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2015-07-21route: Per route IP tunnel metadata via lightweight tunnelThomas Graf1-1/+1
This introduces a new IP tunnel lightweight tunnel type which allows to specify IP tunnel instructions per route. Only IPv4 is supported at this point. Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-21route: Extend flow representation with tunnel keyThomas Graf1-0/+8
Add a new flowi_tunnel structure which is a subset of ip_tunnel_key to allow routes to match on tunnel metadata. For now, the tunnel id is added to flowi_tunnel which allows for routes to be bound to specific virtual tunnels. Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-21dst: Metadata destinationsThomas Graf1-0/+2
Introduces a new dst_metadata which enables to carry per packet metadata between forwarding and processing elements via the skb->dst pointer. The structure is set up to be a union. Thus, each separate type of metadata requires its own dst instance. If demand arises to carry multiple types of metadata concurrently, metadata dst entries can be made stackable. The metadata dst entry is refcnt'ed as expected for now but a non reference counted use is possible if the reference is forced before queueing the skb. In order to allow allocating dsts with variable length, the existing dst_alloc() is split into a dst_alloc() and dst_init() function. The existing dst_init() function to initialize the subsystem is being renamed to dst_subsys_init() to make it clear what is what. The check before ip_route_input() is changed to ignore metadata dsts and drop the dst inside the routing function thus allowing to interpret metadata in a later commit. Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-21ipv4: redirect dst output to lwtunnel outputRoopa Prabhu1-0/+2
For input routes with tunnel encap state this patch redirects dst output functions to lwtunnel_output which later resolves to the corresponding lwtunnel output function. This has been tested to work with mpls ip tunnels. Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-21ipv4: support for fib route lwtunnel encap attributesRoopa Prabhu1-2/+14
This patch adds support in ipv4 fib functions to parse user provided encap attributes and attach encap state data to fib_nh and rtable. Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-10route: remove unsed variable in __mkroute_inputMasatake YAMATO1-2/+1
flags local variable in __mkroute_input is not used as a variable. Signed-off-by: Masatake YAMATO <yamato@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-24net: ipv4 sysctl option to ignore routes when nexthop link is downAndy Gospodarek1-5/+5
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>
2015-05-23Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-0/+4
Conflicts: drivers/net/ethernet/cadence/macb.c drivers/net/phy/phy.c include/linux/skbuff.h net/ipv4/tcp.c net/switchdev/switchdev.c Switchdev was a case of RTNH_H_{EXTERNAL --> OFFLOAD} renaming overlapping with net-next changes of various sorts. phy.c was a case of two changes, one adding a local variable to a function whilst the second was removing one. tcp.c overlapped a deadlock fix with the addition of new tcp_info statistic values. macb.c involved the addition of two zyncq device entries. skbuff.h involved adding back ipv4_daddr to nf_bridge_info whilst net-next changes put two other existing members of that struct into a union. Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-22ipv4: Avoid crashing in ip_errorEric W. Biederman1-0/+4
ip_error does not check if in_dev is NULL before dereferencing it. IThe following sequence of calls is possible: CPU A CPU B ip_rcv_finish ip_route_input_noref() ip_route_input_slow() inetdev_destroy() dst_input() With the result that a network device can be destroyed while processing an input packet. A crash was triggered with only unicast packets in flight, and forwarding enabled on the only network device. The error condition was created by the removal of the network device. As such it is likely the that error code was -EHOSTUNREACH, and the action taken by ip_error (if in_dev had been accessible) would have been to not increment any counters and to have tried and likely failed to send an icmp error as the network device is going away. Therefore handle this weird case by just dropping the packet if !in_dev. It will result in dropping the packet sooner, and will not result in an actual change of behavior. Fixes: 251da4130115b ("ipv4: Cache ip_error() routes even when not forwarding.") Reported-by: Vittorio Gambaletta <linuxbugs@vittgam.net> Tested-by: Vittorio Gambaletta <linuxbugs@vittgam.net> Signed-off-by: Vittorio Gambaletta <linuxbugs@vittgam.net> 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>
