Allow passing a NULL hash to fanotify_encode_fh and avoid calculating
the hash if not needed.
Link: https://lore.kernel.org/r/20211025192746.66445-15-krisman@collabora.com
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
Signed-off-by: Jan Kara <jack@suse.cz>
fh->type = type;
fh->len = fh_len;
- /* Mix fh into event merge key */
- *hash ^= fanotify_hash_fh(fh);
+ /*
+ * Mix fh into event merge key. Hash might be NULL in case of
+ * unhashed FID events (i.e. FAN_FS_ERROR).
+ */
+ if (hash)
+ *hash ^= fanotify_hash_fh(fh);
return FANOTIFY_FH_HDR_LEN + fh_len;