CVE-2021-46937

Summary

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

mm/damon/dbgfs: fix 'struct pid' leaks in 'dbgfs_target_ids_write()'

DAMON debugfs interface increases the reference counts of 'struct pid's for targets from the 'target_ids' file write callback ('dbgfs_target_ids_write()'), but decreases the counts only in DAMON monitoring termination callback ('dbgfs_before_terminate()').

Therefore, when 'target_ids' file is repeatedly written without DAMON monitoring start/termination, the reference count is not decreased and therefore memory for the 'struct pid' cannot be freed. This commit fixes this issue by decreasing the reference counts when 'target_ids' is written.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux4bc05954d0076655cfaf6f0135585bdc20cd6b11 < ffe4a1ba1a82c416a6b3a09d46594f6a885ae141affected
LinuxLinux4bc05954d0076655cfaf6f0135585bdc20cd6b11 < ebb3f994dd92f8fb4d70c7541091216c1e10cb71affected
LinuxLinux5.15affected
LinuxLinux0 < 5.15unaffected
LinuxLinux5.15.13 <= 5.15.*unaffected
LinuxLinux5.16 <= *unaffected

Weaknesses

ADP Enrichment

CISA ADP Vulnrichment

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

CVE Program Container

Additional References

References