{"api_version":"1","generated_at":"2026-09-21T20:31:45+00:00","cve":"CVE-2026-90184","urls":{"html":"https://cve.report/CVE-2026-90184","api":"https://cve.report/api/cve/CVE-2026-90184.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-90184","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-90184"},"summary":{"title":"null_blk: serialize configfs attribute updates with device setup","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnull_blk: serialize configfs attribute updates with device setup\n\nThe attribute store methods generated with NULLB_DEVICE_ATTR() refuse to\nchange the configuration of a live device by testing\nNULLB_DEV_FL_CONFIGURED, but that flag is only set by\nnullb_device_power_store() after null_add_dev() has returned, and the\nstore methods take no lock at all. configfs only serializes writes to\nthe same open file (buffer->mutex), so a write to any attribute can run\nconcurrently with null_add_dev() and change the device configuration\nwhile it is being used.\n\nnull_add_dev() reads the configuration several times, e.g. dev->zoned is\nread once to set up the queue limits and once to initialize the zone\nresources:\n\n  CPU0: echo 1 > nullb0/power         CPU1: echo 1 > nullb0/zoned\n  nullb_device_power_store()\n    mutex_lock(&lock)\n    null_add_dev()\n      if (dev->zoned) -> false\n        /* no BLK_FEAT_ZONED */       nullb_device_zoned_store()\n                                        test_bit(FL_CONFIGURED) -> 0\n                                        dev->zoned = true\n      blk_mq_alloc_disk()\n        /* queue is not zoned */\n      if (nullb->dev->zoned) -> true\n        null_register_zoned_dev()\n          blk_revalidate_disk_zones()\n\nblk_revalidate_disk_zones() is then called for a queue that does not\nhave BLK_FEAT_ZONED set, which triggers its WARN_ON_ONCE() and fails the\ndevice setup with -EIO:\n\n  WARNING: CPU: 2 PID: 322 at block/blk-zoned.c:2357 blk_revalidate_disk_zones+0x4c/0x560\n\nClearing dev->zoned in the same window is worse: the queue is created\nwith BLK_FEAT_ZONED but the zone resources are never initialized, so\nadd_disk() succeeds for a zoned disk that has no zones. And a store that\nlands after the last dev->zoned test leaves dev->zoned set while\ndev->zones is still NULL, which null_process_zoned_cmd() dereferences on\nthe first write.\n\nFix this by taking the global lock, which nullb_device_power_store()\nalready holds across null_add_dev() and null_del_dev(), around both the\nNULLB_DEV_FL_CONFIGURED test and the update of the device configuration.\nThe submit_queues and poll_queues apply callbacks are now called with\nthat lock held, so remove the locking they did themselves.\n\nSince the store methods can run as soon as configfs_register_subsystem()\nreturns, that is, before null_init() gets to mutex_init(&lock), also\ninitialize the lock statically with DEFINE_MUTEX().","state":"PUBLISHED","assigner":"Linux","published_at":"2026-09-17 17:17:12","updated_at":"2026-09-17 17:17:12"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/7de792b4c48fba02a36a8077032f7d5093c925e5","name":"https://git.kernel.org/stable/c/7de792b4c48fba02a36a8077032f7d5093c925e5","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/d3d35dd045a35991bf6fd13de5f293e6dd7bf3b3","name":"https://git.kernel.org/stable/c/d3d35dd045a35991bf6fd13de5f293e6dd7bf3b3","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/32456a85995579e56c60cc53c357cda75a9d4f7c","name":"https://git.kernel.org/stable/c/32456a85995579e56c60cc53c357cda75a9d4f7c","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/4e1f23f9c33c156be7e313b40695af5a3a834739","name":"https://git.kernel.org/stable/c/4e1f23f9c33c156be7e313b40695af5a3a834739","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/aed8af338a09a64d63b068a803c4ecfc5701dd4c","name":"https://git.kernel.org/stable/c/aed8af338a09a64d63b068a803c4ecfc5701dd4c","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/6352e7ead2d8111802a554eeb94886f5a9894bb9","name":"https://git.kernel.org/stable/c/6352e7ead2d8111802a554eeb94886f5a9894bb9","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-90184","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-90184","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 3bf2bd20734e3e6ffda53719a9c10fb3ee9c5ffa 6352e7ead2d8111802a554eeb94886f5a9894bb9 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 3bf2bd20734e3e6ffda53719a9c10fb3ee9c5ffa 7de792b4c48fba02a36a8077032f7d5093c925e5 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 3bf2bd20734e3e6ffda53719a9c10fb3ee9c5ffa aed8af338a09a64d63b068a803c4ecfc5701dd4c git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 3bf2bd20734e3e6ffda53719a9c10fb3ee9c5ffa 32456a85995579e56c60cc53c357cda75a9d4f7c git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 3bf2bd20734e3e6ffda53719a9c10fb3ee9c5ffa d3d35dd045a35991bf6fd13de5f293e6dd7bf3b3 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 3bf2bd20734e3e6ffda53719a9c10fb3ee9c5ffa 4e1f23f9c33c156be7e313b40695af5a3a834739 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 4.14","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 4.14 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.1.188 6.1.