In the Linux kernel, the following vulnerability has been resolved:
fs/ntfs3: add depth limit to indx_find_buffer to prevent stack overflow
indx_find_buffer() recursively descends the B+ tree index with no depth
limit. A crafted NTFS image with circular index node references causes
unbounded recursion, overflowing the kernel stack and panicking the
system.
This is reachable by mounting a malicious NTFS filesystem (e.g. from a
USB drive via desktop automount) and deleting a file whose index entry
triggers the rebalancing fallback path in indx_delete_entry().
Add a depth parameter and bail out with -EINVAL when it reaches the
fnd->nodes array bound, matching the constraint already enforced by
fnd_push() in indx_find().
The related function indx_find() was previously patched for a similar
infinite-loop issue (commit 1732053c8a6b), but indx_find_buffer() was
missed.
