diff options
| author | David Woodhouse <dwmw2@infradead.org> | 2011-10-24 21:25:21 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2011-11-11 09:35:47 -0800 |
| commit | 5c2433cdc72a03446184e2f898be3b05095b5ed0 (patch) | |
| tree | b4532445ad6d2b5ceaf9eb44409580b97effecb4 /net | |
| parent | 7b59e3e29e1a28ad40892dd2115175e2702f1153 (diff) | |
caif: Fix BUG() with network namespaces
commit 08613e4626c06ca408fc55071f6aedee36986a87 upstream.
The caif code will register its own pernet_operations, and then register
a netdevice_notifier. Each time the netdevice_notifier is triggered,
it'll do some stuff... including a lookup of its own pernet stuff with
net_generic().
If the net_generic() call ever returns NULL, the caif code will BUG().
That doesn't seem *so* unreasonable, I suppose — it does seem like it
should never happen.
However, it *does* happen. When we clone a network namespace,
setup_net() runs through all the pernet_operations one at a time. It
gets to loopback before it gets to caif. And loopback_net_init()
registers a netdevice... while caif hasn't been initialised. So the caif
netdevice notifier triggers, and immediately goes BUG().
We could imagine a complex and overengineered solution to this generic
class of problems, but this patch takes the simple approach. It just
makes caif_device_notify() *not* go looking for its pernet data
structures if the device it's being notified about isn't a caif device
in the first place.
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Acked-by: Sjur Brændeland <sjur.brandeland@stericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'net')
| -rw-r--r-- | net/caif/caif_dev.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/net/caif/caif_dev.c b/net/caif/caif_dev.c index 682c0fedf360..dbdaa95b8005 100644 --- a/net/caif/caif_dev.c +++ b/net/caif/caif_dev.c @@ -209,8 +209,7 @@ static int caif_device_notify(struct notifier_block *me, unsigned long what, enum cfcnfg_phy_preference pref; enum cfcnfg_phy_type phy_type; struct cfcnfg *cfg; - struct caif_device_entry_list *caifdevs = - caif_device_list(dev_net(dev)); + struct caif_device_entry_list *caifdevs; if (dev->type != ARPHRD_CAIF) return 0; @@ -219,6 +218,8 @@ static int caif_device_notify(struct notifier_block *me, unsigned long what, if (cfg == NULL) return 0; + caifdevs = caif_device_list(dev_net(dev)); + switch (what) { case NETDEV_REGISTER: caifd = caif_device_alloc(dev); |