Hello Amir! I was looking into backporting of commit 55bf882c7f13dd "fanotify: fix merging marks masks with FAN_ONDIR" and realized one oddity in fanotify_group_event_mask(). The thing is: Even if the mark mask is such that current event shouldn't trigger on the mark, we still have to take mark's ignore mask into account. The most realistic example that would demonstrate the issue that comes to my mind is: mount mark watching for FAN_OPEN | FAN_ONDIR. inode mark on a directory with mask == 0 and ignore_mask == FAN_OPEN. I'd expect the group will not get any event for opening the dir but the code in fanotify_group_event_mask() would not prevent event generation. Now as I've tested the event currently actually does not get generated because there is a rough test in send_to_group() that actually finds out that there shouldn't be anything to report and so fanotify handler is actually never called in such case. But I don't think it's good to have an inconsistent test in fanotify_group_event_mask(). What do you think? Honza -- Jan Kara <jack@xxxxxxxx> SUSE Labs, CR
