CVE-2021-47041

Name of the Vulnerable Software and Affected Versions Linux kernel versions 5.12.0-rc3 and earlier

Description The vulnerability is related to incorrect locking in the state change sk callback of the nvmet-tcp module. This can cause a deadlock when running nvmet-tcp and nvme-tcp on the same system, where state change callbacks on the host and on the controller side have a causal relationship. The issue is reported by lockdep with blktests, indicating an inconsistent lock state.

Recommendations To resolve this issue, update the Linux kernel to a version that includes the fix for the incorrect locking in the state change sk callback of the nvmet-tcp module. Specifically, versions later than 5.12.0-rc3 should include this fix. If updating is not possible, consider disabling the nvmet-tcp module or restricting its use to minimize the risk of exploitation.