{"id":"CVE-2026-74392","state":"PUBLISHED","title":"dm: limit target bio polling to one shot","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ndm: limit target bio polling to one shot\n\ndm_poll_bio() is the ->poll_bio() callback for a stacked dm device.\nThe caller only knows about the dm queue, so it may decide to do a\nspinning poll if it thinks a single queue is being polled. Passing those\nflags unchanged to the mapped clone lets blk_mq_poll() spin on a target\nqueue from inside dm_poll_bio().\n\nWith io_uring IOPOLL on a dm-stripe target this can keep a task in\n\n  dm_poll_bio() -> bio_poll() -> blk_mq_poll()\n\nlong enough to trigger an RCU CPU stall, before io_uring gets back to\nio_iopoll_check() and its need_resched() check.\n\nKeep dm's ->poll_bio() bounded by forcing one-shot polling for target\nbios. The caller can invoke dm_poll_bio() again if it wants to keep\npolling, and it also gets a chance to reap completions or reschedule\nbetween passes.","publishedAt":"2026-08-15T05:59:05.787Z","updatedAt":"2026-08-17T05:18:31.175Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"f22ecf9c14c12918e30f2179ef516e99eb8b2e49","status":"affected","lessThan":"6c4ede3b771adbb3bf21ad4e8b8f2f6f6120c4f7","versionType":"git"},{"version":"f22ecf9c14c12918e30f2179ef516e99eb8b2e49","status":"affected","lessThan":"5aa0f9231cbacade065cedd8e9b5ebd067231171","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/md/dm.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.19","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.19","versionType":"semver"},{"version":"7.1.5","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/md/dm.c"]}],"references":["https://git.kernel.org/stable/c/6c4ede3b771adbb3bf21ad4e8b8f2f6f6120c4f7","https://git.kernel.org/stable/c/5aa0f9231cbacade065cedd8e9b5ebd067231171"],"weaknesses":[],"ingestedAt":"2026-10-29T20:12:58.252Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/74xxx/CVE-2026-74392.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-74392","state":"PUBLISHED","datePublished":"2026-08-15T05:59:05.787Z","dateUpdated":"2026-08-17T05:18:31.175Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-08-15T05:44:03.891Z"},"containers":{"cna":{"title":"dm: limit target bio polling to one shot","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\ndm: limit target bio polling to one shot\n\ndm_poll_bio() is the ->poll_bio() callback for a stacked dm device.\nThe caller only knows about the dm queue, so it may decide to do a\nspinning poll if it thinks a single queue is being polled. Passing those\nflags unchanged to the mapped clone lets blk_mq_poll() spin on a target\nqueue from inside dm_poll_bio().\n\nWith io_uring IOPOLL on a dm-stripe target this can keep a task in\n\n  dm_poll_bio() -> bio_poll() -> blk_mq_poll()\n\nlong enough to trigger an RCU CPU stall, before io_uring gets back to\nio_iopoll_check() and its need_resched() check.\n\nKeep dm's ->poll_bio() bounded by forcing one-shot polling for target\nbios. The caller can invoke dm_poll_bio() again if it wants to keep\npolling, and it also gets a chance to reap completions or reschedule\nbetween passes."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"f22ecf9c14c12918e30f2179ef516e99eb8b2e49","status":"affected","lessThan":"6c4ede3b771adbb3bf21ad4e8b8f2f6f6120c4f7","versionType":"git"},{"version":"f22ecf9c14c12918e30f2179ef516e99eb8b2e49","status":"affected","lessThan":"5aa0f9231cbacade065cedd8e9b5ebd067231171","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/md/dm.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.19","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.19","versionType":"semver"},{"version":"7.1.5","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/md/dm.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/6c4ede3b771adbb3bf21ad4e8b8f2f6f6120c4f7"},{"url":"https://git.kernel.org/stable/c/5aa0f9231cbacade065cedd8e9b5ebd067231171"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-17T05:18:31.175Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.19","versionEndExcluding":"7.1.5"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.19","versionEndExcluding":"7.2"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}