2015-05-04net: ipv4: route: Fix sending IGMP messages with link addressAndrew Lunn1-1/+2
In setups with a global scope address on an interface, and a lesser scope address on an interface sending IGMP reports, the reports can be sent using the other interfaces global scope address rather than the local interface address. RFC 2236 suggests: Ignore the Report if you cannot identify the source address of the packet as belonging to a subnet assigned to the interface on which the packet was received. since such reports could be forged. Look at the protocol when deciding if a RT_SCOPE_LINK address should be used for the packet. Signed-off-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-03Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-4/+1
Merge net into net-next. Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-02ipv4: speedup ip_idents_reserve()Eric Dumazet1-9/+11
Under stress, ip_idents_reserve() is accessing a contended cache line twice, with non optimal MESI transactions. If we place timestamps in separate location, we reduce this pressure by ~50% and allow atomic_add_return() to issue a Request for Ownership. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-29route: Use ipv4_mtu instead of raw rt_pmtuHerbert Xu1-4/+1
The commit 3cdaa5be9e81a914e633a6be7b7d2ef75b528562 ("ipv4: Don't increase PMTU with Datagram Too Big message") broke PMTU in cases where the rt_pmtu value has expired but is smaller than the new PMTU value. This obsolete rt_pmtu then prevents the new PMTU value from being installed. Fixes: 3cdaa5be9e81 ("ipv4: Don't increase PMTU with Datagram Too Big message") Reported-by: Gerd v. Egidy <gerd.von.egidy@intra2net.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-03ipv4: coding style: comparison for inequality with NULLIan Morris1-1/+1
The ipv4 code uses a mixture of coding styles. In some instances check for non-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>
2015-04-03ipv4: coding style: comparison for equality with NULLIan Morris1-10/+10
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 Benc1-2/+2
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 Benc1-4/+4
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>
2015-03-25ipv4: hash net ptr into fragmentation bucket selectionHannes Frederic Sowa1-2/+2
As namespaces are sometimes used with overlapping ip address ranges, we should also use the namespace as input to the hash to select the ip fragmentation counter bucket. Cc: Eric Dumazet <edumazet@google.com> Cc: Flavio Leitner <fbl@redhat.com> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-09net: Remove protocol from struct dst_opsEric W. Biederman1-2/+0
After my change to neigh_hh_init to obtain the protocol from the neigh_table there are no more users of protocol in struct dst_ops. Remove the protocol field from dst_ops and all of it's initializers. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-02-06Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-0/+3
Conflicts: drivers/net/vxlan.c drivers/vhost/net.c include/linux/if_vlan.h net/core/dev.c The net/core/dev.c conflict was the overlap of one commit marking an existing function static whilst another was adding a new function. In the include/linux/if_vlan.h case, the type used for a local variable was changed in 'net', whereas the function got rewritten to fix a stacked vlan bug in 'net-next'. In drivers/vhost/net.c, Al Viro's iov_iter conversions in 'net-next' overlapped with an endainness fix for VHOST 1.0 in 'net'. In drivers/net/vxlan.c, vxlan_find_vni() added a 'flags' parameter in 'net-next' whereas in 'net' there was a bug fix to pass in the correct network namespace pointer in calls to this function. Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-30ipv4: Don't increase PMTU with Datagram Too Big message.Li Wei1-0/+3
RFC 1191 said, "a host MUST not increase its estimate of the Path MTU in response to the contents of a Datagram Too Big message." Signed-off-by: Li Wei <lw@cn.fujitsu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-28Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-4/+5
Conflicts: arch/arm/boot/dts/imx6sx-sdb.dts net/sched/cls_bpf.c Two simple sets of overlapping changes. Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-27ipv4: try to cache dst_entries which would cause a redirectHannes Frederic Sowa1-4/+5
