{"id":"CVE-2026-98820","state":"PUBLISHED","title":"blk-mq: set RQF_USE_SCHED when the operation is known","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nblk-mq: set RQF_USE_SCHED when the operation is known\n\nThe cached requests are allocated for one operation but can be handed\nout for another. A passthrough command has RQF_USE_SCHED cleared, so\nusing those flags for a subsequent read/write bio will insert it into\nthe scheduler without ->prepare_request() and frees it without\n->finish_request(). For kyber, this leaks the domain token acquired at\ndispatch and stalls the queue.\n\nDon't set RQF_USE_SCHED based on the first operation the batch happened\nto be allocated for. Instead, set it after the request is claimed by an\noperation. Introduce a helper function, blk_mq_rq_late_init() for this,\nand absorb blk_mq_rq_time_init() since the two run together.","publishedAt":"2026-10-18T15:49:12.251Z","updatedAt":"2026-10-19T09:26:13.210Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"4b6a5d9cea911424e84107df8c4eb8317938d2cd","status":"affected","lessThan":"790730e4d95de8356a573d4b4864486bba731863","versionType":"git"},{"version":"4b6a5d9cea911424e84107df8c4eb8317938d2cd","status":"affected","lessThan":"2c47ebc27fa72078e26177cd458cdaf3006a9685","versionType":"git"},{"version":"4b6a5d9cea911424e84107df8c4eb8317938d2cd","status":"affected","lessThan":"ab6c756f28c741d704a7c3e04814bfc3adf6f818","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["block/blk-mq.c","block/mq-deadline.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.1","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.1","versionType":"semver"},{"version":"6.18.56","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.10","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":["block/blk-mq.c","block/mq-deadline.c"]}],"references":["https://git.kernel.org/stable/c/790730e4d95de8356a573d4b4864486bba731863","https://git.kernel.org/stable/c/2c47ebc27fa72078e26177cd458cdaf3006a9685","https://git.kernel.org/stable/c/ab6c756f28c741d704a7c3e04814bfc3adf6f818"],"weaknesses":[],"ingestedAt":"2026-10-29T20:13:43.249Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/98xxx/CVE-2026-98820.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-98820","state":"PUBLISHED","datePublished":"2026-10-18T15:49:12.251Z","dateUpdated":"2026-10-19T09:26:13.210Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-09-25T10:25:14.372Z"},"containers":{"cna":{"title":"blk-mq: set RQF_USE_SCHED when the operation is known","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nblk-mq: set RQF_USE_SCHED when the operation is known\n\nThe cached requests are allocated for one operation but can be handed\nout for another. A passthrough command has RQF_USE_SCHED cleared, so\nusing those flags for a subsequent read/write bio will insert it into\nthe scheduler without ->prepare_request() and frees it without\n->finish_request(). For kyber, this leaks the domain token acquired at\ndispatch and stalls the queue.\n\nDon't set RQF_USE_SCHED based on the first operation the batch happened\nto be allocated for. Instead, set it after the request is claimed by an\noperation. Introduce a helper function, blk_mq_rq_late_init() for this,\nand absorb blk_mq_rq_time_init() since the two run together."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"4b6a5d9cea911424e84107df8c4eb8317938d2cd","status":"affected","lessThan":"790730e4d95de8356a573d4b4864486bba731863","versionType":"git"},{"version":"4b6a5d9cea911424e84107df8c4eb8317938d2cd","status":"affected","lessThan":"2c47ebc27fa72078e26177cd458cdaf3006a9685","versionType":"git"},{"version":"4b6a5d9cea911424e84107df8c4eb8317938d2cd","status":"affected","lessThan":"ab6c756f28c741d704a7c3e04814bfc3adf6f818","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["block/blk-mq.c","block/mq-deadline.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.1","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.1","versionType":"semver"},{"version":"6.18.56","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.10","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":["block/blk-mq.c","block/mq-deadline.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/790730e4d95de8356a573d4b4864486bba731863"},{"url":"https://git.kernel.org/stable/c/2c47ebc27fa72078e26177cd458cdaf3006a9685"},{"url":"https://git.kernel.org/stable/c/ab6c756f28c741d704a7c3e04814bfc3adf6f818"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-10-19T09:26:13.210Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.1","versionEndExcluding":"6.18.56"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.1","versionEndExcluding":"7.2.10"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.1","versionEndExcluding":"7.3"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}