zfs_get_name() expects a parameter of type zfs_handle_t *zhp , but
gets an invalid parameter type of zfs_handle_t **zhp actually in
libzfs_dataset_cmp(), which may trigger a coredump if called.
libzfs_dataset_cmp() working normally so far, just because all the
callers only give datasets of type ZFS_TYPE_FILESYSTEM to it, we
compared their mountpoint and return, luckily.
Signed-off-by: GeLiXin <ge.lixin@zte.com.cn>
Signed-off-by: Tim Chase <tim@chase2k.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#4919