| Message ID | 1439913296-6026-1-git-send-email-dsa@cumulusnetworks.com |
|---|---|
| State | Awaiting Upstream, archived |
| Delegated to: | David Miller |
| Headers | show |
> On Aug 18, 2015, at 6:54 PM, David Ahern <dsa@cumulusnetworks.com> wrote: > > Directs route lookups to VRF table. Compiles out if NET_VRF is not > enabled. With this patch able to successfully bring up ipsec tunnels > in VRFs, even with duplicate network configuration (IPv4 tested). > > Signed-off-by: David Ahern <dsa@cumulusnetworks.com> > --- > net/ipv4/xfrm4_policy.c | 7 +++++-- > net/ipv6/xfrm6_policy.c | 7 +++++-- > 2 files changed, 10 insertions(+), 4 deletions(-) I think you should use the new vrf_master_index() helper that acquires rcu because it looks possible to call ->decode_session() without rcu read lock, e.g. in the hold_timer function xfrm_policy_queue_process(), though I haven’t tested it and might be missing something. :-) Cheers, Nik-- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 8/19/15 5:47 AM, Nikolay Aleksandrov wrote: > >> On Aug 18, 2015, at 6:54 PM, David Ahern <dsa@cumulusnetworks.com> wrote: >> >> Directs route lookups to VRF table. Compiles out if NET_VRF is not >> enabled. With this patch able to successfully bring up ipsec tunnels >> in VRFs, even with duplicate network configuration (IPv4 tested). >> >> Signed-off-by: David Ahern <dsa@cumulusnetworks.com> >> --- >> net/ipv4/xfrm4_policy.c | 7 +++++-- >> net/ipv6/xfrm6_policy.c | 7 +++++-- >> 2 files changed, 10 insertions(+), 4 deletions(-) > > I think you should use the new vrf_master_index() helper that acquires rcu because > it looks possible to call ->decode_session() without rcu read lock, e.g. in the hold_timer > function xfrm_policy_queue_process(), though I haven’t tested it and might be missing > something. :-) I was digging into code paths yesterday. Today I added WARN_ON and seems like the rcu_read_lock is held: if (skb_dst(skb)) { WARN_ON(!rcu_read_lock_held() && !rcu_read_lock_bh_held()); oif = vrf_master_ifindex_rcu(skb_dst(skb)->dev) ? : skb_dst(skb)->dev->ifindex; pr_info("_decode_session: oif %d skb_dst(skb)->dev->ifindex %d\n", oif, skb_dst(skb)->dev->ifindex); } I get the printk, but not the WARN_ON splat. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Wed, Aug 19, 2015 at 11:35:55AM -0700, David Ahern wrote: > > > >I think you should use the new vrf_master_index() helper that acquires rcu because > >it looks possible to call ->decode_session() without rcu read lock, e.g. in the hold_timer > >function xfrm_policy_queue_process(), though I haven’t tested it and might be missing > >something. :-) > > I was digging into code paths yesterday. Today I added WARN_ON and > seems like the rcu_read_lock is held: > > if (skb_dst(skb)) { > WARN_ON(!rcu_read_lock_held() && !rcu_read_lock_bh_held()); > oif = vrf_master_ifindex_rcu(skb_dst(skb)->dev) ? > : skb_dst(skb)->dev->ifindex; > pr_info("_decode_session: oif %d skb_dst(skb)->dev->ifindex %d\n", > oif, skb_dst(skb)->dev->ifindex); > } > > I get the printk, but not the WARN_ON splat. Well, this depends on the codepath that called xfrm_decode_session(). It really think it was not called through xfrm_policy_queue_process() because this codepath is just used if the sysctl xfrm_larval_drop is switched off (on by default) and the required xfrm_state is not yet established. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/net/ipv4/xfrm4_policy.c b/net/ipv4/xfrm4_policy.c index 55b3c0f4dde5..35757f6af2d5 100644 --- a/net/ipv4/xfrm4_policy.c +++ b/net/ipv4/xfrm4_policy.c @@ -15,6 +15,7 @@ #include <net/dst.h> #include <net/xfrm.h> #include <net/ip.h> +#include <net/vrf.h> static struct xfrm_policy_afinfo xfrm4_policy_afinfo; @@ -107,8 +108,10 @@ _decode_session4(struct sk_buff *skb, struct flowi *fl, int reverse) struct flowi4 *fl4 = &fl->u.ip4; int oif = 0; - if (skb_dst(skb)) - oif = skb_dst(skb)->dev->ifindex; + if (skb_dst(skb)) { + oif = vrf_master_ifindex_rcu(skb_dst(skb)->dev) ? + : skb_dst(skb)->dev->ifindex; + } memset(fl4, 0, sizeof(struct flowi4)); fl4->flowi4_mark = skb->mark; diff --git a/net/ipv6/xfrm6_policy.c b/net/ipv6/xfrm6_policy.c index a74013d3eceb..4a88b89becf5 100644 --- a/net/ipv6/xfrm6_policy.c +++ b/net/ipv6/xfrm6_policy.c @@ -20,6 +20,7 @@ #include <net/ip.h> #include <net/ipv6.h> #include <net/ip6_route.h> +#include <net/vrf.h> #if IS_ENABLED(CONFIG_IPV6_MIP6) #include <net/mip6.h> #endif @@ -131,8 +132,10 @@ _decode_session6(struct sk_buff *skb, struct flowi *fl, int reverse) nexthdr = nh[nhoff]; - if (skb_dst(skb)) - oif = skb_dst(skb)->dev->ifindex; + if (skb_dst(skb)) { + oif = vrf_master_ifindex_rcu(skb_dst(skb)->dev) ? + : skb_dst(skb)->dev->ifindex; + } memset(fl6, 0, sizeof(struct flowi6)); fl6->flowi6_mark = skb->mark;
Directs route lookups to VRF table. Compiles out if NET_VRF is not enabled. With this patch able to successfully bring up ipsec tunnels in VRFs, even with duplicate network configuration (IPv4 tested). Signed-off-by: David Ahern <dsa@cumulusnetworks.com> --- net/ipv4/xfrm4_policy.c | 7 +++++-- net/ipv6/xfrm6_policy.c | 7 +++++-- 2 files changed, 10 insertions(+), 4 deletions(-)