CVE-2026-74392

In the Linux kernel, the following vulnerability has been resolved: dm: limit target bio polling to one shot dm_poll_bio() is the ->poll_bio() callback for a stacked dm device. The caller only knows about the dm queue, so it may decide to do a spinning poll if it thinks a single queue is being polled. Passing those flags unchanged to the mapped clone lets blk_mq_poll() spin on a target queue from inside dm_poll_bio(). With io_uring IOPOLL on a dm-stripe target this can keep a task in dm_poll_bio() -> bio_poll() -> blk_mq_poll() long enough to trigger an RCU CPU stall, before io_uring gets back to io_iopoll_check() and its need_resched() check. Keep dm's ->poll_bio() bounded by forcing one-shot polling for target bios. The caller can invoke dm_poll_bio() again if it wants to keep polling, and it also gets a chance to reap completions or reschedule between passes.

CVSS

No CVSS.

References

Link	Resource
https://git.kernel.org/stable/c/5aa0f9231cbacade065cedd8e9b5ebd067231171
https://git.kernel.org/stable/c/6c4ede3b771adbb3bf21ad4e8b8f2f6f6120c4f7

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-15 06:22

Updated : 2026-08-17 06:19

NVD link : CVE-2026-74392

Mitre link : CVE-2026-74392

CVE.ORG link : CVE-2026-74392

JSON object : View

Products Affected

No product.

CWE

No CWE.

{"id": "CVE-2026-74392", "cveTags": [], "metrics": {}, "affected": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "affectedData": [{"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "f22ecf9c14c12918e30f2179ef516e99eb8b2e49", "lessThan": "6c4ede3b771adbb3bf21ad4e8b8f2f6f6120c4f7", "versionType": "git"}, {"status": "affected", "version": "f22ecf9c14c12918e30f2179ef516e99eb8b2e49", "lessThan": "5aa0f9231cbacade065cedd8e9b5ebd067231171", "versionType": "git"}], "programFiles": ["drivers/md/dm.c"], "defaultStatus": "unaffected"}, {"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "6.19"}, {"status": "unaffected", "version": "0", "lessThan": "6.19", "versionType": "semver"}, {"status": "unaffected", "version": "7.1.5", "versionType": "semver", "lessThanOrEqual": "7.1.*"}, {"status": "unaffected", "version": "7.2", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*"}], "programFiles": ["drivers/md/dm.c"], "defaultStatus": "affected"}]}], "published": "2026-08-15T06:22:41.163", "references": [{"url": "https://git.kernel.org/stable/c/5aa0f9231cbacade065cedd8e9b5ebd067231171", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/6c4ede3b771adbb3bf21ad4e8b8f2f6f6120c4f7", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "vulnStatus": "Received", "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."}], "lastModified": "2026-08-17T06:19:34.260", "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}