We attach queue 0 after registering netdevice currently. This leads to call
netif_set_real_num_{tx|rx}_queues() after registering the netdevice. Since we
allow tun/tap has a maximum of 1024 queues, this may lead a huge number of
uevents to be injected to userspace since we create 2048 kobjects and then
remove 2046. Solve this problem by attaching queue 0 and set the real number of
queues before registering netdevice.
Reported-by: Jiri Slaby <jsl...@suse.cz>
Tested-by: Jiri Slaby <jsl...@suse.cz>
Signed-off-by: Jason Wang <jasow...@redhat.com>
---
drivers/net/tun.c | 11 +++++------
1 files changed, 5 insertions(+), 6 deletions(-)
diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index b44d7b7..cc3f878 100644
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -492,9 +492,6 @@ static int tun_attach(struct tun_struct *tun, struct file
*file)
tun_set_real_num_queues(tun);
- if (tun->numqueues == 1)
- netif_carrier_on(tun->dev);
-
/* device is allowed to go away first, so no need to hold extra
* refcnt.
*/
@@ -1611,6 +1608,10 @@ static int tun_set_iff(struct net *net, struct file
*file, struct ifreq *ifr)
TUN_USER_FEATURES;
dev->features = dev->hw_features;
+ err = tun_attach(tun, file);
+ if (err < 0)
+ goto err_free_dev;
+
err = register_netdevice(tun->dev);
if (err < 0)
goto err_free_dev;
@@ -1620,9 +1621,7 @@ static int tun_set_iff(struct net *net, struct file
*file, struct ifreq *ifr)
device_create_file(&tun->dev->dev, &dev_attr_group))
pr_err("Failed to create tun sysfs files\n");
- err = tun_attach(tun, file);
- if (err < 0)
- goto err_free_dev;
+ netif_carrier_on(tun->dev);
}
tun_debug(KERN_INFO, tun, "tun_set_iff\n");
--
1.7.1
--
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