summaryrefslogtreecommitdiff
path: root/net/ipv4/fib_semantics.c
AgeCommit message (Collapse)Author
2015-07-24ipv4: consider TOS in fib_select_defaultJulian Anastasov
fib_select_default considers alternative routes only when res->fi is for the first alias in res->fa_head. In the common case this can happen only when the initial lookup matches the first alias with highest TOS value. This prevents the alternative routes to require specific TOS. This patch solves the problem as follows: - routes that require specific TOS should be returned by fib_select_default only when TOS matches, as already done in fib_table_lookup. This rule implies that depending on the TOS we can have many different lists of alternative gateways and we have to keep the last used gateway (fa_default) in first alias for the TOS instead of using single tb_default value. - as the aliases are ordered by many keys (TOS desc, fib_priority asc), we restrict the possible results to routes with matching TOS and lowest metric (fib_priority) and routes that match any TOS, again with lowest metric. For example, packet with TOS 8 can not use gw3 (not lowest metric), gw4 (different TOS) and gw6 (not lowest metric), all other gateways can be used: tos 8 via gw1 metric 2 <--- res->fa_head and res->fi tos 8 via gw2 metric 2 tos 8 via gw3 metric 3 tos 4 via gw4 tos 0 via gw5 tos 0 via gw6 metric 1 Reported-by: Hagen Paul Pfeifer <hagen@jauu.net> Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-24ipv4: fib_select_default should match the prefixJulian Anastasov
fib_trie starting from 4.1 can link fib aliases from different prefixes in same list. Make sure the alternative gateways are in same table and for same prefix (0) by checking tb_id and fa_slen. Fixes: 79e5ad2ceb00 ("fib_trie: Remove leaf_info") Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-28ipv4: fix RCU lockdep warning from linkdown changesAndy Gospodarek
The following lockdep splat was seen due to the wrong context for grabbing in_dev. =============================== [ INFO: suspicious RCU usage. ] 4.1.0-next-20150626-dbg-00020-g54a6d91-dirty #244 Not tainted ------------------------------- include/linux/inetdevice.h:205 suspicious rcu_dereference_check() usage! other info that might help us debug this: rcu_scheduler_active = 1, debug_locks = 0 2 locks held by ip/403: #0: (rtnl_mutex){+.+.+.}, at: [<ffffffff81453305>] rtnl_lock+0x17/0x19 #1: ((inetaddr_chain).rwsem){.+.+.+}, at: [<ffffffff8105c327>] __blocking_notifier_call_chain+0x35/0x6a stack backtrace: CPU: 2 PID: 403 Comm: ip Not tainted 4.1.0-next-20150626-dbg-00020-g54a6d91-dirty #244 0000000000000001 ffff8800b189b728 ffffffff8150a542 ffffffff8107a8b3 ffff880037bbea40 ffff8800b189b758 ffffffff8107cb74 ffff8800379dbd00 ffff8800bec85800 ffff8800bf9e13c0 00000000000000ff ffff8800b189b7d8 Call Trace: [<ffffffff8150a542>] dump_stack+0x4c/0x6e [<ffffffff8107a8b3>] ? up+0x39/0x3e [<ffffffff8107cb74>] lockdep_rcu_suspicious+0xf7/0x100 [<ffffffff814b63c3>] fib_dump_info+0x227/0x3e2 [<ffffffff814b6624>] rtmsg_fib+0xa6/0x116 [<ffffffff814b978f>] fib_table_insert+0x316/0x355 [<ffffffff814b362e>] fib_magic+0xb7/0xc7 [<ffffffff814b4803>] fib_add_ifaddr+0xb1/0x13b [<ffffffff814b4d09>] fib_inetaddr_event+0x36/0x90 [<ffffffff8105c086>] notifier_call_chain+0x4c/0x71 [<ffffffff8105c340>] __blocking_notifier_call_chain+0x4e/0x6a [<ffffffff8105c370>] blocking_notifier_call_chain+0x14/0x16 [<ffffffff814a7f50>] __inet_insert_ifa+0x1a5/0x1b3 [<ffffffff814a894d>] inet_rtm_newaddr+0x350/0x35f [<ffffffff81457866>] rtnetlink_rcv_msg+0x17b/0x18a [<ffffffff8107e7c3>] ? trace_hardirqs_on+0xd/0xf [<ffffffff8146965f>] ? netlink_deliver_tap+0x1cb/0x1f7 [<ffffffff814576eb>] ? rtnl_newlink+0x72a/0x72a ... This patch resolves that splat. Signed-off-by: Andy Gospodarek <gospo@cumulusnetworks.com> Reported-by: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-24net: ipv4 sysctl option to ignore routes when nexthop link is downAndy Gospodarek
