exportfs: check for error return value from exportfs_encode_*()

The exportfs_encode_*() helpers call the filesystem ->encode_fh()
method which returns a signed int.

All the in-tree implementations of ->encode_fh() return a positive
integer and FILEID_INVALID (255) for error.

Fortify the callers for possible future ->encode_fh() implementation
that will return a negative error value.

name_to_handle_at() would propagate the returned error to the users
if filesystem ->encode_fh() method returns an error.

Reported-by: Dan Carpenter <[email protected]>
Link: https://lore.kernel.org/linux-fsdevel/[email protected]/
Signed-off-by: Amir Goldstein <[email protected]>
Reviewed-by: Jeff Layton <[email protected]>
Signed-off-by: Jan Kara <[email protected]>
Message-Id: <[email protected]>

0 files changed, 0 insertions, 0 deletions