svn commit: r366623 - head/sys/netinet

[Bjoern A. Zeeb]

Author: bz
Date: Sun Oct 11 00:01:00 2020
New Revision: 366623
URL: https://svnweb.freebsd.org/changeset/base/366623

Log:
  ip_mroute: fix the viftable export sysctl
  
  It seems that in r354857 I got more than one thing wrong.
  Convert the SYSCTL_OPAQUE to a SYSCTL_PROC to properly export the these
  days allocated and not longer static per-vnet viftable array.
  This fixes a problem with netstat -g which would show bogus information
  for the IPv4 Virtual Interface Table.
  
  PR:		246626
  Reported by:	Ozkan KIRIK (ozkan.kirik gmail.com)
  MFC after:	3 days

Modified:
  head/sys/netinet/ip_mroute.c

Modified: head/sys/netinet/ip_mroute.c
==============================================================================
--- head/sys/netinet/ip_mroute.c	Sat Oct 10 21:52:00 2020	(r366622)
+++ head/sys/netinet/ip_mroute.c	Sun Oct 11 00:01:00 2020	(r366623)
@@ -181,13 +181,6 @@ VNET_DEFINE_STATIC(vifi_t, numvifs);
 #define	V_numvifs		VNET(numvifs)
 VNET_DEFINE_STATIC(struct vif *, viftable);
 #define	V_viftable		VNET(viftable)
-/*
- * No one should be able to "query" this before initialisation happened in
- * vnet_mroute_init(), so we should still be fine.
- */
-SYSCTL_OPAQUE(_net_inet_ip, OID_AUTO, viftable, CTLFLAG_VNET | CTLFLAG_RD,
-    &VNET_NAME(viftable), sizeof(*V_viftable) * MAXVIFS, "S,vif[MAXVIFS]",
-    "IPv4 Multicast Interfaces (struct vif[MAXVIFS], netinet/ip_mroute.h)");
 
 static struct mtx vif_mtx;
 #define	VIF_LOCK()		mtx_lock(&vif_mtx)
@@ -2805,6 +2798,30 @@ static SYSCTL_NODE(_net_inet_ip, OID_AUTO, mfctable,
     CTLFLAG_RD | CTLFLAG_MPSAFE, sysctl_mfctable,
     "IPv4 Multicast Forwarding Table "
     "(struct *mfc[mfchashsize], netinet/ip_mroute.h)");
+
+static int
+sysctl_viflist(SYSCTL_HANDLER_ARGS)
+{
+	int error;
+
+	if (req->newptr)
+		return (EPERM);
+	if (V_viftable == NULL)		/* XXX unlocked */
+		return (0);
+	error = sysctl_wire_old_buffer(req, sizeof(*V_viftable) * MAXVIFS);
+	if (error)
+		return (error);
+
+	VIF_LOCK();
+	error = SYSCTL_OUT(req, V_viftable, sizeof(*V_viftable) * MAXVIFS);
+	VIF_UNLOCK();
+	return (error);
+}
+
+SYSCTL_PROC(_net_inet_ip, OID_AUTO, viftable,
+    CTLTYPE_OPAQUE | CTLFLAG_VNET | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0,
+    sysctl_viflist, "S,vif[MAXVIFS]",
+    "IPv4 Multicast Interfaces (struct vif[MAXVIFS], netinet/ip_mroute.h)");
 
 static void
 vnet_mroute_init(const void *unused __unused)