CVE-2026-74754scsi: core: pair EH runtime PM get and put

Official description

In the Linux kernel, the following vulnerability has been resolved: scsi: core: pair EH runtime PM get and put shost->eh_noresume is currently consulted twice in one error handling iteration: once before scsi_autopm_get_host() and once again before scsi_autopm_put_host(). That is racy when a PM-triggered error path flips shost->eh_noresume while the SCSI EH thread is still running. The problem flow looks like this: PM path ufshcd_set_dev_pwr_mode() shost->eh_noresume = 1 ufshcd_execute_start_stop <-- trigger EH ... shost->eh_noresume = 0 EH path scsi_error_handler() if (!shost->eh_noresume) scsi_autopm_get_host() <-- skipped ... if (!shost->eh_noresume) scsi_autopm_put_host() <-- executed later In that case one EH iteration can skip autoresume on entry and still drop a runtime PM reference on exit. That leaves an unmatched runtime PM put and can trigger a runtime PM usage count underflow. Fix this by making eh_noresume a regular bool so it can be accessed with READ_ONCE() and WRITE_ONCE(). Snapshot it once per EH iteration and use that snapshot for both runtime PM get and put decisions.

Affected packages & fixed versions

Affected products (as reported)

References

• https://git.kernel.org/stable/c/9aca00c74730f4bc12d0717d33db637a16ccdfea
• https://git.kernel.org/stable/c/1ec5f6aa38ea990af37c49af7a4bb3db00da7f9d
• https://git.kernel.org/stable/c/0038a2a75a15d163f428c93103c6d02d4d231a7a
• https://git.kernel.org/stable/c/fdc93f4a801077efbf1b87570ade8d8f325de62f
• https://git.kernel.org/stable/c/e83eed1bea142c8fe852fd53156845b88252ecd8
• https://git.kernel.org/stable/c/872f486259ae0bc6b73ca4735a15d013241f73e9