user/sven/linux.git/include/net/ip6_fib.h, branch v3.12.41

ipv6: reset dst.expires value when clearing expire flag

2013-11-20T20:37:36Z

[ Upstream commit 01ba16d6ec85a1ec4669c75513a76b61ec53ee50 ] On receiving a packet too big icmp error we update the expire value by calling rt6_update_expires. This function uses dst_set_expires which is implemented that it can only reduce the expiration value of the dst entry. If we insert new routing non-expiry information into the ipv6 fib where we already have a matching rt6_info we only clear the RTF_EXPIRES flag in rt6i_flags and leave the dst.expires value as is. When new mtu information arrives for that cached dst_entry we again call dst_set_expires. This time it won't update the dst.expire value because we left the dst.expire value intact from the last update. So dst_set_expires won't touch dst.expires. Fix this by resetting dst.expires when clearing the RTF_EXPIRE flag. dst_set_expires checks for a zero expiration and updates the dst.expires. In the past this (not updating dst.expires) was necessary because dst.expire was placed in a union with the dst_entry *from reference and rt6_clean_expires did assign NULL to it. This split happend in ecd9883724b78cc72ed92c98bcb1a46c764fff21 ("ipv6: fix race condition regarding dst->expires and dst->from"). Reported-by: Steinar H. Gunderson Reported-by: Valentijn Sessink Cc: YOSHIFUJI Hideaki Acked-by: Eric Dumazet Tested-by: Valentijn Sessink Signed-off-by: Hannes Frederic Sowa Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

ipv6: prevent fib6_run_gc() contention

2013-08-01T21:16:20Z

On a high-traffic router with many processors and many IPv6 dst entries, soft lockup in fib6_run_gc() can occur when number of entries reaches gc_thresh. This happens because fib6_run_gc() uses fib6_gc_lock to allow only one thread to run the garbage collector but ip6_dst_gc() doesn't update net->ipv6.ip6_rt_last_gc until fib6_run_gc() returns. On a system with many entries, this can take some time so that in the meantime, other threads pass the tests in ip6_dst_gc() (ip6_rt_last_gc is still not updated) and wait for the lock. They then have to run the garbage collector one after another which blocks them for quite long. Resolve this by replacing special value ~0UL of expire parameter to fib6_run_gc() by explicit "force" parameter to choose between spin_lock_bh() and spin_trylock_bh() and call fib6_run_gc() with force=false if gc_thresh is reached but not max_size. Signed-off-by: Michal Kubecek Signed-off-by: David S. Miller

ipv6: fix race condition regarding dst->expires and dst->from.

2013-02-20T20:11:45Z

Eric Dumazet wrote: | Some strange crashes happen in rt6_check_expired(), with access | to random addresses. | | At first glance, it looks like the RTF_EXPIRES and | stuff added in commit 1716a96101c49186b | (ipv6: fix problem with expired dst cache) | are racy : same dst could be manipulated at the same time | on different cpus. | | At some point, our stack believes rt->dst.from contains a dst pointer, | while its really a jiffie value (as rt->dst.expires shares the same area | of memory) | | rt6_update_expires() should be fixed, or am I missing something ? | | CC Neil because of https://bugzilla.redhat.com/show_bug.cgi?id=892060 Because we do not have any locks for dst_entry, we cannot change essential structure in the entry; e.g., we cannot change reference to other entity. To fix this issue, split 'from' and 'expires' field in dst_entry out of union. Once it is 'from' is assigned in the constructor, keep the reference until the very last stage of the life time of the object. Of course, it is unsafe to change 'from', so make rt6_set_from simple just for fresh entries. Reported-by: Eric Dumazet Reported-by: Neil Horman CC: Gao Feng Signed-off-by: YOSHIFUJI Hideaki Reviewed-by: Eric Dumazet Reported-by: Steinar H. Gunderson Reviewed-by: Neil Horman Signed-off-by: David S. Miller

ipv6: Complete neighbour entry removal from dst_entry.

2013-01-17T23:38:19Z

CC: Cong Wang Signed-off-by: YOSHIFUJI Hideaki Signed-off-by: David S. Miller

ipv6: remove rt6i_peer_genid from rt6_info and its handler

2012-11-09T02:16:08Z

6431cbc25f(Create a mechanism for upward inetpeer propagation into routes) introduces these codes, but this mechanism is never enabled since rt6i_peer_genid always is zero whether it is not assigned or assigned by rt6_peer_genid(). After 5943634fc5 (ipv4: Maintain redirect and PMTU info in struct rtable again), the ipv4 related codes of this mechanism has been removed, I think we maybe able to remove them now. Signed-off-by: Li RongQing Signed-off-by: David S. Miller

ipv6: introduce ip6_rt_put()

2012-11-03T18:59:05Z

As suggested by Eric, we could introduce a helper function for ipv6 too, to avoid checking if rt is NULL before dst_release(). Cc: Eric Dumazet Cc: David S. Miller Signed-off-by: Cong Wang Signed-off-by: David S. Miller

ipv6: add support of equal cost multipath (ECMP)

2012-10-23T06:38:32Z

Each nexthop is added like a single route in the routing table. All routes that have the same metric/weight and destination but not the same gateway are considering as ECMP routes. They are linked together, through a list called rt6i_siblings. ECMP routes can be added in one shot, with RTA_MULTIPATH attribute or one after the other (in both case, the flag NLM_F_EXCL should not be set). The patch is based on a previous work from Luc Saillard . Signed-off-by: Nicolas Dichtel Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

2012-09-28T18:40:49Z

Conflicts: drivers/net/team/team.c drivers/net/usb/qmi_wwan.c net/batman-adv/bat_iv_ogm.c net/ipv4/fib_frontend.c net/ipv4/route.c net/l2tp/l2tp_netlink.c The team, fib_frontend, route, and l2tp_netlink conflicts were simply overlapping changes. qmi_wwan and bat_iv_ogm were of the "use HEAD" variety. With help from Antonio Quartulli. Signed-off-by: David S. Miller

ipv6: use net->rt_genid to check dst validity

2012-09-18T19:57:03Z

IPv6 dst should take care of rt_genid too. When a xfrm policy is inserted or deleted, all dst should be invalidated. To force the validation, dst entries should be created with ->obsolete set to DST_OBSOLETE_FORCE_CHK. This was already the case for all functions calling ip6_dst_alloc(), except for ip6_rt_copy(). As a consequence, we can remove the specific code in inet6_connection_sock. Signed-off-by: Nicolas Dichtel Signed-off-by: David S. Miller

ipv6: fix handling of blackhole and prohibit routes

2012-09-05T21:49:28Z

When adding a blackhole or a prohibit route, they were handling like classic routes. Moreover, it was only possible to add this kind of routes by specifying an interface. Bug already reported here: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=498498 Before the patch: $ ip route add blackhole 2001::1/128 RTNETLINK answers: No such device $ ip route add blackhole 2001::1/128 dev eth0 $ ip -6 route | grep 2001 2001::1 dev eth0 metric 1024 After: $ ip route add blackhole 2001::1/128 $ ip -6 route | grep 2001 blackhole 2001::1 dev lo metric 1024 error -22 v2: wrong patch v3: add a field fc_type in struct fib6_config to store RTN_* type Signed-off-by: Nicolas Dichtel Signed-off-by: David S. Miller