On Tue, 7 Jul 2015 15:55:21 +0100 Julien Grall <julien.grall@xxxxxxxxxx> wrote: > The commit efb6de9b4ba0092b2c55f6a52d16294a8a698edd "netfilter: bridge: > forward IPv6 fragmented packets" introduced a new function > br_validate_ipv6 which take a reference on the inet6 device. Although, > the reference is not released at the end. > > This will result to the impossibility to destroy any netdevice using > ipv6 and bridge. > > It's possible to directly retrieve the inet6 device without taking a > reference as all netfilter hooks are protected by rcu_read_lock via > nf_hook_slow. > > Spotted while trying to destroy a Xen guest on the upstream Linux: > "unregister_netdevice: waiting for vif1.0 to become free. Usage count = 1" > > Signed-off-by: Julien Grall <julien.grall@xxxxxxxxxx> > Cc: Bernhard Thaler <bernhard.thaler@xxxxxxxx> > Cc: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx> > Cc: fw@xxxxxxxxx > Cc: ian.campbell@xxxxxxxxxx > Cc: wei.liu2@xxxxxxxxxx > Cc: Bob Liu <bob.liu@xxxxxxxxxx> > > --- > Note that it's impossible to create new guest after this message. > I'm not sure if it's normal. > > Changes in v2: > - Don't take a reference to inet6. > - This was "net/bridge: Add missing in6_dev_put in > br_validate_ipv6" [0] > > [0] https://lkml.org/lkml/2015/7/3/443 > --- > net/bridge/br_netfilter_ipv6.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) I like this simple solution Acked-by: Stephen Hemminger <stephen@xxxxxxxxxxxxxxxxxx> -- To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
