From 0cc746f19352979b65a3652149e4f6bd21c0104c Mon Sep 17 00:00:00 2001
From: Robert Wing <rew@FreeBSD.org>
Date: Tue, 2 Mar 2021 14:19:22 -0900
Subject: [PATCH] filt_fsevent: only record interested events

Respect filter-specific flags for the EVFILT_FS filter.

When a kevent is registered with the EVFILT_FS filter, it is always
triggered when an EVFILT_FS event occurs, regardless of the
filter-specific flags used. Fix that.

Reviewed by:	kib
Differential Revision:	https://reviews.freebsd.org/D28974
---
 sys/kern/vfs_subr.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/sys/kern/vfs_subr.c b/sys/kern/vfs_subr.c
index 3f7dae762de0..c4772f691397 100644
--- a/sys/kern/vfs_subr.c
+++ b/sys/kern/vfs_subr.c
@@ -6016,7 +6016,8 @@ static int
 filt_fsevent(struct knote *kn, long hint)
 {
 
-	kn->kn_fflags |= hint;
+	kn->kn_fflags |= kn->kn_sfflags & hint;
+
 	return (kn->kn_fflags != 0);
 }