svn commit: r367381 - stable/12/sys/netinet

[Bjoern A. Zeeb]

Author: bz
Date: Thu Nov  5 13:43:06 2020
New Revision: 367381
URL: https://svnweb.freebsd.org/changeset/base/367381

Log:
  MFC r366623:
  
   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

Modified:
  stable/12/sys/netinet/ip_mroute.c
Directory Properties:
  stable/12/   (props changed)

Modified: stable/12/sys/netinet/ip_mroute.c
==============================================================================
--- stable/12/sys/netinet/ip_mroute.c	Thu Nov  5 13:38:26 2020	(r367380)
+++ stable/12/sys/netinet/ip_mroute.c	Thu Nov  5 13:43:06 2020	(r367381)
@@ -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)
@@ -2803,6 +2796,30 @@ out_locked:
 static SYSCTL_NODE(_net_inet_ip, OID_AUTO, mfctable, CTLFLAG_RD,
     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)