CVE-2024-26982

Summary

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

Squashfs: check the inode number is not the invalid value of zero

Syskiller has produced an out of bounds access in fill_meta_index().

That out of bounds access is ultimately caused because the inode has an inode number with the invalid value of zero, which was not checked.

The reason this causes the out of bounds access is due to following sequence of events:

  1. Fill_meta_index() is called to allocate (via empty_meta_index()) and fill a metadata index. It however suffers a data read error and aborts, invalidating the newly returned empty metadata index. It does this by setting the inode number of the index to zero, which means unused (zero is not a valid inode number).

  2. When fill_meta_index() is subsequently called again on another read operation, locate_meta_index() returns the previous index because it matches the inode number of 0. Because this index has been returned it is expected to have been filled, and because it hasn't been, an out of bounds access is performed.

This patch adds a sanity check which checks that the inode number is not zero when the inode is created and returns -EINVAL if it is.

[phillip@squashfs.org.uk: whitespace fix]

Affected Software

VendorProductVersion RangeStatus
LinuxLinux6545b246a2c815a8fcd07d58240effb6ec3481b1 < 32c114a58236fe67141634774559f21f1dc96fd7affected
LinuxLinux6545b246a2c815a8fcd07d58240effb6ec3481b1 < 4a1b6f89825e267e156ccaeba3d235edcac77f94affected
LinuxLinux6545b246a2c815a8fcd07d58240effb6ec3481b1 < cf46f88b92cfc0e32bd8a21ba1273cff13b8745faffected
LinuxLinux6545b246a2c815a8fcd07d58240effb6ec3481b1 < 5b99dea79650b50909c50aba24fbae00f203f013affected
LinuxLinux6545b246a2c815a8fcd07d58240effb6ec3481b1 < be383effaee3d89034f0828038f95065b518772eaffected
LinuxLinux6545b246a2c815a8fcd07d58240effb6ec3481b1 < 7def00ebc9f2d6a581ddf46ce4541f84a10680e5affected
LinuxLinux6545b246a2c815a8fcd07d58240effb6ec3481b1 < 9253c54e01b6505d348afbc02abaa4d9f8a01395affected
LinuxLinux2.6.29affected
LinuxLinux0 < 2.6.29unaffected
LinuxLinux5.4.291 <= 5.4.*unaffected
LinuxLinux5.10.235 <= 5.10.*unaffected
LinuxLinux5.15.179 <= 5.15.*unaffected
LinuxLinux6.1.130 <= 6.1.*unaffected
LinuxLinux6.6.30 <= 6.6.*unaffected
LinuxLinux6.8.8 <= 6.8.*unaffected
LinuxLinux6.9 <= *unaffected

Weaknesses

ADP Enrichment

CVE Program Container

Additional References

CISA ADP Vulnrichment

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

Additional References

References