Bug 2363512 (CVE-2022-49914)

Summary: CVE-2022-49914 kernel: btrfs: fix inode list leak during backref walking at resolve_indirect_refs()
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
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Priority: medium    
Version: unspecifiedCC: dfreiber, drow, jburrell, vkumar
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Hardware: All   
OS: Linux   
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Description OSIDB Bzimport 2025-05-01 15:07:40 UTC
In the Linux kernel, the following vulnerability has been resolved:

btrfs: fix inode list leak during backref walking at resolve_indirect_refs()

During backref walking, at resolve_indirect_refs(), if we get an error
we jump to the 'out' label and call ulist_free() on the 'parents' ulist,
which frees all the elements in the ulist - however that does not free
any inode lists that may be attached to elements, through the 'aux' field
of a ulist node, so we end up leaking lists if we have any attached to
the unodes.

Fix this by calling free_leaf_list() instead of ulist_free() when we exit
from resolve_indirect_refs(). The static function free_leaf_list() is
moved up for this to be possible and it's slightly simplified by removing
unnecessary code.

Comment 1 Avinash Hanwate 2025-05-02 06:19:12 UTC
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2025050106-CVE-2022-49914-42a6@gregkh/T