{"id":"CVE-2026-90185","state":"PUBLISHED","title":"null_blk: serialize configfs attribute stores with the lock","description":"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->NAME 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->NAME\nafterwards. This leaves dev->submit_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->zones[] 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.","publishedAt":"2026-09-17T16:07:08.392Z","updatedAt":"2026-10-19T08:59:22.077Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"45919fbfe1c487c17ea1d198534339a5e8abeae3","status":"affected","lessThan":"8e839ed5210399a0330a8a6c5885c1d40a537c6d","versionType":"git"},{"version":"45919fbfe1c487c17ea1d198534339a5e8abeae3","status":"affected","lessThan":"88d806d0e1d36246208386a8e55b511c1b3d647c","versionType":"git"},{"version":"45919fbfe1c487c17ea1d198534339a5e8abeae3","status":"affected","lessThan":"3945ce8cbce4e328e6fdf0b522dc71e340de19db","versionType":"git"},{"version":"45919fbfe1c487c17ea1d198534339a5e8abeae3","status":"affected","lessThan":"65cae82fd3c39b53430672cb9e3ecd267471a6ce","versionType":"git"},{"version":"45919fbfe1c487c17ea1d198534339a5e8abeae3","status":"affected","lessThan":"c70994c2862b05e44728912b2ea9487d31e2aea7","versionType":"git"},{"version":"45919fbfe1c487c17ea1d198534339a5e8abeae3","status":"affected","lessThan":"7e7fff51808237703a3a1df6dd5cae1dfd1db86d","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/block/null_blk/main.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.5","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.5","versionType":"semver"},{"version":"6.1.188","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.157","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.110","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.52","status":"unaffected","lessThanOrEqual":"6.18.*","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/block/null_blk/main.c"]}],"references":["https://git.kernel.org/stable/c/8e839ed5210399a0330a8a6c5885c1d40a537c6d","https://git.kernel.org/stable/c/88d806d0e1d36246208386a8e55b511c1b3d647c","https://git.kernel.org/stable/c/3945ce8cbce4e328e6fdf0b522dc71e340de19db","https://git.kernel.org/stable/c/65cae82fd3c39b53430672cb9e3ecd267471a6ce","https://git.kernel.org/stable/c/c70994c2862b05e44728912b2ea9487d31e2aea7","https://git.kernel.org/stable/c/7e7fff51808237703a3a1df6dd5cae1dfd1db86d"],"weaknesses":[],"ingestedAt":"2026-10-29T20:13:34.582Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/90xxx/CVE-2026-90185.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-90185","state":"PUBLISHED","datePublished":"2026-09-17T16:07:08.392Z","dateUpdated":"2026-10-19T08:59:22.077Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-09-11T19:38:34.791Z"},"containers":{"cna":{"title":"null_blk: serialize configfs attribute stores with the lock","descriptions":[{"lang":"en","value":"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->NAME 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->NAME\nafterwards. This leaves dev->submit_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->zones[] 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."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"45919fbfe1c487c17ea1d198534339a5e8abeae3","status":"affected","lessThan":"8e839ed5210399a0330a8a6c5885c1d40a537c6d","versionType":"git"},{"version":"45919fbfe1c487c17ea1d198534339a5e8abeae3","status":"affected","lessThan":"88d806d0e1d36246208386a8e55b511c1b3d647c","versionType":"git"},{"version":"45919fbfe1c487c17ea1d198534339a5e8abeae3","status":"affected","lessThan":"3945ce8cbce4e328e6fdf0b522dc71e340de19db","versionType":"git"},{"version":"45919fbfe1c487c17ea1d198534339a5e8abeae3","status":"affected","lessThan":"65cae82fd3c39b53430672cb9e3ecd267471a6ce","versionType":"git"},{"version":"45919fbfe1c487c17ea1d198534339a5e8abeae3","status":"affected","lessThan":"c70994c2862b05e44728912b2ea9487d31e2aea7","versionType":"git"},{"version":"45919fbfe1c487c17ea1d198534339a5e8abeae3","status":"affected","lessThan":"7e7fff51808237703a3a1df6dd5cae1dfd1db86d","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/block/null_blk/main.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.5","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.5","versionType":"semver"},{"version":"6.1.188","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.157","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.110","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.52","status":"unaffected","lessThanOrEqual":"6.18.*","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/block/null_blk/main.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/8e839ed5210399a0330a8a6c5885c1d40a537c6d"},{"url":"https://git.kernel.org/stable/c/88d806d0e1d36246208386a8e55b511c1b3d647c"},{"url":"https://git.kernel.org/stable/c/3945ce8cbce4e328e6fdf0b522dc71e340de19db"},{"url":"https://git.kernel.org/stable/c/65cae82fd3c39b53430672cb9e3ecd267471a6ce"},{"url":"https://git.kernel.org/stable/c/c70994c2862b05e44728912b2ea9487d31e2aea7"},{"url":"https://git.kernel.org/stable/c/7e7fff51808237703a3a1df6dd5cae1dfd1db86d"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-10-19T08:59:22.077Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.5","versionEndExcluding":"6.1.188"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.5","versionEndExcluding":"6.6.157"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.5","versionEndExcluding":"6.12.110"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.5","versionEndExcluding":"6.18.52"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.5","versionEndExcluding":"7.2.6"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.5","versionEndExcluding":"7.3"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}