| Message ID | 1372198812-19967-1-git-send-email-kamal@canonical.com |
|---|---|
| State | New |
| Headers | show |
diff --git a/drivers/net/tun.c b/drivers/net/tun.c index 522dc0a..2129cf90 100644 --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -1585,6 +1585,10 @@ static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr) else return -EINVAL; + if (!!(ifr->ifr_flags & IFF_MULTI_QUEUE) != + !!(tun->flags & TUN_TAP_MQ)) + return -EINVAL; + if (tun_not_capable(tun)) return -EPERM; err = security_tun_dev_open(tun->security);
This is a note to let you know that I have just added a patch titled tuntap: forbid changing mq flag for persistent device to the linux-3.8.y-queue branch of the 3.8.y.z extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.8.y-queue This patch is scheduled to be released in version 3.8.13.4. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.8.y.z tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Kamal ------ From 8adb101d98a6b50cc9a14aa167d21bbeb585a921 Mon Sep 17 00:00:00 2001 From: Jason Wang <jasowang@redhat.com> Date: Tue, 28 May 2013 18:32:11 +0000 Subject: tuntap: forbid changing mq flag for persistent device [ Upstream commit 8e6d91ae0917bf934ed86411148f79d904728d51 ] We currently allow changing the mq flag (IFF_MULTI_QUEUE) for a persistent device. This will result a mismatch between the number the queues in netdev and tuntap. This is because we only allocate a 1q netdevice when IFF_MULTI_QUEUE was not specified, so when we set the IFF_MULTI_QUEUE and try to attach more queues later, netif_set_real_num_tx_queues() may fail which result a single queue netdevice with multiple sockets attached. Solve this by disallowing changing the mq flag for persistent device. Bug was introduced by commit edfb6a148ce62e5e19354a1dcd9a34e00815c2a1 (tuntap: reduce memory using of queues). Reported-by: Sriram Narasimhan <sriram.narasimhan@hp.com> Cc: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Jason Wang <jasowang@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Kamal Mostafa <kamal@canonical.com> --- drivers/net/tun.c | 4 ++++ 1 file changed, 4 insertions(+) -- 1.8.1.2