From ee9369a05f5e6e0bcece4556a3e93109d9277071 Mon Sep 17 00:00:00 2001
From: David Ahern <dsa@cumulusnetworks.com>
Date: Thu, 15 Dec 2016 12:07:02 -0800
Subject: [PATCH] ip netns: Reset vrf to default VRF on namespace switch

A vrf is local to a namespace. Drop any VRF association before trying
to exec a command in the new namespace.

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
---
 ip/ip_common.h |  1 +
 ip/ipnetns.c   |  5 +++++
 ip/ipvrf.c     | 14 ++++++++++++++
 3 files changed, 20 insertions(+)

diff --git a/ip/ip_common.h b/ip/ip_common.h
index 28763e81..ab6a8343 100644
--- a/ip/ip_common.h
+++ b/ip/ip_common.h
@@ -58,6 +58,7 @@ int do_tcp_metrics(int argc, char **argv);
 int do_ipnetconf(int argc, char **argv);
 int do_iptoken(int argc, char **argv);
 int do_ipvrf(int argc, char **argv);
+void vrf_reset(void);
 
 int iplink_get(unsigned int flags, char *name, __u32 filt_mask);
 
diff --git a/ip/ipnetns.c b/ip/ipnetns.c
index db9a5417..8201b94a 100644
--- a/ip/ipnetns.c
+++ b/ip/ipnetns.c
@@ -387,6 +387,11 @@ static int netns_exec(int argc, char **argv)
 	if (netns_switch(argv[0]))
 		return -1;
 
+	/* we just changed namespaces. clear any vrf association
+	 * with prior namespace before exec'ing command
+	 */
+	vrf_reset();
+
 	/* ip must return the status of the child,
 	 * but do_cmd() will add a minus to this,
 	 * so let's add another one here to cancel it.
diff --git a/ip/ipvrf.c b/ip/ipvrf.c
index de2ec5c1..dc8364a4 100644
--- a/ip/ipvrf.c
+++ b/ip/ipvrf.c
@@ -277,6 +277,20 @@ static int ipvrf_exec(int argc, char **argv)
 	return -cmd_exec(argv[1], argv + 1, !!batch_mode);
 }
 
+/* reset VRF association of current process to default VRF;
+ * used by netns_exec
+ */
+void vrf_reset(void)
+{
+	char vrf[32];
+
+	if (vrf_identify(getpid(), vrf, sizeof(vrf)) ||
+	    (vrf[0] == '\0'))
+		return;
+
+	vrf_switch("default");
+}
+
 int do_ipvrf(int argc, char **argv)
 {
 	if (argc == 0) {