This feature is only enabled with the new per-interface or ipv4 global sysctls called 'ignore_routes_with_linkdown'. net.ipv4.conf.all.ignore_routes_with_linkdown = 0 net.ipv4.conf.default.ignore_routes_with_linkdown = 0 net.ipv4.conf.lo.ignore_routes_with_linkdown = 0 ... When the above sysctls are set, will report to userspace that a route is dead and will no longer resolve to this nexthop when performing a fib lookup. This will signal to userspace that the route will not be selected. The signalling of a RTNH_F_DEAD is only passed to userspace if the sysctl is enabled and link is down. This was done as without it the netlink listeners would have no idea whether or not a nexthop would be selected. The kernel only sets RTNH_F_DEAD internally if the interface has IFF_UP cleared. With the new sysctl set, the following behavior can be observed (interface p8p1 is link-down): default via 10.0.5.2 dev p9p1 10.0.5.0/24 dev p9p1 proto kernel scope link src 10.0.5.15 70.0.0.0/24 dev p7p1 proto kernel scope link src 70.0.0.1 80.0.0.0/24 dev p8p1 proto kernel scope link src 80.0.0.1 dead linkdown 90.0.0.0/24 via 80.0.0.2 dev p8p1 metric 1 dead linkdown 90.0.0.0/24 via 70.0.0.2 dev p7p1 metric 2 90.0.0.1 via 70.0.0.2 dev p7p1 src 70.0.0.1 cache local 80.0.0.1 dev lo src 80.0.0.1 cache <local> 80.0.0.2 via 10.0.5.2 dev p9p1 src 10.0.5.15 cache While the route does remain in the table (so it can be modified if needed rather than being wiped away as it would be if IFF_UP was cleared), the proper next-hop is chosen automatically when the link is down. Now interface p8p1 is linked-up: default via 10.0.5.2 dev p9p1 10.0.5.0/24 dev p9p1 proto kernel scope link src 10.0.5.15 70.0.0.0/24 dev p7p1 proto kernel scope link src 70.0.0.1 80.0.0.0/24 dev p8p1 proto kernel scope link src 80.0.0.1 90.0.0.0/24 via 80.0.0.2 dev p8p1 metric 1 90.0.0.0/24 via 70.0.0.2 dev p7p1 metric 2 192.168.56.0/24 dev p2p1 proto kernel scope link src 192.168.56.2 90.0.0.1 via 80.0.0.2 dev p8p1 src 80.0.0.1 cache local 80.0.0.1 dev lo src 80.0.0.1 cache <local> 80.0.0.2 dev p8p1 src 80.0.0.1 cache and the output changes to what one would expect. If the sysctl is not set, the following output would be expected when p8p1 is down: default via 10.0.5.2 dev p9p1 10.0.5.0/24 dev p9p1 proto kernel scope link src 10.0.5.15 70.0.0.0/24 dev p7p1 proto kernel scope link src 70.0.0.1 80.0.0.0/24 dev p8p1 proto kernel scope link src 80.0.0.1 linkdown 90.0.0.0/24 via 80.0.0.2 dev p8p1 metric 1 linkdown 90.0.0.0/24 via 70.0.0.2 dev p7p1 metric 2 Since the dead flag does not appear, there should be no expectation that the kernel would skip using this route due to link being down. v2: Split kernel changes into 2 patches, this actually makes a behavioral change if the sysctl is set. Also took suggestion from Alex to simplify code by only checking sysctl during fib lookup and suggestion from Scott to add a per-interface sysctl. v3: Code clean-ups to make it more readable and efficient as well as a reverse path check fix. v4: Drop binary sysctl v5: Whitespace fixups from Dave v6: Style changes from Dave and checkpatch suggestions v7: One more checkpatch fixup Signed-off-by: Andy Gospodarek <gospo@cumulusnetworks.com> Signed-off-by: Dinesh Dutt <ddutt@cumulusnetworks.com> Acked-by: Scott Feldman <sfeldma@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-24net: track link-status of ipv4 nexthopsAndy Gospodarek
Add a fib flag called RTNH_F_LINKDOWN to any ipv4 nexthops that are reachable via an interface where carrier is off. No action is taken, but additional flags are passed to userspace to indicate carrier status. This also includes a cleanup to fib_disable_ip to more clearly indicate what event made the function call to replace the more cryptic force option previously used. v2: Split out kernel functionality into 2 patches, this patch simply sets and clears new nexthop flag RTNH_F_LINKDOWN. v3: Cleanups suggested by Alex as well as a bug noticed in fib_sync_down_dev and fib_sync_up when multipath was not enabled. v5: Whitespace and variable declaration fixups suggested by Dave. v6: Style fixups noticed by Dave; ran checkpatch to be sure I got them all. Signed-off-by: Andy Gospodarek <gospo@cumulusnetworks.com> Signed-off-by: Dinesh Dutt <ddutt@cumulusnetworks.com> Acked-by: Scott Feldman <sfeldma@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-02ipv4: remove the unnecessary codes in fib_info_hash_moveLi RongQing
The whole hlist will be moved, so not need to call hlist_del before add the hlist_node to other hlist_head. Signed-off-by: Li RongQing <roy.qing.li@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-03ipv4: coding style: comparison for equality with NULLIan Morris
The ipv4 code uses a mixture of coding styles. In some instances check for NULL pointer is done as x == NULL and sometimes as !x. !x is preferred according to checkpatch and this patch makes the code consistent by adopting the latter form. No changes detected by objdiff. Signed-off-by: Ian Morris <ipm@chirality.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-31netlink: implement nla_get_in_addr and nla_get_in6_addrJiri Benc
