{"id":"CVE-2026-90187","published":"2026-09-17T17:17:13.270","lastModified":"2026-09-17T17:17:13.270","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnull_blk: free zones array on device power-off\n\nnull_init_zoned_dev() allocates dev->zones when a zoned device is powered\non, but null_del_dev() never frees it on power-off; dev->zones is only\nfreed later in null_free_dev(), when the configfs directory is removed. If\nthe device is powered off and then on again, null_init_zoned_dev()\nallocates a new array and overwrites the dev->zones pointer, leaking the\nprevious allocation each power cycle.\n\nFree dev->zones in null_del_dev() via null_free_zoned_dev() to solve it.\nAnd calling null_free_zoned_dev() in null_free_dev() is no longer necessary\nbecause every caller already invokes null_del_dev() first: via\nnullb_group_drop_item() before nullb_device_release(), in the\nnull_add_dev() error path of null_create_dev(), and in null_destroy_dev().\nRemove the redundant call.\n\nAnd take &lock around zone_cond_store() in the two store wrappers to\nserialize dev->zones check-and-deref against its alloc/free, which already\nrun under &lock. The reason there was no problem before is that only\nnullb_device_release() or null_exit() frees the dev->zones, which\nguarantees that subsequent users won't access the configfs interface.","cvssScore":null,"cvssSeverity":null,"cvssVector":null,"cwes":[],"vendors":[],"products":[],"references":[{"url":"https://git.kernel.org/stable/c/056be41932c95aabdb3c2967d1ef4978f17a0225","tags":[]},{"url":"https://git.kernel.org/stable/c/0a3afab87124171022fb3579502fa38ef5b311c9","tags":[]},{"url":"https://git.kernel.org/stable/c/2a6357a9b935a34f5508618fee8a7fffbf7722a8","tags":[]},{"url":"https://git.kernel.org/stable/c/b2437d37fcc31fce8a5da1cc1739e284814d2491","tags":[]}],"exploitRefs":[],"hasPoc":false,"ai":null}