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

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

During backref walking, at find_parent_nodes(), if we are dealing with a
data extent and we get an error while resolving the indirect backrefs, at
resolve_indirect_refs(), or in the while loop that iterates over the refs
in the direct refs rbtree, we end up leaking the inode lists attached to
the direct refs we have in the direct refs rbtree that were not yet added
to the refs ulist passed as argument to find_parent_nodes(). Since they
were not yet added to the refs ulist and prelim_release() does not free
the lists, on error the caller can only free the lists attached to the
refs that were added to the refs ulist, all the remaining refs get their
inode lists never freed, therefore leaking their memory.

Fix this by having prelim_release() always free any attached inode list
to each ref found in the rbtree, and have find_parent_nodes() set the
ref's inode list to NULL once it transfers ownership of the inode list
to a ref added to the refs ulist passed to find_parent_nodes().

https://git.kernel.org/stable/c/222a3d533027b9492d5b7f5ecdc01a90f57bb5a9

https://git.kernel.org/stable/c/61e06128113711df0534c404fb6bb528eb7d2332

https://git.kernel.org/stable/c/6a6731a0df8c47ecc703bd7bb73459df767051e0

https://git.kernel.org/stable/c/83ea8c5b54d452a5769e605e3c5c687e8ca06d89

https://git.kernel.org/stable/c/92876eec382a0f19f33d09d2c939e9ca49038ae5