Those are counterparts to nla_put_in_addr and nla_put_in6_addr. Signed-off-by: Jiri Benc <jbenc@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-31netlink: implement nla_put_in_addr and nla_put_in6_addrJiri Benc
IP addresses are often stored in netlink attributes. Add generic functions to do that. For nla_put_in_addr, it would be nicer to pass struct in_addr but this is not used universally throughout the kernel, in way too many places __be32 is used to store IPv4 address. Signed-off-by: Jiri Benc <jbenc@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-12net: Kill hold_net release_netEric W. Biederman
hold_net and release_net were an idea that turned out to be useless. The code has been disabled since 2008. Kill the code it is long past due. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-02-27fib_trie: Convert fib_alias to hlist from listAlexander Duyck
There isn't any advantage to having it as a list and by making it an hlist we make the fib_alias more compatible with the list_info in terms of the type of list used. Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-25fib_trie: Move fib_find_alias to file where it is usedAlexander Duyck
The function fib_find_alias is only accessed by functions in fib_trie.c as such it makes sense to relocate it and cast it as static so that the compiler can take advantage of optimizations it can do to it as a local function. Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-18netlink: make nlmsg_end() and genlmsg_end() voidJohannes Berg
Contrary to common expectations for an "int" return, these functions return only a positive value -- if used correctly they cannot even return 0 because the message header will necessarily be in the skb. This makes the very common pattern of if (genlmsg_end(...) < 0) { ... } be a whole bunch of dead code. Many places also simply do return nlmsg_end(...); and the caller is expected to deal with it. This also commonly (at least for me) causes errors, because it is very common to write if (my_function(...)) /* error condition */ and if my_function() does "return nlmsg_end()" this is of course wrong. Additionally, there's not a single place in the kernel that actually needs the message length returned, and if anyone needs it later then it'll be very easy to just use skb->len there. Remove this, and make the functions void. This removes a bunch of dead code as described above. The patch adds lines because I did - return nlmsg_end(...); + nlmsg_end(...); + return 0; I could have preserved all the function's return values by returning skb->len, but instead I've audited all the places calling the affected functions and found that none cared. A few places actually compared the return value with <= 0 in dump functionality, but that could just be changed to < 0 with no change in behaviour, so I opted for the more efficient version. One instance of the error I've made numerous times now is also present in net/phonet/pn_netlink.c in the route_dumpit() function - it didn't check for <0 or <=0 and thus broke out of the loop every single time. I've preserved this since it will (I think) have caused the messages to userspace to be formatted differently with just a single message for every SKB returned to userspace. It's possible that this isn't needed for the tools that actually use this, but I don't even know what they are so couldn't test that changing this behaviour would be acceptable. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-05net: tcp: add RTAX_CC_ALGO fib handlingDaniel Borkmann
This patch adds the minimum necessary for the RTAX_CC_ALGO congestion control metric to be set up and dumped back to user space. While the internal representation of RTAX_CC_ALGO is handled as a u32 key, we avoided to expose this implementation detail to user space, thus instead, we chose the netlink attribute that is being exchanged between user space to be the actual congestion control algorithm name, similarly as in the setsockopt(2) API in order to allow for maximum flexibility, even for 3rd party modules. It is a bit unfortunate that RTAX_QUICKACK used up a whole RTAX slot as it should have been stored in RTAX_FEATURES instead, we first thought about reusing it for the congestion control key, but it brings more complications and/or confusion than worth it. Joint work with Florian Westphal. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-14ipv4: fix nexthop attlen check in fib_nh_matchJiri Pirko
