On Tue, 10 May 2011 11:05:40 -0700 Noah Meyerhans <noahm@xxxxxxxxxx> wrote: > On Tue, May 10, 2011 at 01:42:49PM +0100, Ben Hutchings wrote: > > > > This is pretty weird. Debian version 2.6.38-3 has a few bridging > > > > changes from stable 2.6.38.3 and 2.6.38.4, but they don't look like they > > > > would cause this. > > > > > > I have apparently filed the bug against the wrong version of Debian's > > > kernel. 2.6.38-3 is not affected, and works as expected. The change > > > was introduced in -4. That may have been clear from the report itself, > > > but the report was filed against -3. I've fixed that in the BTS. > > > > I gathered that, and then made the same mistake in writing the above! > > The version with the regression, 2.6.38-4, includes the changes from > > stable 2.6.38.3 and 2.6.38.4 > > With a little help from git bisect, I've tracked this regression down to > the following commit to the stable-2.6.38.y tree: > > commit 5f1c356a3fadc0c19922d660da723b79bcc9aad7 > Author: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx> > Date: Fri Mar 18 05:27:28 2011 +0000 > > bridge: Reset IPCB when entering IP stack on NF_FORWARD > > [ Upstream commit 6b1e960fdbd75dcd9bcc3ba5ff8898ff1ad30b6e ] > > Whenever we enter the IP stack proper from bridge netfilter we > need to ensure that the skb is in a form the IP stack expects > it to be in. > > The entry point on NF_FORWARD did not meet the requirements of > the IP stack, therefore leading to potential crashes/panics. > > This patch fixes the problem. > > Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx> > Acked-by: Stephen Hemminger <shemminger@xxxxxxxxxx> > Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> > Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx> > > The diff is > diff --git a/net/bridge/br_netfilter.c b/net/bridge/br_netfilter.c > index 4b5b66d..49d50ea 100644 > --- a/net/bridge/br_netfilter.c > +++ b/net/bridge/br_netfilter.c > @@ -741,6 +741,9 @@ static unsigned int br_nf_forward_ip(unsigned int > hook, struct sk_buff *skb, > nf_bridge->mask |= BRNF_PKT_TYPE; > } > > + if (br_parse_ip_options(skb)) > + return NF_DROP; > + > /* The physdev module checks on this */ > nf_bridge->mask |= BRNF_BRIDGED; > nf_bridge->physoutdev = skb->dev; > > If I revert this change, network connectivity functions as expected for > the VMs on this host. > > I don't know enough about this change or the problem it was supposed to > solve to be able to guess about what's going wrong. > > noah > There were two more follow on commits in stable related to this. I recommend merging 2.6.38.6 which includes these. -- _______________________________________________ Bridge mailing list Bridge@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/bridge
