2 files changed, 23 insertions, 3 deletions

diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c
index 6b9c27548997..63c6bb1f8c4d 100644
--- a/fs/notify/fanotify/fanotify.c
+++ b/fs/notify/fanotify/fanotify.c
@@ -346,10 +346,16 @@ static __kernel_fsid_t fanotify_get_fsid(struct fsnotify_iter_info *iter_info)
 	__kernel_fsid_t fsid = {};
 
 	fsnotify_foreach_obj_type(type) {
+		struct fsnotify_mark_connector *conn;
+
 		if (!fsnotify_iter_should_report_type(iter_info, type))
 			continue;
 
-		fsid = iter_info->marks[type]->connector->fsid;
+		conn = READ_ONCE(iter_info->marks[type]->connector);
+		/* Mark is just getting destroyed or created? */
+		if (!conn)
+			continue;
+		fsid = conn->fsid;
 		if (WARN_ON_ONCE(!fsid.val[0] && !fsid.val[1]))
 			continue;
 		return fsid;
@@ -408,8 +414,12 @@ static int fanotify_handle_event(struct fsnotify_group *group,
 			return 0;
 	}
 
-	if (FAN_GROUP_FLAG(group, FAN_REPORT_FID))
+	if (FAN_GROUP_FLAG(group, FAN_REPORT_FID)) {
 		fsid = fanotify_get_fsid(iter_info);
+		/* Racing with mark destruction or creation? */
+		if (!fsid.val[0] && !fsid.val[1])
+			return 0;
+	}
 
 	event = fanotify_alloc_event(group, inode, mask, data, data_type,
 				     &fsid);
diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c
index 56992b32c6bb..a90bb19dcfa2 100644
--- a/fs/notify/fanotify/fanotify_user.c
+++ b/fs/notify/fanotify/fanotify_user.c
@@ -208,6 +208,7 @@ static int copy_fid_to_user(struct fanotify_event *event, char __user *buf)
 {
 	struct fanotify_event_info_fid info = { };
 	struct file_handle handle = { };
+	unsigned char bounce[FANOTIFY_INLINE_FH_LEN], *fh;
 	size_t fh_len = event->fh_len;
 	size_t len = fanotify_event_info_len(event);
 
@@ -233,7 +234,16 @@ static int copy_fid_to_user(struct fanotify_event *event, char __user *buf)
 
 	buf += sizeof(handle);
 	len -= sizeof(handle);
-	if (copy_to_user(buf, fanotify_event_fh(event), fh_len))
+	/*
+	 * For an inline fh, copy through stack to exclude the copy from
+	 * usercopy hardening protections.
+	 */
+	fh = fanotify_event_fh(event);
+	if (fh_len <= FANOTIFY_INLINE_FH_LEN) {
+		memcpy(bounce, fh, fh_len);
+		fh = bounce;
+	}
+	if (copy_to_user(buf, fh, fh_len))
 		return -EFAULT;
 
 	/* Pad with 0's */