fib_nh_match does not match nexthops correctly. Example: ip route add 172.16.10/24 nexthop via 192.168.122.12 dev eth0 \ nexthop via 192.168.122.13 dev eth0 ip route del 172.16.10/24 nexthop via 192.168.122.14 dev eth0 \ nexthop via 192.168.122.15 dev eth0 Del command is successful and route is removed. After this patch applied, the route is correctly matched and result is: RTNETLINK answers: No such process Please consider this for stable trees as well. Fixes: 4e902c57417c4 ("[IPv4]: FIB configuration using struct fib_config") Signed-off-by: Jiri Pirko <jiri@resnulli.us> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-05ipv4: fix a race in update_or_create_fnhe()Eric Dumazet
nh_exceptions is effectively used under rcu, but lacks proper barriers. Between kzalloc() and setting of nh->nh_exceptions(), we need a proper memory barrier. Signed-off-by: Eric Dumazet <edumazet@google.com> Fixes: 4895c771c7f00 ("ipv4: Add FIB nexthop exceptions.") Signed-off-by: David S. Miller <davem@davemloft.net>
2014-05-07ipv4: fib_semantics: increment fib_info_cnt after fib_info allocationSergey Popovich
Increment fib_info_cnt in fib_create_info() right after successfuly alllocating fib_info structure, overwise fib_metrics allocation failure leads to fib_info_cnt incorrectly decremented in free_fib_info(), called on error path from fib_create_info(). Signed-off-by: Sergey Popovich <popovich_sergei@mail.ru> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-04-16ipv4, fib: pass LOOPBACK_IFINDEX instead of 0 to flowi4_iifCong Wang
As suggested by Julian: Simply, flowi4_iif must not contain 0, it does not look logical to ignore all ip rules with specified iif. because in fib_rule_match() we do: if (rule->iifindex && (rule->iifindex != fl->flowi_iif)) goto out; flowi4_iif should be LOOPBACK_IFINDEX by default. We need to move LOOPBACK_IFINDEX to include/net/flow.h: 1) It is mostly used by flowi_iif 2) Fix the following compile error if we use it in flow.h by the patches latter: In file included from include/linux/netfilter.h:277:0, from include/net/netns/netfilter.h:5, from include/net/net_namespace.h:21, from include/linux/netdevice.h:43, from include/linux/icmpv6.h:12, from include/linux/ipv6.h:61, from include/net/ipv6.h:16, from include/linux/sunrpc/clnt.h:27, from include/linux/nfs_fs.h:30, from init/do_mounts.c:32: include/net/flow.h: In function ‘flowi4_init_output’: include/net/flow.h:84:32: error: ‘LOOPBACK_IFINDEX’ undeclared (first use in this function) Cc: Eric Biederman <ebiederm@xmission.com> Cc: Julian Anastasov <ja@ssi.bg> Cc: David S. Miller <davem@davemloft.net> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: Cong Wang <cwang@twopensource.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-28ipv4: make fib_detect_death staticStephen Hemminger
Make fib_detect_death function static only used in one file. Signed-off-by: Stephen Hemminger <stephen@networkplumber.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-18fib: Use const struct nl_info * in rtmsg_fibJoe Perches
The rtmsg_fib function doesn't modify this argument so mark it const. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-28ipv4: use next hop exceptions also for input routesTimo Teräs
Commit d2d68ba9 (ipv4: Cache input routes in fib_info nexthops) assmued that "locally destined, and routed packets, never trigger PMTU events or redirects that will be processed by us". However, it seems that tunnel devices do trigger PMTU events in certain cases. At least ip_gre, ip6_gre, sit, and ipip do use the inner flow's skb_dst(skb)->ops->update_pmtu to propage mtu information from the outer flows. These can cause the inner flow mtu to be decreased. If next hop exceptions are not consulted for pmtu, IP fragmentation will not be done properly for these routes. It also seems that we really need to have the PMTU information always for netfilter TCPMSS clamp-to-pmtu feature to work properly. So for the time being, cache separate copies of input routes for each next hop exception. Signed-off-by: Timo Teräs <timo.teras@iki.fi> Reviewed-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-02-27hlist: drop the node parameter from iteratorsSasha Levin