Not caching dst_entries which cause redirects could be exploited by hosts on the same subnet, causing a severe DoS attack. This effect aggravated since commit f88649721268999 ("ipv4: fix dst race in sk_dst_get()"). Lookups causing redirects will be allocated with DST_NOCACHE set which will force dst_release to free them via RCU. Unfortunately waiting for RCU grace period just takes too long, we can end up with >1M dst_entries waiting to be released and the system will run OOM. rcuos threads cannot catch up under high softirq load. Attaching the flag to emit a redirect later on to the specific skb allows us to cache those dst_entries thus reducing the pressure on allocation and deallocation. This issue was discovered by Marcelo Leitner. Cc: Julian Anastasov <ja@ssi.bg> Signed-off-by: Marcelo Leitner <mleitner@redhat.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-19netlink: Fix bugs in nlmsg_end() conversions.David S. Miller1-1/+1
Commit 053c095a82cf ("netlink: make nlmsg_end() and genlmsg_end() void") didn't catch all of the cases where callers were breaking out on the return value being equal to zero, which they no longer should when zero means success. Fix all such cases. Reported-by: Marcel Holtmann <marcel@holtmann.org> Reported-by: Scott Feldman <sfeldma@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-18netlink: make nlmsg_end() and genlmsg_end() voidJohannes Berg1-1/+2
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>
2015-01-16ipv4: per cpu uncached listEric Dumazet1-13/+33
RAW sockets with hdrinc suffer from contention on rt_uncached_lock spinlock. One solution is to use percpu lists, since most routes are destroyed by the cpu that created them. It is unclear why we even have to put these routes in uncached_list, as all outgoing packets should be freed when a device is dismantled. Signed-off-by: Eric Dumazet <edumazet@google.com> Fixes: caacf05e5ad1 ("ipv4: Properly purge netdev references on uncached routes.") Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-31ipv4: Do not cache routing failures due to disabled forwarding.Nicolas Cavallari1-0/+1
If we cache them, the kernel will reuse them, independently of whether forwarding is enabled or not. Which means that if forwarding is disabled on the input interface where the first routing request comes from, then that unreachable result will be cached and reused for other interfaces, even if forwarding is enabled on them. The opposite is also true. This can be verified with two interfaces A and B and an output interface C, where B has forwarding enabled, but not A and trying ip route get $dst iif A from $src && ip route get $dst iif B from $src Signed-off-by: Nicolas Cavallari <nicolas.cavallari@green-communications.fr> Reviewed-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-15Merge branch 'for-3.18-consistent-ops' of ↵Linus Torvalds1-2/+2
git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu Pull percpu consistent-ops changes from Tejun Heo: "Way back, before the current percpu allocator was implemented, static and dynamic percpu memory areas were allocated and handled separately and had their own accessors. The distinction has been gone for many years now; however, the now duplicate two sets of accessors remained with the pointer based ones - this_cpu_*() - evolving various other operations over time. During the process, we also accumulated other inconsistent operations. This pull request contains Christoph's patches to clean up the duplicate accessor situation. __get_cpu_var() uses are replaced with with this_cpu_ptr() and __this_cpu_ptr() with raw_cpu_ptr(). Unfortunately, the former sometimes is tricky thanks to C being a bit messy with the distinction between lvalues and pointers, which led to a rather ugly solution for cpumask_var_t involving the introduction of this_cpu_cpumask_var_ptr(). This converts most of the uses but not all. Christoph will follow up with the remaining conversions in this merge window and hopefully remove the obsolete accessors" * 'for-3.18-consistent-ops' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (38 commits) irqchip: Properly fetch the per cpu offset percpu: Resolve ambiguities in __get_cpu_var/cpumask_var_t -fix ia64: sn_nodepda cannot be assigned to after this_cpu conversion. Use __this_cpu_write. percpu: Resolve ambiguities in __get_cpu_var/cpumask_var_t Revert "powerpc: Replace __get_cpu_var uses" percpu: Remove __this_cpu_ptr clocksource: Replace __this_cpu_ptr with raw_cpu_ptr sparc: Replace __get_cpu_var uses avr32: Replace __get_cpu_var with __this_cpu_write blackfin: Replace __get_cpu_var uses tile: Use this_cpu_ptr() for hardware counters tile: Replace __get_cpu_var uses powerpc: Replace __get_cpu_var uses alpha: Replace __get_cpu_var ia64: Replace __get_cpu_var uses s390: cio driver &__get_cpu_var replacements s390: Replace __get_cpu_var uses mips: Replace __get_cpu_var uses MIPS: Replace __get_cpu_var uses in FPU emulator. arm: Replace __this_cpu_ptr with raw_cpu_ptr ...
