CVE-2024-44963

Summary

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

btrfs: do not BUG_ON() when freeing tree block after error

When freeing a tree block, at btrfs_free_tree_block(), if we fail to create a delayed reference we don't deal with the error and just do a BUG_ON(). The error most likely to happen is -ENOMEM, and we have a comment mentioning that only -ENOMEM can happen, but that is not true, because in case qgroups are enabled any error returned from btrfs_qgroup_trace_extent_post() (can be -EUCLEAN or anything returned from btrfs_search_slot() for example) can be propagated back to btrfs_free_tree_block().

So stop doing a BUG_ON() and return the error to the callers and make them abort the transaction to prevent leaking space. Syzbot was triggering this, likely due to memory allocation failure injection.

Affected Software

VendorProductVersion RangeStatus
LinuxLinuxfb235dc06fac9eaa4408ade9c8b20d45d63c89b7 < 22d907bcd283d69d5e60497fc0d51969545c583baffected
LinuxLinuxfb235dc06fac9eaa4408ade9c8b20d45d63c89b7 < 98251cd60b4d702a8a81de442ab621e83a3fb24faffected
LinuxLinuxfb235dc06fac9eaa4408ade9c8b20d45d63c89b7 < bb3868033a4cccff7be57e9145f2117cbdc91c11affected
LinuxLinux4.11affected
LinuxLinux0 < 4.11unaffected
LinuxLinux6.6.64 <= 6.6.*unaffected
LinuxLinux6.10.5 <= 6.10.*unaffected
LinuxLinux6.11 <= *unaffected

Weaknesses

ADP Enrichment

CISA ADP Vulnrichment

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

References