I'm not sure why, but the hlist for each entry iterators were conceived list_for_each_entry(pos, head, member) The hlist ones were greedy and wanted an extra parameter: hlist_for_each_entry(tpos, pos, head, member) Why did they need an extra pos parameter? I'm not quite sure. Not only they don't really need it, it also prevents the iterator from looking exactly like the list iterator, which is unfortunate. Besides the semantic patch, there was some manual work required: - Fix up the actual hlist iterators in linux/list.h - Fix up the declaration of other iterators based on the hlist ones. - A very small amount of places were using the 'node' parameter, this was modified to use 'obj->member' instead. - Coccinelle didn't handle the hlist_for_each_entry_safe iterator properly, so those had to be fixed up manually. The semantic patch which is mostly the work of Peter Senna Tschudin is here: @@ iterator name hlist_for_each_entry, hlist_for_each_entry_continue, hlist_for_each_entry_from, hlist_for_each_entry_rcu, hlist_for_each_entry_rcu_bh, hlist_for_each_entry_continue_rcu_bh, for_each_busy_worker, ax25_uid_for_each, ax25_for_each, inet_bind_bucket_for_each, sctp_for_each_hentry, sk_for_each, sk_for_each_rcu, sk_for_each_from, sk_for_each_safe, sk_for_each_bound, hlist_for_each_entry_safe, hlist_for_each_entry_continue_rcu, nr_neigh_for_each, nr_neigh_for_each_safe, nr_node_for_each, nr_node_for_each_safe, for_each_gfn_indirect_valid_sp, for_each_gfn_sp, for_each_host; type T; expression a,c,d,e; identifier b; statement S; @@ -T b; <+... when != b ( hlist_for_each_entry(a, - b, c, d) S | hlist_for_each_entry_continue(a, - b, c) S | hlist_for_each_entry_from(a, - b, c) S | hlist_for_each_entry_rcu(a, - b, c, d) S | hlist_for_each_entry_rcu_bh(a, - b, c, d) S | hlist_for_each_entry_continue_rcu_bh(a, - b, c) S | for_each_busy_worker(a, c, - b, d) S | ax25_uid_for_each(a, - b, c) S | ax25_for_each(a, - b, c) S | inet_bind_bucket_for_each(a, - b, c) S | sctp_for_each_hentry(a, - b, c) S | sk_for_each(a, - b, c) S | sk_for_each_rcu(a, - b, c) S | sk_for_each_from -(a, b) +(a) S + sk_for_each_from(a) S | sk_for_each_safe(a, - b, c, d) S | sk_for_each_bound(a, - b, c) S | hlist_for_each_entry_safe(a, - b, c, d, e) S | hlist_for_each_entry_continue_rcu(a, - b, c) S | nr_neigh_for_each(a, - b, c) S | nr_neigh_for_each_safe(a, - b, c, d) S | nr_node_for_each(a, - b, c) S | nr_node_for_each_safe(a, - b, c, d) S | - for_each_gfn_sp(a, c, d, b) S + for_each_gfn_sp(a, c, d) S | - for_each_gfn_indirect_valid_sp(a, c, d, b) S + for_each_gfn_indirect_valid_sp(a, c, d) S | for_each_host(a, - b, c) S | for_each_host_safe(a, - b, c, d) S | for_each_mesh_entry(a, - b, c, d) S ) ...+> [akpm@linux-foundation.org: drop bogus change from net/ipv4/raw.c] [akpm@linux-foundation.org: drop bogus hunk from net/ipv6/raw.c] [akpm@linux-foundation.org: checkpatch fixes] [akpm@linux-foundation.org: fix warnings] [akpm@linux-foudnation.org: redo intrusive kvm changes] Tested-by: Peter Senna Tschudin <peter.senna@gmail.com> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Sasha Levin <sasha.levin@oracle.com> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Gleb Natapov <gleb@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-22ipv4: 16 slots in initial fib_info hash tableEric Dumazet
A small host typically needs ~10 fib_info structures, so create initial hash table with 16 slots instead of only one. This removes potential false sharing and reallocs/rehashes (1->2->4->8->16) Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-10-08ipv4: make sure nh_pcpu_rth_output is always allocatedJulian Anastasov
Avoid checking nh_pcpu_rth_output in fast path, abort fib_info creation on alloc_percpu failure. Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-10-04ipv4: add a fib_type to fib_infoEric Dumazet
commit d2d68ba9fe8 (ipv4: Cache input routes in fib_info nexthops.) introduced a regression for forwarding. This was hard to reproduce but the symptom was that packets were delivered to local host instead of being forwarded. David suggested to add fib_type to fib_info so that we dont inadvertently share same fib_info for different purposes. With help from Julian Anastasov who provided very helpful hints, reproduced here : <quote> Can it be a problem related to fib_info reuse from different routes. For example, when local IP address is created for subnet we have: broadcast 192.168.0.255 dev DEV proto kernel scope link src 192.168.0.1 192.168.0.0/24 dev DEV proto kernel scope link src 192.168.0.1 local 192.168.0.1 dev DEV proto kernel scope host src 192.168.0.1 The "dev DEV proto kernel scope link src 192.168.0.1" is a reused fib_info structure where we put cached routes. The result can be same