[src/netbsd-1-4]: src/sys/netinet Apply patch (partially revision 1.63, reque...

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

details:   https://anonhg.NetBSD.org/src/rev/8e0537ca6966
branches:  netbsd-1-4
changeset: 470708:8e0537ca6966
user:      he <he%NetBSD.org@localhost>
date:      Sun Jul 02 21:45:32 2000 +0000

description:
Apply patch (partially revision 1.63, requested by sommerfeld):
  Protect arp table handling with splnet() to avoid interrupt races
  when ip_flow is in use.  Fixes PR#10351.

diffstat:

 sys/netinet/if_arp.c |  44 ++++++++++++++++++++++++++++++++------------
 1 files changed, 32 insertions(+), 12 deletions(-)

diffs (104 lines):

diff -r 3015aaa568c8 -r 8e0537ca6966 sys/netinet/if_arp.c
--- a/sys/netinet/if_arp.c      Sun Jul 02 21:39:19 2000 +0000
+++ b/sys/netinet/if_arp.c      Sun Jul 02 21:45:32 2000 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: if_arp.c,v 1.56.2.3 1999/06/20 19:20:33 perry Exp $    */
+/*     $NetBSD: if_arp.c,v 1.56.2.4 2000/07/02 21:45:32 he Exp $       */
 
 /*-
  * Copyright (c) 1998 The NetBSD Foundation, Inc.
@@ -223,10 +223,15 @@
        register struct rtentry *rt;
        struct sockaddr *sa;
 {
-       register struct sockaddr *gate = rt->rt_gateway;
-       register struct llinfo_arp *la = (struct llinfo_arp *)rt->rt_llinfo;
+       register struct sockaddr *gate;
+       register struct llinfo_arp *la;
        static struct sockaddr_dl null_sdl = {sizeof(null_sdl), AF_LINK};
        size_t allocsize;
+       int s;
+
+       s = splnet();
+       gate = rt->rt_gateway;
+       la = (struct llinfo_arp *)rt->rt_llinfo;
 
        if (!arpinit_done) {
                arpinit_done = 1;
@@ -239,8 +244,11 @@
                }
                timeout(arptimer, (caddr_t)0, hz);
        }
-       if (rt->rt_flags & RTF_GATEWAY)
+       if (rt->rt_flags & RTF_GATEWAY) {
+               splx(s);          
                return;
+       }
+
        switch (req) {
 
        case RTM_ADD:
@@ -344,6 +352,7 @@
                        m_freem(la->la_hold);
                Free((caddr_t)la);
        }
+       splx(s);
 }
 
 /*
@@ -403,6 +412,8 @@
 {
        register struct llinfo_arp *la;
        struct sockaddr_dl *sdl;
+       struct mbuf *om;
+       int s;
 
        if (rt)
                la = (struct llinfo_arp *)rt->rt_llinfo;
@@ -431,9 +442,14 @@
         * response yet.  Replace the held mbuf with this
         * latest one.
         */
-       if (la->la_hold)
-               m_freem(la->la_hold);
+       s = splnet();
+       om = la->la_hold;
        la->la_hold = m;
+       splx(s);
+
+       if (om)
+               m_freem(om);
+
        /*
         * Re-send the ARP request when appropriate.
         */
@@ -524,7 +540,8 @@
        struct sockaddr_dl *sdl;
        struct sockaddr sa;
        struct in_addr isaddr, itaddr, myaddr;
-       int op;
+       struct mbuf *om;
+       int op, s;
 
        ah = mtod(m, struct arphdr *);
        op = ntohs(ah->ar_op);
@@ -660,11 +677,14 @@
                        rt->rt_expire = time.tv_sec + arpt_keep;
                rt->rt_flags &= ~RTF_REJECT;
                la->la_asked = 0;
-               if (la->la_hold) {
-                       (*ifp->if_output)(ifp, la->la_hold,
-                               rt_key(rt), rt);
-                       la->la_hold = 0;
-               }
+
+               s = splnet();
+               om = la->la_hold;
+               la->la_hold = 0;
+               splx(s);
+
+               if (om)
+                       (*ifp->if_output)(ifp, om, rt_key(rt), rt);
        }
 reply:
        if (op != ARPOP_REQUEST) {