Fixed
Created: Mar 7, 2024
Updated: Apr 27, 2024
Resolved Date: Apr 19, 2024
Found In Version: 10.23.30.1
Fix Version: 10.23.30.9
Severity: Standard
Applicable for: Wind River Linux LTS 23
Component/s: Kernel
In the Linux kernel, the following vulnerability has been resolved:
scsi: core: Move scsi_host_busy() out of host lock for waking up EH handler
Inside scsi_eh_wakeup(), scsi_host_busy() is called & checked with host
lock every time for deciding if error handler kthread needs to be waken up.
This can be too heavy in case of recovery, such as:
- N hardware queues
- queue depth is M for each hardware queue
- each scsi_host_busy() iterates over (N * M) tag/requests
If recovery is triggered in case that all requests are in-flight, each
scsi_eh_wakeup() is strictly serialized, when scsi_eh_wakeup() is called
for the last in-flight request, scsi_host_busy() has been run for (N * M -
1) times, and request has been iterated for (N*M - 1) * (N * M) times.
If both N and M are big enough, hard lockup can be triggered on acquiring
host lock, and it is observed on mpi3mr(128 hw queues, queue depth 8169).
Fix the issue by calling scsi_host_busy() outside the host lock. We don't
need the host lock for getting busy count because host the lock never
covers that.
mkp: Drop unnecessary 'busy' variables pointed out by Bart]
CREATE(Triage):(User=admin) [CVE-2024-26627 (https://nvd.nist.gov/vuln/detail/CVE-2024-26627)
