the pgmap is the shared, long-lived one\nowned by the dax bus (kill_dev_dax() only NULLs dev_dax->pgmap for the\nnon-static case), and device.c's probe sets only pgmap->type, never\nclearing ops/owner.\n\nSo after fsdev unbinds a static device the stale fsdev_pagemap_ops\nsurvives on the shared pgmap. If the device is then rebound to\ndevice_dax (MEMORY_DEVICE_GENERIC, which installs no ->memory_failure),\nor the fsdev_dax module is unloaded, a subsequent memory_failure on that\npgmap dispatches through the stale -- and possibly freed -- handler.\n\nRegister a devm action that clears pgmap->ops and pgmap->owner on unbind,\nsymmetric with setting them at probe, so the pgmap carries no fsdev state\nonce fsdev is detached.","publishedAt":"2026-09-17T16:10:57.699Z","updatedAt":"2026-10-19T09:05:11.005Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"d5406bd458b0ac10b1301a4d5801d85c8f648637","status":"affected","lessThan":"9b0f91dc9147a8601cec3d4d83cf13c6aaf71b27","versionType":"git"},{"version":"d5406bd458b0ac10b1301a4d5801d85c8f648637","status":"affected","lessThan":"f48884ac31b6bfc99f36b3f207b8c0cbe5d54bd7","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/dax/fsdev.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"7.1","status":"affected"},{"version":"0","status":"unaffected","lessThan":"7.1","versionType":"semver"},{"version":"7.2.6","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/dax/fsdev.c"]}],"references":["https://git.kernel.org/stable/c/9b0f91dc9147a8601cec3d4d83cf13c6aaf71b27","https://git.kernel.org/stable/c/f48884ac31b6bfc99f36b3f207b8c0cbe5d54bd7"],"weaknesses":[],"ingestedAt":"2026-10-29T20:13:34.582Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/93xxx/CVE-2026-93075.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-93075","state":"PUBLISHED","datePublished":"2026-09-17T16:10:57.699Z","dateUpdated":"2026-10-19T09:05:11.005Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-09-17T15:57:05.661Z"},"containers":{"cna":{"title":"dax/fsdev: clear pgmap ops and owner on unbind","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\ndax/fsdev: clear pgmap ops and owner on unbind\n\nfsdev_dax_probe() sets pgmap->ops = &fsdev_pagemap_ops and\npgmap->owner = dev_dax, but nothing ever clears them. For a dynamic\ndevice the pgmap is devm-allocated and freed on unbind, so this is\nharmless. For a static device the pgmap is the shared, long-lived one\nowned by the dax bus (kill_dev_dax() only NULLs dev_dax->pgmap for the\nnon-static case), and device.c's probe sets only pgmap->type, never\nclearing ops/owner.\n\nSo after fsdev unbinds a static device the stale fsdev_pagemap_ops\nsurvives on the shared pgmap. If the device is then rebound to\ndevice_dax (MEMORY_DEVICE_GENERIC, which installs no ->memory_failure),\nor the fsdev_dax module is unloaded, a subsequent memory_failure on that\npgmap dispatches through the stale -- and possibly freed -- handler.\n\nRegister a devm action that clears pgmap->ops and pgmap->owner on unbind,\nsymmetric with setting them at probe, so the pgmap carries no fsdev state\nonce fsdev is detached."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"d5406bd458b0ac10b1301a4d5801d85c8f648637","status":"affected","lessThan":"9b0f91dc9147a8601cec3d4d83cf13c6aaf71b27","versionType":"git"},{"version":"d5406bd458b0ac10b1301a4d5801d85c8f648637","status":"affected","lessThan":"f48884ac31b6bfc99f36b3f207b8c0cbe5d54bd7","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/dax/fsdev.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"7.1","status":"affected"},{"version":"0","status":"unaffected","lessThan":"7.1","versionType":"semver"},{"version":"7.2.6","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/dax/fsdev.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/9b0f91dc9147a8601cec3d4d83cf13c6aaf71b27"},{"url":"https://git.kernel.org/stable/c/f48884ac31b6bfc99f36b3f207b8c0cbe5d54bd7"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-10-19T09:05:11.005Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"7.1","versionEndExcluding":"7.2.6"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"7.1","versionEndExcluding":"7.3"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}