5.10-stable review patch. If anyone has any objections, please let me know.
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From: Gabriel Krisman Bertazi krisman@collabora.com
[ 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@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 Signed-off-by: Chuck Lever chuck.lever@oracle.com Signed-off-by: Sasha Levin sashal@kernel.org --- 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;