fib_info for 192.168.0.255 and 192.168.0.0/24. RTN_BROADCAST is cached only for input routes. Incoming broadcast to 192.168.0.255 can be cached and can cause problems for traffic forwarded to 192.168.0.0/24. So, this patch should solve the problem because it separates the broadcast from unicast traffic. And the ip_route_input_slow caching will work for local and broadcast input routes (above routes 1 and 3) just because they differ in scope and use different fib_info. </quote> Many thanks to Chris Clayton for his patience and help. Reported-by: Chris Clayton <chris2553@googlemail.com> Bisected-by: Chris Clayton <chris2553@googlemail.com> Reported-by: Dave Jones <davej@redhat.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Julian Anastasov <ja@ssi.bg> Tested-by: Chris Clayton <chris2553@googlemail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-09-10netlink: Rename pid to portid to avoid confusionEric W. Biederman
It is a frequent mistake to confuse the netlink port identifier with a process identifier. Try to reduce this confusion by renaming fields that hold port identifiers portid instead of pid. I have carefully avoided changing the structures exported to userspace to avoid changing the userspace API. I have successfully built an allyesconfig kernel with this change. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Acked-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-31ipv4: Cache routes in nexthop exception entries.David S. Miller
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-31ipv4: percpu nh_rth_output cacheEric Dumazet
Input path is mostly run under RCU and doesnt touch dst refcnt But output path on forwarding or UDP workloads hits badly dst refcount, and we have lot of false sharing, for example in ipv4_mtu() when reading rt->rt_pmtu Using a percpu cache for nh_rth_output gives a nice performance increase at a small cost. 24 udpflood test on my 24 cpu machine (dummy0 output device) (each process sends 1.000.000 udp frames, 24 processes are started) before : 5.24 s after : 2.06 s For reference, time on linux-3.5 : 6.60 s Signed-off-by: Eric Dumazet <edumazet@google.com> Tested-by: Alexander Duyck <alexander.h.duyck@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-31ipv4: Restore old dst_free() behavior.Eric Dumazet
commit 404e0a8b6a55 (net: ipv4: fix RCU races on dst refcounts) tried to solve a race but added a problem at device/fib dismantle time : We really want to call dst_free() as soon as possible, even if sockets still have dst in their cache. dst_release() calls in free_fib_info_rcu() are not welcomed. Root of the problem was that now we also cache output routes (in nh_rth_output), we must use call_rcu() instead of call_rcu_bh() in rt_free(), because output route lookups are done in process context. Based on feedback and initial patch from David Miller (adding another call_rcu_bh() call in fib, but it appears it was not the right fix) I left the inet_sk_rx_dst_set() helper and added __rcu attributes to nh_rth_output and nh_rth_input to better document what is going on in this code. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-30net: ipv4: fix RCU races on dst refcountsEric Dumazet
commit c6cffba4ffa2 (ipv4: Fix input route performance regression.) added various fatal races with dst refcounts. crashes happen on tcp workloads if routes are added/deleted at the same time. The dst_free() calls from free_fib_info_rcu() are clearly racy. We need instead regular dst refcounting (dst_release()) and make sure dst_release() is aware of RCU grace periods : Add DST_RCU_FREE flag so that dst_release() respects an RCU grace period before dst destruction for cached dst Introduce a new inet_sk_rx_dst_set() helper, using atomic_inc_not_zero() to make sure we dont increase a zero refcount (On a dst currently waiting an rcu grace period before destruction) rt_cache_route() must take a reference on the new cached route, and release it if was not able to install it. With this patch, my machines survive various benchmarks. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-26ipv4: Fix input route performance regression.David S. Miller
With the routing cache removal we lost the "noref" code paths on input, and this can kill some routing workloads. Reinstate the noref path when we hit a cached route in the FIB nexthops. With help from Eric Dumazet. Reported-by: Alexander Duyck <alexander.duyck@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-20ipv4: Cache input routes in fib_info nexthops.David S. Miller
