In a group with flag FAN_REPORT_DIR_FID, when adding an inode mark with
FAN_EVENT_ON_CHILD, events on non-directory children are reported with
the fid of the parent.
When adding a filesystem or mount mark or mark on a non-dir inode, we
want to report events that are "possible on child" (e.g. open/close)
also with fid of the parent, as if the victim inode's parent is
interested in events "on child".
Some events, currently only FAN_MOVE_SELF, should be reported to a
sb/mount/non-dir mark with parent fid even though they are not
reported to a watching parent.
To get the desired behavior we set the flag FAN_EVENT_ON_CHILD on
all the sb/mount/non-dir mark masks in a group with FAN_REPORT_DIR_FID.
Signed-off-by: Amir Goldstein <amir73il@xxxxxxxxx>
---
fs/notify/fanotify/fanotify.c | 3 +--
fs/notify/fanotify/fanotify_user.c | 7 +++++++
2 files changed, 8 insertions(+), 2 deletions(-)
diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c
index 23fb1bfb6945..c45d65fa8d1d 100644
--- a/fs/notify/fanotify/fanotify.c
+++ b/fs/notify/fanotify/fanotify.c
@@ -255,8 +255,7 @@ static u32 fanotify_group_event_mask(struct fsnotify_group *group,
*/
if (event_mask & FS_EVENT_ON_CHILD &&
type != FSNOTIFY_OBJ_TYPE_CHILD &&
- (type != FSNOTIFY_OBJ_TYPE_INODE ||
- !(mark->mask & FS_EVENT_ON_CHILD)))
+ !(mark->mask & FS_EVENT_ON_CHILD))
continue;
marks_mask |= mark->mask;
diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c
index fe2c25e26753..20bb1c52b1cd 100644
--- a/fs/notify/fanotify/fanotify_user.c
+++ b/fs/notify/fanotify/fanotify_user.c
@@ -1213,6 +1213,13 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask,
if (mnt || !S_ISDIR(inode->i_mode)) {
mask &= ~FAN_EVENT_ON_CHILD;
umask = FAN_EVENT_ON_CHILD;
+ /*
+ * If group needs to report parent fid, register for getting
+ * events with parent/name info for non-directory.
+ */
+ if ((fid_mode & FAN_REPORT_DIR_FID) &&
+ (flags & FAN_MARK_ADD) && !ignored)
+ mask |= FAN_EVENT_ON_CHILD;
}
/* create/update an inode mark */
--
2.17.1
