From: Amir Goldstein <amir73il@xxxxxxxxx> [ Upstream commit 2f02fd3fa13e51713b630164f8a8e5b42de8283b ] The comments in fanotify_group_event_mask() say: "If the event is on dir/child and this mark doesn't care about events on dir/child, don't send it!" Specifically, mount and filesystem marks do not care about events on child, but they can still specify an ignore mask for those events. For example, a group that has: - A mount mark with mask 0 and ignore_mask FAN_OPEN - An inode mark on a directory with mask FAN_OPEN | FAN_OPEN_EXEC with flag FAN_EVENT_ON_CHILD A child file open for exec would be reported to group with the FAN_OPEN event despite the fact that FAN_OPEN is in ignore mask of mount mark, because the mark iteration loop skips over non-inode marks for events on child when calculating the ignore mask. Move ignore mask calculation to the top of the iteration loop block before excluding marks for events on dir/child. Link: https://lore.kernel.org/r/20200524072441.18258-1-amir73il@xxxxxxxxx Reported-by: Jan Kara <jack@xxxxxxx> Link: https://lore.kernel.org/linux-fsdevel/20200521162443.GA26052@xxxxxxxxxxxxxx/ Fixes: 55bf882c7f13 "fanotify: fix merging marks masks with FAN_ONDIR" Fixes: b469e7e47c8a "fanotify: fix handling of events on child..." Signed-off-by: Amir Goldstein <amir73il@xxxxxxxxx> Signed-off-by: Jan Kara <jack@xxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- fs/notify/fanotify/fanotify.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c index deb13f0a0f7d..d24548ed31b9 100644 --- a/fs/notify/fanotify/fanotify.c +++ b/fs/notify/fanotify/fanotify.c @@ -171,6 +171,10 @@ static u32 fanotify_group_event_mask(struct fsnotify_group *group, if (!fsnotify_iter_should_report_type(iter_info, type)) continue; mark = iter_info->marks[type]; + + /* Apply ignore mask regardless of ISDIR and ON_CHILD flags */ + marks_ignored_mask |= mark->ignored_mask; + /* * If the event is on dir and this mark doesn't care about * events on dir, don't send it! @@ -188,7 +192,6 @@ static u32 fanotify_group_event_mask(struct fsnotify_group *group, continue; marks_mask |= mark->mask; - marks_ignored_mask |= mark->ignored_mask; } test_mask = event_mask & marks_mask & ~marks_ignored_mask; -- 2.25.1