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.6.157 6.6.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.110 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.52 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2.6 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":["drivers/block/null_blk/main.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"6352e7ead2d8111802a554eeb94886f5a9894bb9","status":"affected","version":"3bf2bd20734e3e6ffda53719a9c10fb3ee9c5ffa","versionType":"git"},{"lessThan":"7de792b4c48fba02a36a8077032f7d5093c925e5","status":"affected","version":"3bf2bd20734e3e6ffda53719a9c10fb3ee9c5ffa","versionType":"git"},{"lessThan":"aed8af338a09a64d63b068a803c4ecfc5701dd4c","status":"affected","version":"3bf2bd20734e3e6ffda53719a9c10fb3ee9c5ffa","versionType":"git"},{"lessThan":"32456a85995579e56c60cc53c357cda75a9d4f7c","status":"affected","version":"3bf2bd20734e3e6ffda53719a9c10fb3ee9c5ffa","versionType":"git"},{"lessThan":"d3d35dd045a35991bf6fd13de5f293e6dd7bf3b3","status":"affected","version":"3bf2bd20734e3e6ffda53719a9c10fb3ee9c5ffa","versionType":"git"},{"lessThan":"4e1f23f9c33c156be7e313b40695af5a3a834739","status":"affected","version":"3bf2bd20734e3e6ffda53719a9c10fb3ee9c5ffa","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["drivers/block/null_blk/main.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"4.14"},{"lessThan":"4.14","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.1.*","status":"unaffected","version":"6.1.188","versionType":"semver"},{"lessThanOrEqual":"6.6.*","status":"unaffected","version":"6.6.157","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.110","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.52","versionType":"semver"},{"lessThanOrEqual":"7.2.*","status":"unaffected","version":"7.2.6","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":"6.1.188","versionStartIncluding":"4.14","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.6.157","versionStartIncluding":"4.14","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.110","versionStartIncluding":"4.14","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.52","versionStartIncluding":"4.14","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2.6","versionStartIncluding":"4.14","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.3-rc1","versionStartIncluding":"4.14","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnull_blk: serialize configfs attribute updates with device setup\n\nThe attribute store methods generated with NULLB_DEVICE_ATTR() refuse to\nchange the configuration of a live device by testing\nNULLB_DEV_FL_CONFIGURED, but that flag is only set by\nnullb_device_power_store() after null_add_dev() has returned, and the\nstore methods take no lock at all. configfs only serializes writes to\nthe same open file (buffer->mutex), so a write to any attribute can run\nconcurrently with null_add_dev() and change the device configuration\nwhile it is being used.\n\nnull_add_dev() reads the configuration several times, e.g. dev->zoned is\nread once to set up the queue limits and once to initialize the zone\nresources:\n\n  CPU0: echo 1 > nullb0/power         CPU1: echo 1 > nullb0/zoned\n  nullb_device_power_store()\n    mutex_lock(&lock)\n    null_add_dev()\n      if (dev->zoned) -> false\n        /* no BLK_FEAT_ZONED */       nullb_device_zoned_store()\n                                        test_bit(FL_CONFIGURED) -> 0\n                                        dev->zoned = true\n      blk_mq_alloc_disk()\n        /* queue is not zoned */\n      if (nullb->dev->zoned) -> true\n        null_register_zoned_dev()\n          blk_revalidate_disk_zones()\n\nblk_revalidate_disk_zones() is then called for a queue that does not\nhave BLK_FEAT_ZONED set, which triggers its WARN_ON_ONCE() and fails the\ndevice setup with -EIO:\n\n  WARNING: CPU: 2 PID: 322 at block/blk-zoned.c:2357 blk_revalidate_disk_zones+0x4c/0x560\n\nClearing dev->zoned in the same window is worse: the queue is created\nwith BLK_FEAT_ZONED but the zone resources are never initialized, so\nadd_disk() succeeds for a zoned disk that has no zones. And a store that\nlands after the last dev->zoned test leaves dev->zoned set while\ndev->zones is still NULL, which null_process_zoned_cmd() dereferences on\nthe first write.