2014-10-02Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-1/+1
Conflicts: drivers/net/usb/r8152.c net/netfilter/nfnetlink.c Both r8152 and nfnetlink conflicts were simple overlapping changes. Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-29neigh: check error pointer instead of NULL for ipv4_neigh_lookup()WANG Cong1-1/+1
Fixes: commit f187bc6efb7250afee0e2009b6106 ("ipv4: No need to set generic neighbour pointer") Cc: David S. Miller <davem@davemloft.net> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-23Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-3/+3
Conflicts: arch/mips/net/bpf_jit.c drivers/net/can/flexcan.c Both the flexcan and MIPS bpf_jit conflicts were cases of simple overlapping changes. Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-16xfrm: Generate blackhole routes only from route lookup functionsSteffen Klassert1-3/+3
Currently we genarate a blackhole route route whenever we have matching policies but can not resolve the states. Here we assume that dst_output() is called to kill the balckholed packets. Unfortunately this assumption is not true in all cases, so it is possible that these packets leave the system unwanted. We fix this by generating blackhole routes only from the route lookup functions, here we can guarantee a call to dst_output() afterwards. Fixes: 2774c131b1d ("xfrm: Handle blackhole route creation via afinfo.") Reported-by: Konstantinos Kolelis <k.kolelis@sirrix.com> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2014-09-06ipv4: harden fnhe_hashfun()Eric Dumazet1-4/+4
Lets make this hash function a bit secure, as ICMP attacks are still in the wild. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-06ipv4: fix a race in update_or_create_fnhe()Eric Dumazet1-3/+3
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>
2014-08-26net: Replace get_cpu_var through this_cpu_ptrChristoph Lameter1-2/+2
Replace uses of get_cpu_var for address calculation through this_cpu_ptr. Cc: netdev@vger.kernel.org Cc: Eric Dumazet <edumazet@google.com> Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Christoph Lameter <cl@linux.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2014-08-08ipv4: removed redundant conditionalNiv Yehezkel1-2/+0
Since fib_lookup cannot return ESRCH no longer, checking for this error code is no longer neccesary. Signed-off-by: Niv Yehezkel <executerx@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-29ip: make IP identifiers less predictableEric Dumazet1-3/+29
In "Counting Packets Sent Between Arbitrary Internet Hosts", Jeffrey and Jedidiah describe ways exploiting linux IP identifier generation to infer whether two machines are exchanging packets. With commit 73f156a6e8c1 ("inetpeer: get rid of ip_id_count"), we changed IP id generation, but this does not really prevent this side-channel technique. This patch adds a random amount of perturbation so that IP identifiers for a given destination [1] are no longer monotonically increasing after an idle period. Note that prandom_u32_max(1) returns 0, so if generator is used at most once per jiffy, this patch inserts no hole in the ID suite and do not increase collision probability. This is jiffies based, so in the worst case (HZ=1000), the id can rollover after ~65 seconds of idle time, which should be fine. We also change the hash used in __ip_select_ident() to not only hash on daddr, but also saddr and protocol, so that ICMP probes can not be used to infer information for other protocols. For IPv6, adds saddr into the hash as well, but not nexthdr. If I ping the patched target, we can see ID are now hard to predict. 21:57:11.008086 IP (...) A > target: ICMP echo request, seq 1, length 64 21:57:11.010752 IP (... id 2081 ...) target > A: ICMP echo reply, seq 1, length 64 21:57:12.013133 IP (...) A > target: ICMP echo request, seq 2, length 64 21:57:12.015737 IP (... id 3039 ...) target > A: ICMP echo reply, seq 2, length 64 21:57:13.016580 IP (...) A > target: ICMP echo request, seq 3, length 64 21:57:13.019251 IP (... id 3437 ...) target > A: ICMP echo reply, seq 3, length 64 [1] TCP sessions uses a per flow ID generator not changed by this patch. Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Jeffrey Knockel <jeffk@cs.unm.edu> Reported-by: Jedidiah R. Crandall <crandall@cs.unm.edu> Cc: Willy Tarreau <w@1wt.eu> Cc: Hannes Frederic Sowa <hannes@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-01ipv4: irq safe sk_dst_[re]set() and ipv4_sk_update_pmtu() fixEric Dumazet1-7/+8
