[src/trunk]: src/sys/net add lock for sclist to exclude ifconfig gifX add/del...

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

details:   https://anonhg.NetBSD.org/src/rev/368c7ada9524
branches:  trunk
changeset: 826664:368c7ada9524
user:      knakahara <knakahara%NetBSD.org@localhost>
date:      Thu Sep 21 09:46:14 2017 +0000

description:
add lock for sclist to exclude ifconfig gifX add/delete and ifconfig gifX tunnel

diffstat:

 sys/net/if_gif.c |  27 ++++++++++++++++++++-------
 1 files changed, 20 insertions(+), 7 deletions(-)

diffs (90 lines):

diff -r f2a071e1ccb6 -r 368c7ada9524 sys/net/if_gif.c
--- a/sys/net/if_gif.c  Thu Sep 21 09:42:03 2017 +0000
+++ b/sys/net/if_gif.c  Thu Sep 21 09:46:14 2017 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: if_gif.c,v 1.129 2017/09/21 09:42:03 knakahara Exp $   */
+/*     $NetBSD: if_gif.c,v 1.130 2017/09/21 09:46:14 knakahara Exp $   */
 /*     $KAME: if_gif.c,v 1.76 2001/08/20 02:01:02 kjc Exp $    */
 
 /*
@@ -31,7 +31,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: if_gif.c,v 1.129 2017/09/21 09:42:03 knakahara Exp $");
+__KERNEL_RCSID(0, "$NetBSD: if_gif.c,v 1.130 2017/09/21 09:46:14 knakahara Exp $");
 
 #ifdef _KERNEL_OPT
 #include "opt_inet.h"
@@ -96,7 +96,11 @@
 /*
  * gif global variable definitions
  */
-static LIST_HEAD(, gif_softc) gif_softc_list;
+LIST_HEAD(gif_sclist, gif_softc);
+static struct {
+       struct gif_sclist list;
+       kmutex_t lock;
+} gif_softcs __cacheline_aligned;
 
 static void    gif_ro_init_pc(void *, void *, struct cpu_info *);
 static void    gif_ro_fini_pc(void *, void *, struct cpu_info *);
@@ -208,7 +212,8 @@
 gifinit(void)
 {
 
-       LIST_INIT(&gif_softc_list);
+       mutex_init(&gif_softcs.lock, MUTEX_DEFAULT, IPL_NONE);
+       LIST_INIT(&gif_softcs.list);
        if_clone_attach(&gif_cloner);
 
        gif_sysctl_setup();
@@ -219,8 +224,11 @@
 {
        int error = 0;
 
-       if (!LIST_EMPTY(&gif_softc_list))
+       mutex_enter(&gif_softcs.lock);
+       if (!LIST_EMPTY(&gif_softcs.list)) {
+               mutex_exit(&gif_softcs.lock);
                error = EBUSY;
+       }
 
        if (error == 0) {
                if_clone_detach(&gif_cloner);
@@ -244,7 +252,9 @@
        sc->gif_ro_percpu = percpu_alloc(sizeof(struct gif_ro));
        percpu_foreach(sc->gif_ro_percpu, gif_ro_init_pc, NULL);
 
-       LIST_INSERT_HEAD(&gif_softc_list, sc, gif_list);
+       mutex_enter(&gif_softcs.lock);
+       LIST_INSERT_HEAD(&gif_softcs.list, sc, gif_list);
+       mutex_exit(&gif_softcs.lock);
        return (0);
 }
 
@@ -994,7 +1004,8 @@
                return error;
        }
 
-       LIST_FOREACH(sc2, &gif_softc_list, gif_list) {
+       mutex_enter(&gif_softcs.lock);
+       LIST_FOREACH(sc2, &gif_softcs.list, gif_list) {
                if (sc2 == sc)
                        continue;
                if (!sc2->gif_pdst || !sc2->gif_psrc)
@@ -1003,12 +1014,14 @@
                if (sockaddr_cmp(sc2->gif_pdst, dst) == 0 &&
                    sockaddr_cmp(sc2->gif_psrc, src) == 0) {
                        /* continue to use the old configureation. */
+                       mutex_exit(&gif_softcs.lock);
                        error =  EADDRNOTAVAIL;
                        goto out;
                }
 
                /* XXX both end must be valid? (I mean, not 0.0.0.0) */
        }
+       mutex_exit(&gif_softcs.lock);
 
        nsrc = sockaddr_dup(src, M_WAITOK);
        ndst = sockaddr_dup(dst, M_WAITOK);