Module Name: src
Committed By: drochner
Date: Fri Sep 10 10:23:46 UTC 2010
Modified Files:
src/sys/kern: kern_event.c
Log Message:
make list traversing in knote() safe against removal of the entry
while the loop body is executed -- at least in the EVFILT_PROC / exit
case a race condition exists which can cause this
fixes a panic triggered eg by tests/kernel/kqueue/proc1
To generate a diff of this commit:
cvs rdiff -u -r1.70 -r1.71 src/sys/kern/kern_event.c
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:1.70 src/sys/kern/kern_event.c:1.71
--- src/sys/kern/kern_event.c:1.70 Thu Jul 1 02:38:30 2010
+++ src/sys/kern/kern_event.c Fri Sep 10 10:23:46 2010
@@ -1,4 +1,4 @@
-/* $NetBSD: kern_event.c,v 1.70 2010/07/01 02:38:30 rmind Exp $ */
+/* $NetBSD: kern_event.c,v 1.71 2010/09/10 10:23:46 drochner Exp $ */
/*-
* Copyright (c) 2008, 2009 The NetBSD Foundation, Inc.
@@ -58,7 +58,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: kern_event.c,v 1.70 2010/07/01 02:38:30 rmind Exp $");
+__KERNEL_RCSID(0, "$NetBSD: kern_event.c,v 1.71 2010/09/10 10:23:46 drochner Exp $");
#include <sys/param.h>
#include <sys/systm.h>
@@ -1460,9 +1460,9 @@
void
knote(struct klist *list, long hint)
{
- struct knote *kn;
+ struct knote *kn, *tmpkn;
- SLIST_FOREACH(kn, list, kn_selnext) {
+ SLIST_FOREACH_SAFE(kn, list, kn_selnext, tmpkn) {
if ((*kn->kn_fop->f_event)(kn, hint))
knote_activate(kn);
}