We have two different ways to handle changes to sk->sk_dst First way (used by TCP) assumes socket lock is owned by caller, and use no extra lock : __sk_dst_set() & __sk_dst_reset() Another way (used by UDP) uses sk_dst_lock because socket lock is not always taken. Note that sk_dst_lock is not softirq safe. These ways are not inter changeable for a given socket type. ipv4_sk_update_pmtu(), added in linux-3.8, added a race, as it used the socket lock as synchronization, but users might be UDP sockets. Instead of converting sk_dst_lock to a softirq safe version, use xchg() as we did for sk_rx_dst in commit e47eb5dfb296b ("udp: ipv4: do not use sk_dst_lock from softirq context") In a follow up patch, we probably can remove sk_dst_lock, as it is only used in IPv6. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Steffen Klassert <steffen.klassert@secunet.com> Fixes: 9cb3a50c5f63e ("ipv4: Invalidate the socket cached route on pmtu events if possible") Signed-off-by: David S. Miller <davem@davemloft.net>
2014-06-02inetpeer: get rid of ip_id_countEric Dumazet1-29/+16
Ideally, we would need to generate IP ID using a per destination IP generator. linux kernels used inet_peer cache for this purpose, but this had a huge cost on servers disabling MTU discovery. 1) each inet_peer struct consumes 192 bytes 2) inetpeer cache uses a binary tree of inet_peer structs, with a nominal size of ~66000 elements under load. 3) lookups in this tree are hitting a lot of cache lines, as tree depth is about 20. 4) If server deals with many tcp flows, we have a high probability of not finding the inet_peer, allocating a fresh one, inserting it in the tree with same initial ip_id_count, (cf secure_ip_id()) 5) We garbage collect inet_peer aggressively. IP ID generation do not have to be 'perfect' Goal is trying to avoid duplicates in a short period of time, so that reassembly units have a chance to complete reassembly of fragments belonging to one message before receiving other fragments with a recycled ID. We simply use an array of generators, and a Jenkin hash using the dst IP as a key. ipv6_select_ident() is put back into net/ipv6/ip6_output.c where it belongs (it is only used from this file) secure_ip_id() and secure_ipv6_id() no longer are needed. Rename ip_select_ident_more() to ip_select_ident_segs() to avoid unnecessary decrement/increment of the number of segments. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-05-24Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-1/+1
Conflicts: drivers/net/bonding/bond_alb.c drivers/net/ethernet/altera/altera_msgdma.c drivers/net/ethernet/altera/altera_sgdma.c net/ipv6/xfrm6_output.c Several cases of overlapping changes. The xfrm6_output.c has a bug fix which overlaps the renaming of skb->local_df to skb->ignore_df. In the Altera TSE driver cases, the register access cleanups in net-next overlapped with bug fixes done in net. Similarly a bug fix to send ALB packets in the bonding driver using the right source address overlaps with cleanups in net-next. Signed-off-by: David S. Miller <davem@davemloft.net>
2014-05-22ipv4: initialise the itag variable in __mkroute_inputLi RongQing1-1/+1
the value of itag is a random value from stack, and may not be initiated by fib_validate_source, which called fib_combine_itag if CONFIG_IP_ROUTE_CLASSID is not set This will make the cached dst uncertainty Signed-off-by: Li RongQing <roy.qing.li@gmail.com> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-05-14net: Use fwmark reflection in PMTU discovery.Lorenzo Colitti1-0/+7
Currently, routing lookups used for Path PMTU Discovery in absence of a socket or on unmarked sockets use a mark of 0. This causes PMTUD not to work when using routing based on netfilter fwmark mangling and fwmark ip rules, such as: iptables -j MARK --set-mark 17 ip rule add fwmark 17 lookup 100 This patch causes these route lookups to use the fwmark from the received ICMP error when the fwmark_reflect sysctl is enabled. This allows the administrator to make PMTUD work by configuring appropriate fwmark rules to mark the inbound ICMP packets. Black-box tested using user-mode linux by pointing different fwmarks at routing tables egressing on different interfaces, and using iptables mangling to mark packets inbound on each interface with the interface's fwmark. ICMPv4 and ICMPv6 PMTU discovery work as expected when mark reflection is enabled and fail when it is disabled. Signed-off-by: Lorenzo Colitti <lorenzo@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-04-16ipv4, route: pass 0 instead of LOOPBACK_IFINDEX to fib_validate_source()Cong Wang1-2/+1
