[src/trunk]: src/sys/rump/librump/rumpkern rump_component_init() is called re...

[chs <chs%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/5447ce1c86e6
branches:  trunk
changeset: 949838:5447ce1c86e6
user:      chs <chs%NetBSD.org@localhost>
date:      Sun Jan 17 22:32:25 2021 +0000

description:
rump_component_init() is called recursively, so LIST_FOREACH_SAFE is not
actually safe, since the recursive calls can result in elements other than
the current element being removed from the list.  instead use an explicit
marker element to do safe list traversal.

diffstat:

 sys/rump/librump/rumpkern/rump.c |  16 ++++++++++++----
 1 files changed, 12 insertions(+), 4 deletions(-)

diffs (43 lines):

diff -r 19b1c7a904dd -r 5447ce1c86e6 sys/rump/librump/rumpkern/rump.c
--- a/sys/rump/librump/rumpkern/rump.c  Sun Jan 17 21:56:20 2021 +0000
+++ b/sys/rump/librump/rumpkern/rump.c  Sun Jan 17 22:32:25 2021 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: rump.c,v 1.352 2021/01/16 23:50:49 chs Exp $   */
+/*     $NetBSD: rump.c,v 1.353 2021/01/17 22:32:25 chs Exp $   */
 
 /*
  * Copyright (c) 2007-2011 Antti Kantee.  All Rights Reserved.
@@ -26,7 +26,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: rump.c,v 1.352 2021/01/16 23:50:49 chs Exp $");
+__KERNEL_RCSID(0, "$NetBSD: rump.c,v 1.353 2021/01/17 22:32:25 chs Exp $");
 
 #include <sys/systm.h>
 #define ELFSIZE ARCH_ELFSIZE
@@ -605,14 +605,22 @@
 void
 rump_component_init(enum rump_component_type type)
 {
-       struct rump_component *rc, *rc_safe;
+       struct rump_component *rc, *rc_next, rc_marker;
 
        KASSERT(curlwp == bootlwp);
        KASSERT(!compinited[type]);
-       LIST_FOREACH_SAFE(rc, &rchead, rc_entries, rc_safe) {
+
+       rc_marker.rc_type = RUMP_COMPONENT_MAX;
+       rc_marker.rc_init = NULL;
+       for (rc = LIST_FIRST(&rchead); rc != NULL; rc = rc_next) {
                if (rc->rc_type == type) {
+                       LIST_INSERT_AFTER(rc, &rc_marker, rc_entries);
                        rc->rc_init();
                        LIST_REMOVE(rc, rc_entries);
+                       rc_next = LIST_NEXT(&rc_marker, rc_entries);
+                       LIST_REMOVE(&rc_marker, rc_entries);
+               } else {
+                       rc_next = LIST_NEXT(rc, rc_entries);
                }
        }
        compinited[type] = 1;