fanotify: Allow file handle encoding for unhashed events

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>
This commit is contained in:
Gabriel Krisman Bertazi 2021-10-25 16:27:29 -03:00 committed by Jan Kara
parent 12f47bf0f0
commit 74fe473489

View file

@ -403,8 +403,12 @@ static int fanotify_encode_fh(struct fanotify_fh *fh, struct inode *inode,
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;