In my special case, when a packet is redirected from veth0 to lo, its skb->dev->ifindex would be LOOPBACK_IFINDEX. Meanwhile we pass the hard-coded LOOPBACK_IFINDEX to fib_validate_source() in ip_route_input_slow(). This would cause the following check in fib_validate_source() fail: (dev->ifindex != oif || !IN_DEV_TX_REDIRECTS(idev)) when rp_filter is disabeld on loopback. As suggested by Julian, the caller should pass 0 here so that we will not end up by calling __fib_validate_source(). 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>
2014-04-15ipv4: add a sock pointer to dst->output() path.Eric Dumazet1-2/+2
In the dst->output() path for ipv4, the code assumes the skb it has to transmit is attached to an inet socket, specifically via ip_mc_output() : The sk_mc_loop() test triggers a WARN_ON() when the provider of the packet is an AF_PACKET socket. The dst->output() method gets an additional 'struct sock *sk' parameter. This needs a cascade of changes so that this parameter can be propagated from vxlan to final consumer. Fixes: 8f646c922d55 ("vxlan: keep original skb ownership") Reported-by: lucien xin <lucien.xin@gmail.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-04-14ipv4: return valid RTA_IIF on ip route getJulian Anastasov1-1/+1
Extend commit 13378cad02afc2adc6c0e07fca03903c7ada0b37 ("ipv4: Change rt->rt_iif encoding.") from 3.6 to return valid RTA_IIF on 'ip route get ... iif DEVICE' instead of rt_iif 0 which is displayed as 'iif *'. inet_iif is not appropriate to use because skb_iif is not set. Use the skb->dev->ifindex instead. Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-04-08net: replace __this_cpu_inc in route.c with raw_cpu_incChristoph Lameter1-1/+1
The RT_CACHE_STAT_INC macro triggers the new preemption checks for __this_cpu ops. I do not see any other synchronization that would allow the use of a __this_cpu operation here however in commit dbd2915ce87e ("[IPV4]: RT_CACHE_STAT_INC() warning fix") Andrew justifies the use of raw_smp_processor_id() here because "we do not care" about races. In the past we agreed that the price of disabling interrupts here to get consistent counters would be too high. These counters may be inaccurate due to race conditions. The use of __this_cpu op improves the situation already from what commit dbd2915ce87e did since the single instruction emitted on x86 does not allow the race to occur anymore. However, non x86 platforms could still experience a race here. Trace: __this_cpu_add operation in preemptible [00000000] code: avahi-daemon/1193 caller is __this_cpu_preempt_check+0x38/0x60 CPU: 1 PID: 1193 Comm: avahi-daemon Tainted: GF 3.12.0-rc4+ #187 Call Trace: check_preemption_disabled+0xec/0x110 __this_cpu_preempt_check+0x38/0x60 __ip_route_output_key+0x575/0x8c0 ip_route_output_flow+0x27/0x70 udp_sendmsg+0x825/0xa20 inet_sendmsg+0x85/0xc0 sock_sendmsg+0x9c/0xd0 ___sys_sendmsg+0x37c/0x390 __sys_sendmsg+0x49/0x90 SyS_sendmsg+0x12/0x20 tracesys+0xe1/0xe6 Signed-off-by: Christoph Lameter <cl@linux.com> Acked-by: David S. Miller <davem@davemloft.net> Acked-by: Ingo Molnar <mingo@kernel.org> Cc: Eric Dumazet <edumazet@google.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-03-24ipv4: remove ip_rt_dump from route.cLi RongQing1-5/+0
ip_rt_dump do nothing after IPv4 route caches removal, so we can remove it. Signed-off-by: Li RongQing <roy.qing.li@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-24ipv4: remove ipv4_ifdown_dst from route.cLi RongQing1-6/+0
ipv4_ifdown_dst does nothing after IPv4 route caches removal, so we can remove it. Signed-off-by: Li RongQing <roy.qing.li@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-02-19Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-4/+9
Conflicts: drivers/net/bonding/bond_3ad.h drivers/net/bonding/bond_main.c Two minor conflicts in bonding, both of which were overlapping changes. Signed-off-by: David S. Miller <davem@davemloft.net>
2014-02-18ipv4: fix counter in_slow_totDuan Jiong1-2/+2
since commit 89aef8921bf("ipv4: Delete routing cache."), the counter in_slow_tot can't work correctly. The counter in_slow_tot increase by one when fib_lookup() return successfully in ip_route_input_slow(), but actually the dst struct maybe not be created and cached, so we can increase in_slow_tot after the dst struct is created. Signed-off-by: Duan Jiong <duanj.fnst@cn.fujitsu.com> Signed-off-by: David S. Miller <davem@davemloft.net>