CVE-2026-98478
Received Received - Intake

Deadlock in Linux Kernel UFS Core Due to Tagset Quiescing

Vulnerability report for CVE-2026-98478, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.

Publication date: 2026-10-18

Last updated on: 2026-10-18

Assigner: kernel.org

Description

In the Linux kernel, the following vulnerability has been resolved: scsi: ufs: core: Keep internal commands dispatchable during error handling Commit 08b12cda6c44 ("scsi: ufs: core: Switch to scsi_get_internal_cmd()") switched UFS internal commands to allocate requests on hba->host->pseudo_sdev->request_queue, which shares the host tagset with regular LUNs. During error recovery, ufshcd_err_handling_prepare() calls blk_mq_quiesce_tagset(&hba->host->tag_set), marking all queues in the tagset as quiesced, including pseudo_sdev->request_queue. When ufshcd_verify_dev_init() subsequently issues internal commands (e.g. NOP OUT UPIU) via blk_execute_rq(), blk_mq_run_hw_queue() skips running the quiesced queue, resulting in an unrecoverable circular wait deadlock. Keep quiescing the tagset and unquiesce the pseudo SCSI device on top of that, so internal commands stay dispatchable while the logical units remain quiesced. Re-quiesce the pseudo device before unquiescing the tagset so that quiesce_depth stays balanced. Clock scaling and ufshcd_pause_command_processing() are unaffected: they keep quiescing the whole tagset, internal commands included.

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Meta Information

Published
2026-10-18
Last Modified
2026-10-18
Generated
2026-10-18
EPSS Evaluated
N/A
NVD
EUVD

Affected Vendors & Products

Showing 3 associated CPEs
Vendor Product Version / Range
Linux Linux 08b12cda6c44dc015bcc152613c35ee0ae8f37b9
Linux Linux 08b12cda6c44dc015bcc152613c35ee0ae8f37b9
Linux Linux 6.19

Helpful Resources

Exploitability

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CWE ID Description
CWE-UNKNOWN

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