From 7f10f9404abc9e95998ead236180a2e5e7de1f80 Mon Sep 17 00:00:00 2001
From: Guillaume Nault <g.nault@alphalink.fr>
Date: Mon, 28 Apr 2014 21:13:41 +0200
Subject: [PATCH] net-snmp: unshare file descriptors namespace

Use unshare(CLONE_FILES) to create a local file descriptors namespace
for the SNMP thread. This is similar to what was done in bf5340
'net-snmp: run snmp in "special" thread', but without calling clone()
directly. So the net-snmp plugin keeps running in a regular pthread.

Signed-off-by: Guillaume Nault <g.nault@alphalink.fr>
---
 accel-pppd/extra/net-snmp/agent.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/accel-pppd/extra/net-snmp/agent.c b/accel-pppd/extra/net-snmp/agent.c
index cfeb763..9f8b1a7 100644
--- a/accel-pppd/extra/net-snmp/agent.c
+++ b/accel-pppd/extra/net-snmp/agent.c
@@ -1,5 +1,8 @@
+#include <errno.h>
 #include <pthread.h>
+#include <sched.h>
 #include <signal.h>
+#include <string.h>
 
 #include <net-snmp/net-snmp-config.h>
 #include <net-snmp/net-snmp-includes.h>
@@ -80,6 +83,14 @@ static void *snmp_thread(void *a)
 	sigdelset(&set, 32);
 	pthread_sigmask(SIG_BLOCK, &set, NULL);
 
+	if (unshare(CLONE_FILES) < 0) {
+		log_error("net-snmp: impossible to start SNMP thread:"
+			  " unshare(CLONE_FILES) failed (%s)\n",
+			  strerror(errno));
+
+		return NULL;
+	}
+
 	snmp_register_callback(SNMP_CALLBACK_LIBRARY, SNMP_CALLBACK_LOGGING, agent_log, NULL);
   snmp_disable_log();
 	snmp_enable_calllog();
-- 
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