CVE-2024-47703

Summary

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

bpf, lsm: Add check for BPF LSM return value

A bpf prog returning a positive number attached to file_alloc_security hook makes kernel panic.

This happens because file system can not filter out the positive number returned by the LSM prog using IS_ERR, and misinterprets this positive number as a file pointer.

Given that hook file_alloc_security never returned positive number before the introduction of BPF LSM, and other BPF LSM hooks may encounter similar issues, this patch adds LSM return value check in verifier, to ensure no unexpected value is returned.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux520b7aa00d8cd8e411ecc09f63a2acd90feb6d29 < 1050727d83e70449991c29dd1cf29fe936a63da3affected
LinuxLinux520b7aa00d8cd8e411ecc09f63a2acd90feb6d29 < 27ca3e20fe80be85a92b10064dfeb56cb2564b1caffected
LinuxLinux520b7aa00d8cd8e411ecc09f63a2acd90feb6d29 < 5d99e198be279045e6ecefe220f5c52f8ce9bfd5affected
LinuxLinux5.7affected
LinuxLinux0 < 5.7unaffected
LinuxLinux6.10.13 <= 6.10.*unaffected
LinuxLinux6.11.2 <= 6.11.*unaffected
LinuxLinux6.12 <= *unaffected

Weaknesses

ADP Enrichment

CISA ADP Vulnrichment

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

References