{"id":"CVE-2026-90185","summary":"null_blk: serialize configfs attribute stores with the lock","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nnull_blk: serialize configfs attribute stores with the lock\n\nThe NULLB_DEVICE_ATTR _store takes no lock: apply_fn attributes\n(submit_queues, poll_queues) get dev-\u003eNAME written again after apply_fn\nreturns, outside its lock; APPLY=NULL attributes are entirely lockless.\nconfigfs only serializes stores per-open-file, so concurrent stores on\nseparate fds race.\n\nFor apply_fn attributes, once one store's apply_fn has reconfigured the\nhardware, a second (losing) store can still overwrite dev-\u003eNAME\nafterwards. This leaves dev-\u003esubmit_queues out of sync with the live\nqueue count, which is later caught by the WARN_ON_ONCE() in\nnull_map_queues().\n\nFor !apply_fn attributes, power_store()'s null_add_dev() validates and\nbuilds the device under \"lock\" but only sets CONFIGURED afterwards. A store\nslipping in during this window can change a field mid-setup -- for example,\nzone_nr_conv can be pushed above nr_zones after it has already been\nclamped, leading to an out-of-bounds dev-\u003ezones[] access.\n\nTake \"lock\" in the macro around the apply_fn call, the CONFIGURED test and\nthe field write, and move it out of nullb_apply_submit_queues()/\nnullb_apply_poll_queues() so both paths are covered once. This serializes\nstores with power_store's setup and with each other.","modified":"2026-09-18T03:48:36.274148834Z","published":"2026-09-17T16:07:08.392Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/90xxx/CVE-2026-90185.json","cna_assigner":"Linux"},"references":[{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"},{"type":"WEB","url":"https://git.kernel.org/stable/c/3945ce8cbce4e328e6fdf0b522dc71e340de19db"},{"type":"WEB","url":"https://git.kernel.org/stable/c/65cae82fd3c39b53430672cb9e3ecd267471a6ce"},{"type":"WEB","url":"https://git.kernel.org/stable/c/7e7fff51808237703a3a1df6dd5cae1dfd1db86d"},{"type":"WEB","url":"https://git.kernel.org/stable/c/88d806d0e1d36246208386a8e55b511c1b3d647c"},{"type":"WEB","url":"https://git.kernel.org/stable/c/8e839ed5210399a0330a8a6c5885c1d40a537c6d"},{"type":"WEB","url":"https://git.kernel.org/stable/c/c70994c2862b05e44728912b2ea9487d31e2aea7"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/90xxx/CVE-2026-90185.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-90185"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"45919fbfe1c487c17ea1d198534339a5e8abeae3"},{"fixed":"8e839ed5210399a0330a8a6c5885c1d40a537c6d"},{"fixed":"88d806d0e1d36246208386a8e55b511c1b3d647c"},{"fixed":"3945ce8cbce4e328e6fdf0b522dc71e340de19db"},{"fixed":"65cae82fd3c39b53430672cb9e3ecd267471a6ce"},{"fixed":"c70994c2862b05e44728912b2ea9487d31e2aea7"},{"fixed":"7e7fff51808237703a3a1df6dd5cae1dfd1db86d"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-90185.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"5.5.0"},{"fixed":"6.1.188"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.157"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.110"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.52"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.2.6"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-90185.json"}}],"schema_version":"1.9.0"}