CVE-2021-46968

Summary

In the Linux kernel, the following vulnerability has been resolved:

s390/zcrypt: fix zcard and zqueue hot-unplug memleak

Tests with kvm and a kmemdebug kernel showed, that on hot unplug the zcard and zqueue structs for the unplugged card or queue are not properly freed because of a mismatch with get/put for the embedded kref counter.

This fix now adjusts the handling of the kref counters. With init the kref counter starts with 1. This initial value needs to drop to zero with the unregister of the card or queue to trigger the release and free the object.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux29c2680fd2bf3862ff5cf2957f198512493156f9 < 026499a9c2e002e621ad568d1378324ae97e5524affected
LinuxLinux29c2680fd2bf3862ff5cf2957f198512493156f9 < 055a063a18bcd19b93709e3eac8078d6b2f04599affected
LinuxLinux29c2680fd2bf3862ff5cf2957f198512493156f9 < 971dc8706cee47393d393905d294ea47e39503d3affected
LinuxLinux29c2680fd2bf3862ff5cf2957f198512493156f9 < 70fac8088cfad9f3b379c9082832b4d7532c16c2affected
LinuxLinux5.10affected
LinuxLinux0 < 5.10unaffected
LinuxLinux5.10.36 <= 5.10.*unaffected
LinuxLinux5.11.20 <= 5.11.*unaffected
LinuxLinux5.12.3 <= 5.12.*unaffected
LinuxLinux5.13 <= *unaffected

Weaknesses

ADP Enrichment

CVE Program Container

Additional References

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: partial

References