On Thu, May 3, 2018 at 6:58 PM, Eric Dumazet <eric.duma...@gmail.com> wrote: > > > On 05/03/2018 05:33 PM, Alexander Duyck wrote: >> From: Alexander Duyck <alexander.h.du...@intel.com> >> >> This patch makes it so that if a destructor is not present we avoid trying >> to update the skb socket or any reference counting that would be associated >> with the NULL socket and/or descriptor. By doing this we can support >> traffic coming from another namespace without any issues. >> >> Signed-off-by: Alexander Duyck <alexander.h.du...@intel.com> >> --- >> net/ipv4/udp_offload.c | 19 +++++++++++++------ >> 1 file changed, 13 insertions(+), 6 deletions(-) >> >> diff --git a/net/ipv4/udp_offload.c b/net/ipv4/udp_offload.c >> index fd94bbb369b2..52760660d674 100644 >> --- a/net/ipv4/udp_offload.c >> +++ b/net/ipv4/udp_offload.c >> @@ -195,6 +195,7 @@ struct sk_buff *__udp_gso_segment(struct sk_buff >> *gso_skb, >> unsigned int sum_truesize = 0; >> struct udphdr *uh; >> unsigned int mss; >> + bool copy_dtor; >> __sum16 check; >> __be16 newlen; >> >> @@ -208,12 +209,14 @@ struct sk_buff *__udp_gso_segment(struct sk_buff >> *gso_skb, >> skb_pull(gso_skb, sizeof(*uh)); >> >> /* clear destructor to avoid skb_segment assigning it to tail */ >> - WARN_ON_ONCE(gso_skb->destructor != sock_wfree); >> + copy_dtor = gso_skb->destructor == sock_wfree; >> + WARN_ON_ONCE(gso_skb->destructor && !copy_dtor); > > Why not simply clear gso_skb->destructor only if copy_dtor is true ? > > Then we can get rid of this WARN_ON_ONCE()
Sounds good. I think I had code similar to that in an earlier version of this patch, but when I started breaking things up I got rid of this code until I realized I needed it due to a kernel panic triggered by running the offload over a VXLAN from another namespace. Thanks. - Alex
