From 9edb74cc6ccb3a893c3d40727b7003c3c16f85a0 Mon Sep 17 00:00:00 2001 From: David S. Miller Date: Thu, 24 Apr 2008 03:44:43 -0700 Subject: tun: Multicast handling in tun_chr_ioctl() needs proper locking. Since these operations don't go through the normal device calls, we have to ensure we synchronize with those paths. Noticed by Alan Cox. Signed-off-by: David S. Miller --- drivers/net/tun.c | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'drivers') diff --git a/drivers/net/tun.c b/drivers/net/tun.c index d8b1ba15aa6f..0ce07a339c7e 100644 --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -741,7 +741,12 @@ static int tun_chr_ioctl(struct inode *inode, struct file *file, case SIOCADDMULTI: /** Add the specified group to the character device's multicast filter * list. */ + rtnl_lock(); + netif_tx_lock_bh(tun->dev); add_multi(tun->chr_filter, ifr.ifr_hwaddr.sa_data); + netif_tx_unlock_bh(tun->dev); + rtnl_unlock(); + DBG(KERN_DEBUG "%s: add multi: %s\n", tun->dev->name, print_mac(mac, ifr.ifr_hwaddr.sa_data)); return 0; @@ -749,7 +754,12 @@ static int tun_chr_ioctl(struct inode *inode, struct file *file, case SIOCDELMULTI: /** Remove the specified group from the character device's multicast * filter list. */ + rtnl_lock(); + netif_tx_lock_bh(tun->dev); del_multi(tun->chr_filter, ifr.ifr_hwaddr.sa_data); + netif_tx_unlock_bh(tun->dev); + rtnl_unlock(); + DBG(KERN_DEBUG "%s: del multi: %s\n", tun->dev->name, print_mac(mac, ifr.ifr_hwaddr.sa_data)); return 0; -- cgit v1.2.3