\n\nFix this by taking the global lock, which nullb_device_power_store()\nalready holds across null_add_dev() and null_del_dev(), around both the\nNULLB_DEV_FL_CONFIGURED test and the update of the device configuration.\nThe submit_queues and poll_queues apply callbacks are now called with\nthat lock held, so remove the locking they did themselves.\n\nSince the store methods can run as soon as configfs_register_subsystem()\nreturns, that is, before null_init() gets to mutex_init(&lock), also\ninitialize the lock statically with DEFINE_MUTEX()."}],"providerMetadata":{"dateUpdated":"2026-09-17T16:07:07.728Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/6352e7ead2d8111802a554eeb94886f5a9894bb9"},{"url":"https://git.kernel.org/stable/c/7de792b4c48fba02a36a8077032f7d5093c925e5"},{"url":"https://git.kernel.org/stable/c/aed8af338a09a64d63b068a803c4ecfc5701dd4c"},{"url":"https://git.kernel.org/stable/c/32456a85995579e56c60cc53c357cda75a9d4f7c"},{"url":"https://git.kernel.org/stable/c/d3d35dd045a35991bf6fd13de5f293e6dd7bf3b3"},{"url":"https://git.kernel.org/stable/c/4e1f23f9c33c156be7e313b40695af5a3a834739"}],"title":"null_blk: serialize configfs attribute updates with device setup","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-90184","datePublished":"2026-09-17T16:07:07.728Z","dateReserved":"2026-09-11T19:38:34.791Z","dateUpdated":"2026-09-17T16:07:07.728Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-09-17 17:17:12","lastModifiedDate":"2026-09-17 17:17:12","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"90184","Ordinal":"1","Title":"null_blk: serialize configfs attribute updates with device setup","CVE":"CVE-2026-90184","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"90184","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nnull_blk: serialize configfs attribute updates with device setup\n\nThe attribute store methods generated with NULLB_DEVICE_ATTR() refuse to\nchange the configuration of a live device by testing\nNULLB_DEV_FL_CONFIGURED, but that flag is only set by\nnullb_device_power_store() after null_add_dev() has returned, and the\nstore methods take no lock at all. configfs only serializes writes to\nthe same open file (buffer->mutex), so a write to any attribute can run\nconcurrently with null_add_dev() and change the device configuration\nwhile it is being used.\n\nnull_add_dev() reads the configuration several times, e.g. dev->zoned is\nread once to set up the queue limits and once to initialize the zone\nresources:\n\n  CPU0: echo 1 > nullb0/power         CPU1: echo 1 > nullb0/zoned\n  nullb_device_power_store()\n    mutex_lock(&lock)\n    null_add_dev()\n      if (dev->zoned) -> false\n        /* no BLK_FEAT_ZONED */       nullb_device_zoned_store()\n                                        test_bit(FL_CONFIGURED) -> 0\n                                        dev->zoned = true\n      blk_mq_alloc_disk()\n        /* queue is not zoned */\n      if (nullb->dev->zoned) -> true\n        null_register_zoned_dev()\n          blk_revalidate_disk_zones()\n\nblk_revalidate_disk_zones() is then called for a queue that does not\nhave BLK_FEAT_ZONED set, which triggers its WARN_ON_ONCE() and fails the\ndevice setup with -EIO:\n\n  WARNING: CPU: 2 PID: 322 at block/blk-zoned.c:2357 blk_revalidate_disk_zones+0x4c/0x560\n\nClearing dev->zoned in the same window is worse: the queue is created\nwith BLK_FEAT_ZONED but the zone resources are never initialized, so\nadd_disk() succeeds for a zoned disk that has no zones. And a store that\nlands after the last dev->zoned test leaves dev->zoned set while\ndev->zones is still NULL, which null_process_zoned_cmd() dereferences on\nthe first write.\n\nFix this by taking the global lock, which nullb_device_power_store()\nalready holds across null_add_dev() and null_del_dev(), around both the\nNULLB_DEV_FL_CONFIGURED test and the update of the device configuration.\nThe submit_queues and poll_queues apply callbacks are now called with\nthat lock held, so remove the locking they did themselves.\n\nSince the store methods can run as soon as configfs_register_subsystem()\nreturns, that is, before null_init() gets to mutex_init(&lock), also\ninitialize the lock statically with DEFINE_MUTEX().","Type":"Description","Title":"null_blk: serialize configfs attribute updates with device setup"}]}}}