On Wed, Jun 11, 2025 at 3:02 PM Song Liu [off-list ref] wrote:

Introduce a path iterator, which walks a struct path toward the root.
This path iterator is based on path_walk_parent. A fixed zero'ed root
is passed to path_walk_parent(). Therefore, unless the user terminates
it earlier, the iterator will terminate at the real root.

Signed-off-by: Song Liu <song@kernel.org>
---
 fs/bpf_fs_kfuncs.c    | 72 +++++++++++++++++++++++++++++++++++++++++++
 kernel/bpf/verifier.c |  5 +++
 2 files changed, 77 insertions(+)

LGTM from BPF and open-coded contract POV.

Acked-by: Andrii Nakryiko <andrii@kernel.org>

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