Caching input routes is slightly simpler than output routes, since we don't need to be concerned with nexthop exceptions. (locally destined, and routed packets, never trigger PMTU events or redirects that will be processed by us). However, we have to elide caching for the DIRECTSRC and non-zero itag cases. Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-20ipv4: Cache output routes in fib_info nexthops.David S. Miller
If we have an output route that lacks nexthop exceptions, we can cache it in the FIB info nexthop. Such routes will have DST_HOST cleared because such routes refer to a family of destinations, rather than just one. The sequence of the handling of exceptions during route lookup is adjusted to make the logic work properly. Before we allocate the route, we lookup the exception. Then we know if we will cache this route or not, and therefore whether DST_HOST should be set on the allocated route. Then we use DST_HOST to key off whether we should store the resulting route, during rt_set_nexthop(), in the FIB nexthop cache. With help from Eric Dumazet. Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-17ipv4: fix rcu splatEric Dumazet
free_nh_exceptions() should use rcu_dereference_protected(..., 1) since its called after one RCU grace period. Also add some const-ification in recent code. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-17ipv4: Add FIB nexthop exceptions.David S. Miller
In a regime where we have subnetted route entries, we need a way to store persistent storage about destination specific learned values such as redirects and PMTU values. This is implemented here via nexthop exceptions. The initial implementation is a 2048 entry hash table with relaiming starting at chain length 5. A more sophisticated scheme can be devised if that proves necessary. Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-10ipv4: Enforce max MTU metric at route insertion time.David S. Miller
Rather than at every struct rtable creation. Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-05ipv4: Avoid overhead when no custom FIB rules are installed.David S. Miller
If the user hasn't actually installed any custom rules, or fiddled with the default ones, don't go through the whole FIB rules layer. It's just pure overhead. Instead do what we do with CONFIG_IP_MULTIPLE_TABLES disabled, check the individual tables by hand, one by one. Also, move fib_num_tclassid_users into the ipv4 network namespace. Signed-off-by: David S. Miller <davem@davemloft.net>
2012-06-29ipv4: Elide fib_validate_source() completely when possible.David S. Miller
If rpfilter is off (or the SKB has an IPSEC path) and there are not tclassid users, we don't have to do anything at all when fib_validate_source() is invoked besides setting the itag to zero. We monitor tclassid uses with a counter (modified only under RTNL and marked __read_mostly) and we protect the fib_validate_source() real work with a test against this counter and whether rpfilter is to be done. Having a way to know whether we need no tclassid processing or not also opens the door for future optimized rpfilter algorithms that do not perform full FIB lookups. Signed-off-by: David S. Miller <davem@davemloft.net>
2012-06-17ipv4: Cap ADVMSS metric in the FIB rather than the routing cache.David S. Miller
It makes no sense to execute this limit test every time we create a routing cache entry. We can't simply error out on these things since we've silently accepted and truncated them forever. Signed-off-by: David S. Miller <davem@davemloft.net>
2012-05-24ipv4: fix the rcu race between free_fib_info and ip_route_output_slowYanmin Zhang
We hit a kernel OOPS. <3>[23898.789643] BUG: sleeping function called from invalid context at /data/buildbot/workdir/ics/hardware/intel/linux-2.6/arch/x86/mm/fault.c:1103 <3>[23898.862215] in_atomic(): 0, irqs_disabled(): 0, pid: 10526, name: Thread-6683 <4>[23898.967805] HSU serial 0000:00:05.1: 0000:00:05.2:HSU serial prevented me to suspend... <4>[23899.258526] Pid: 10526, comm: Thread-6683 Tainted: G W 3.0.8-137685-ge7742f9 #1 <4>[23899.357404] HSU serial 0000:00:05.1: 0000:00:05.2:HSU serial prevented me to suspend... <4>[23899.904225] Call Trace: <4>[23899.989209] [<c1227f50>] ? pgtable_bad+0x130/0x130 <4>[23900.000416] [<c1238c2a>] __might_sleep+0x10a/0x110 <4>[23900.007357] [<c1228021>] do_page_fault+0xd1/0x3c0 <4>[23900.013764] [<c18e9ba9>] ? restore_all+0xf/0xf <4>[23900.024024] [<c17c007b>] ? napi_complete+0x8b/0x690 <4>[23900.029297] [<c1227f50>] ? pgtable_bad+0x130/0x130 <4>[23900.123739] [<c1227f50>] ? pgtable_bad+0x130/0x130 <4>[23900.128955] [<c18ea0c3>] error_code+0x5f/0x64 <4>[23900.133466] [<c1227f50>] ? pgtable_bad+0x130/0x130 <4>[23900.138450] [<c17f6298>] ? __ip_route_output_key+0x698/0x7c0 <4>[23900.144312] [<c17f5f8d>] ? __ip_route_output_key+0x38d/0x7c0 <4>[23900.150730] [<c17f63df>] ip_route_output_flow+0x1f/0x60 <4>[23900.156261] [<c181de58>] ip4_datagram_connect+0x188/0x2b0 <4>[23900.161960] [<c18e981f>] ? _raw_spin_unlock_bh+0x1f/0x30 <4>[23900.167834] [<c18298d6>] inet_dgram_connect+0x36/0x80 <4>[23900.173224] [<c14f9e88>] ? _copy_from_user+0x48/0x140 <4>[23900.178817] [<c17ab9da>] sys_connect+0x9a/0xd0 <4>[23900.183538] [<c132e93c>] ? alloc_file+0xdc/0x240 <4>[23900.189111] [<c123925d>] ? sub_preempt_count+0x3d/0x50 Function free_fib_info resets nexthop_nh->nh_dev to NULL before releasing fi. Other cpu might be accessing fi. Fixing it by delaying the releasing. With the patch, we ran MTBF testing on Android mobile for 12 hours and didn't trigger the issue. Thank Eric for very detailed review/checking the issue. Signed-off-by: Yanmin Zhang <yanmin_zhang@linux.intel.com> Signed-off-by: Kun Jiang <kunx.jiang@intel.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-04-10Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
2012-04-02ipv4: Stop using NLA_PUT*().David S. Miller
These macros contain a hidden goto, and are thus extremely error prone and make code hard to audit. Signed-off-by: David S. Miller <davem@davemloft.net>
2012-03-28Remove all #inclusions of asm/system.hDavid Howells
Remove all #inclusions of asm/system.h preparatory to splitting and killing it. Performed with the following command: perl -p -i -e 's!^#\s*include\s*<asm/system[.]h>.*\n!!' `grep -Irl '^#\s*include\s*<asm/system[.]h>' *` Signed-off-by: David Howells <dhowells@redhat.com>
2012-03-11net: Convert printks to pr_<level>Joe Perches
Use a more current kernel messaging style. Convert a printk block to print_hex_dump. Coalesce formats, align arguments. Use %s, __func__ instead of embedding function names. Some messages that were prefixed with <foo>_close are now prefixed with <foo>_fini. Some ah4 and esp messages are now not prefixed with "ip ". The intent of this patch is to later add something like #define pr_fmt(fmt) "IPv4: " fmt. to standardize the output messages. Text size is trivially reduced. (x86-32 allyesconfig) $ size net/ipv4/built-in.o* text data bss dec hex filename 887888 31558 249696 1169142 11d6f6 net/ipv4/built-in.o.new 887934 31558 249800 1169292 11d78c net/ipv4/built-in.o.old Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-09-16ipv4: Fix fib_info->fib_metrics leakYan, Zheng
Commit 4670994d(net,rcu: convert call_rcu(fc_rport_free_rcu) to kfree_rcu()) introduced a memory leak. This patch reverts it. Signed-off-by: Zheng Yan <zheng.z.yan@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-05-07net,rcu: convert call_rcu(fc_rport_free_rcu) to kfree_rcu()Lai Jiangshan
The rcu callback fc_rport_free_rcu() just calls a kfree(), so we use kfree_rcu() instead of the call_rcu(fc_rport_free_rcu). Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2011-03-24ipv4: Fix nexthop caching wrt. scoping.David S. Miller
Move the scope value out of the fib alias entries and into fib_info, so that we always use the correct scope when recomputing the nexthop cached source address. Reported-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-24ipv4: Invalidate nexthop cache nh_saddr more correctly.David S. Miller
Any operation that: 1) Brings up an interface 2) Adds an IP address to an interface 3) Deletes an IP address from an interface can potentially invalidate the nh_saddr value, requiring it to be recomputed. Perform the recomputation lazily using a generation ID. Reported-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-24ipv4: fix fib metricsEric Dumazet
Alessandro Suardi reported that we could not change route metrics : ip ro change default .... advmss 1400 This regression came with commit 9c150e82ac50 (Allocate fib metrics dynamically). fib_metrics is no longer an array, but a pointer to an array. Reported-by: Alessandro Suardi <alessandro.suardi@gmail.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Tested-by: Alessandro Suardi <alessandro.suardi@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-12ipv4: Use flowi4 in FIB layer.David S. Miller
Signed-off-by: David S. Miller <davem@davemloft.net>