5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Gabriel Krisman Bertazi <krisman@xxxxxxxxxxxxx> [ Upstream commit 74fe4734897a2da2ae2a665a5e622cd490d36eaf ] 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@xxxxxxxxxxxxx Reviewed-by: Jan Kara <jack@xxxxxxx> Reviewed-by: Amir Goldstein <amir73il@xxxxxxxxx> Signed-off-by: Gabriel Krisman Bertazi <krisman@xxxxxxxxxxxxx> Signed-off-by: Jan Kara <jack@xxxxxxx> Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx> --- fs/notify/fanotify/fanotify.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c index 397ee623ff1e8..ec84fee7ad01c 100644 --- a/fs/notify/fanotify/fanotify.c +++ b/fs/notify/fanotify/fanotify.c @@ -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; -- 2.43.0
