[PATCH 0/2] nvmet: avoid configfs recursion when enabling backends

[Runyu Xiao]

The nvmet configfs store callbacks run while configfs holds the item's
frag_sem. Two enable paths then call filp_open() on user-controlled
paths:

- file-backed namespace enable via device_path
- passthru controller enable via passthru_ctrl_path

If either path points back into configfs, the open path re-enters
__configfs_open_file() and tries to take the same frag_sem again.

Resolve the configured path before opening it, reject configfs-backed
paths, and use dentry_open() on the resolved path. This prevents the
configfs recursion without changing valid backend users.

Runyu Xiao (2):
  nvmet: avoid recursive configfs open for file-backed namespaces
  nvmet: avoid recursive configfs open for passthru

 drivers/nvme/target/io-cmd-file.c | 19 ++++++++++++++++++-
 drivers/nvme/target/passthru.c    | 17 ++++++++++++++++-
 2 files changed, 34 insertions(+), 2 deletions(-)

-- 
2.34.1