Module Name: src
Committed By: thorpej
Date: Thu Oct 21 02:34:04 UTC 2021
Modified Files:
src/sys/kern: kern_event.c
src/sys/sys: event.h
Log Message:
Allow the f_touch() filter op to return an error, specifically in
the EVENT_REGISTER case.
To generate a diff of this commit:
cvs rdiff -u -r1.134 -r1.135 src/sys/kern/kern_event.c
cvs rdiff -u -r1.49 -r1.50 src/sys/sys/event.h
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/kern/kern_event.c
diff -u src/sys/kern/kern_event.c:1.134 src/sys/kern/kern_event.c:1.135
--- src/sys/kern/kern_event.c:1.134 Thu Oct 21 01:11:21 2021
+++ src/sys/kern/kern_event.c Thu Oct 21 02:34:03 2021
@@ -1,4 +1,4 @@
-/* $NetBSD: kern_event.c,v 1.134 2021/10/21 01:11:21 thorpej Exp $ */
+/* $NetBSD: kern_event.c,v 1.135 2021/10/21 02:34:03 thorpej Exp $ */
/*-
* Copyright (c) 2008, 2009, 2021 The NetBSD Foundation, Inc.
@@ -63,7 +63,7 @@
#endif /* _KERNEL_OPT */
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: kern_event.c,v 1.134 2021/10/21 01:11:21 thorpej Exp $");
+__KERNEL_RCSID(0, "$NetBSD: kern_event.c,v 1.135 2021/10/21 02:34:03 thorpej Exp $");
#include <sys/param.h>
#include <sys/systm.h>
@@ -116,7 +116,7 @@ static int filt_timer(struct knote *, lo
static int filt_userattach(struct knote *);
static void filt_userdetach(struct knote *);
static int filt_user(struct knote *, long hint);
-static void filt_usertouch(struct knote *, struct kevent *, long type);
+static int filt_usertouch(struct knote *, struct kevent *, long type);
static const struct fileops kqueueops = {
.fo_name = "kqueue",
@@ -476,10 +476,10 @@ filter_event(struct knote *kn, long hint
return rv;
}
-static void
+static int
filter_touch(struct knote *kn, struct kevent *kev, long type)
{
- kn->kn_fop->f_touch(kn, kev, type);
+ return kn->kn_fop->f_touch(kn, kev, type);
}
static kauth_listener_t kqueue_listener;
@@ -1384,7 +1384,7 @@ filt_user(struct knote *kn, long hint)
return hookid;
}
-static void
+static int
filt_usertouch(struct knote *kn, struct kevent *kev, long type)
{
int ffctrl;
@@ -1441,6 +1441,8 @@ filt_usertouch(struct knote *kn, struct
panic("filt_usertouch() - invalid type (%ld)", type);
break;
}
+
+ return 0;
}
/*
@@ -1874,8 +1876,13 @@ kqueue_register(struct kqueue *kq, struc
if (!(kn->kn_fop->f_flags & FILTEROP_ISFD) &&
kn->kn_fop->f_touch != NULL) {
mutex_spin_enter(&kq->kq_lock);
- filter_touch(kn, kev, EVENT_REGISTER);
+ error = filter_touch(kn, kev, EVENT_REGISTER);
mutex_spin_exit(&kq->kq_lock);
+ if (__predict_false(error != 0)) {
+ /* Never a new knote (which would consume newkn). */
+ KASSERT(newkn != NULL);
+ goto doneunlock;
+ }
} else {
kn->kn_sfflags = kev->fflags;
kn->kn_sdata = kev->data;
@@ -1887,7 +1894,7 @@ kqueue_register(struct kqueue *kq, struc
* support events, and the attach routine is
* broken and does not return an error.
*/
-done_ev_add:
+ done_ev_add:
rv = filter_event(kn, 0);
if (rv)
knote_activate(kn);
@@ -1904,7 +1911,7 @@ done_ev_add:
if ((kev->flags & EV_ENABLE)) {
knote_enqueue(kn);
}
-doneunlock:
+ doneunlock:
mutex_exit(&fdp->fd_lock);
done:
rw_exit(&kqueue_filter_lock);
@@ -2197,7 +2204,7 @@ relock:
kn->kn_fop->f_touch != NULL);
/* XXXAD should be got from f_event if !oneshot. */
if (touch) {
- filter_touch(kn, kevp, EVENT_PROCESS);
+ (void)filter_touch(kn, kevp, EVENT_PROCESS);
} else {
*kevp = kn->kn_kevent;
}
Index: src/sys/sys/event.h
diff -u src/sys/sys/event.h:1.49 src/sys/sys/event.h:1.50
--- src/sys/sys/event.h:1.49 Wed Oct 20 03:08:18 2021
+++ src/sys/sys/event.h Thu Oct 21 02:34:04 2021
@@ -1,4 +1,4 @@
-/* $NetBSD: event.h,v 1.49 2021/10/20 03:08:18 thorpej Exp $ */
+/* $NetBSD: event.h,v 1.50 2021/10/21 02:34:04 thorpej Exp $ */
/*-
* Copyright (c) 1999,2000,2001 Jonathan Lemon <jle...@freebsd.org>
@@ -230,7 +230,7 @@ struct filterops {
/* called when knote is DELETEd */
int (*f_event) (struct knote *, long);
/* called when event is triggered */
- void (*f_touch) (struct knote *, struct kevent *, long);
+ int (*f_touch) (struct knote *, struct kevent *, long);
};
/* filterops flags */
