From: Kim B. Heino <Kim.Heino@bluegiga.com>
Date: Fri, 29 Feb 2008 20:26:21 +0000 (-0800)
Subject: [TUN]: Fix RTNL-locking in tun/tap driver
X-Git-Tag: v2.6.25-rc4~2^2~11
X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=401023710d73aaef1191ab4d6a79d39c51add828;p=linux-2.6

[TUN]: Fix RTNL-locking in tun/tap driver

Current tun/tap driver sets also net device's hw address when asked to
change character device's hw address. This is a good idea, but it
misses RTLN-locking, resulting following error message in 2.6.25-rc3's
inetdev_event() function:

RTNL: assertion failed at net/ipv4/devinet.c (1050)

Attached patch fixes this problem.

Signed-off-by: Kim B. Heino <Kim.Heino@bluegiga.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index 038c1ef94d..7b816a0329 100644
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -663,7 +663,11 @@ static int tun_chr_ioctl(struct inode *inode, struct file *file,
 	case SIOCSIFHWADDR:
 	{
 		/* try to set the actual net device's hw address */
-		int ret = dev_set_mac_address(tun->dev, &ifr.ifr_hwaddr);
+		int ret;
+
+		rtnl_lock();
+		ret = dev_set_mac_address(tun->dev, &ifr.ifr_hwaddr);
+		rtnl_unlock();
 
 		if (ret == 0) {
 			/** Set the character device's hardware address. This is used when