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path: root/net/ipv4/tcp_metrics.c
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2015-04-07tcp: RFC7413 option support for Fast Open clientDaniel Lee
Fast Open has been using an experimental option with a magic number (RFC6994). This patch makes the client by default use the RFC7413 option (34) to get and send Fast Open cookies. This patch makes the client solicit cookies from a given server first with the RFC7413 option. If that fails to elicit a cookie, then it tries the RFC6994 experimental option. If that also fails, it uses the RFC7413 option on all subsequent connect attempts. If the server returns a Fast Open cookie then the client caches the form of the option that successfully elicited a cookie, and uses that form on later connects when it presents that cookie. The idea is to gradually obsolete the use of experimental options as the servers and clients upgrade, while keeping the interoperability meanwhile. Signed-off-by: Daniel Lee <Longinus00@gmail.com> Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.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>
2015-03-31tcp: simplify inetpeer_addr_base useJiri Benc
In many places, the a6 field is typecasted to struct in6_addr. As the fields are in union anyway, just add in6_addr type to the union and get rid of the typecasting. Signed-off-by: Jiri Benc <jbenc@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-16tcp_metrics: fix wrong lockdep annotationsEric Dumazet
Changes in tcp_metric hash table are protected by tcp_metrics_lock only, not by genl_mutex While we are at it use deref_locked() instead of rcu_dereference() in tcp_new() to avoid unnecessary barrier, as we hold tcp_metrics_lock as well. Reported-by: Andrew Vagin <avagin@parallels.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Fixes: 098a697b497e ("tcp_metrics: Use a single hash table for all network namespaces.") Reviewed-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-13tcp_metrics: Use a single hash table for all network namespaces.Eric W. Biederman
Now that all of the operations are safe on a single hash table accross network namespaces, allocate a single global hash table and update the code to use it. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-13tcp_metrics: Rewrite tcp_metrics_flush_allEric W. Biederman
Rewrite tcp_metrics_flush_all so that it can cope with entries from different network namespaces on it's hash chain. This is based on the logic in tcp_metrics_nl_cmd_del for deleting a selection of entries from a tcp metrics hash chain. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-13tcp_metrics: Remove the unused return code from tcp_metrics_flush_allEric W. Biederman
tcp_metrics_flush_all always returns 0. Remove the unnecessary return code. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-13tcp_metrics: Add a field tcpm_net and verify it matches on lookupEric W. Biederman
In preparation for using one tcp metrics hash table for all network namespaces add a field tcpm_net to struct tcp_metrics_block, and verify that field on all hash table lookups. Make the field tcpm_net of type possible_net_t so it takes no space when network namespaces are disabled. Further add a function tm_net to read that field so we can be efficient when network namespaces are disabled and concise the rest of the time. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-13tcp_metrics: Mix the network namespace into the hash function.Eric W. Biederman
In preparation for using one hash table for all network namespaces mix the network namespace into the hash value. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-13tcp_metrics: panic when tcp_metrics_init fails.Eric W. Biederman
There is not a practical way to cleanup during boot so just panic if there is a problem initializing tcp_metrics. That will at least give us a clear place to start debugging if something does go wrong. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.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>
2014-08-14tcp: don't allow syn packets without timestamps to pass tcp_tw_recycle logicHannes Frederic Sowa
tcp_tw_recycle heavily relies on tcp timestamps to build a per-host ordering of incoming connections and teardowns without the need to hold state on a specific quadruple for TCP_TIMEWAIT_LEN, but only for the last measured RTO. To do so, we keep the last seen timestamp in a per-host indexed data structure and verify if the incoming timestamp in a connection request is strictly greater than the saved one during last connection teardown. Thus we can verify later on that no old data packets will be accepted by the new connection. During moving a socket to time-wait state we already verify if timestamps where seen on a connection. Only if that was the case we let the time-wait socket expire after the RTO, otherwise normal TCP_TIMEWAIT_LEN will be used. But we don't verify this on incoming SYN packets. If a connection teardown was less than TCP_PAWS_MSL seconds in the past we cannot guarantee to not accept data packets from an old connection if no timestamps are present. We should drop this SYN packet. This patch closes this loophole. Please note, this patch does not make tcp_tw_recycle in any way more usable but only adds another safety check: Sporadic drops of SYN packets because of reordering in the network or in the socket backlog queues can happen. Users behing NAT trying to connect to a tcp_tw_recycle enabled server can get caught in blackholes and their connection requests may regullary get dropped because hosts behind an address translator don't have synchronized tcp timestamp clocks. tcp_tw_recycle cannot work if peers don't have tcp timestamps enabled. In general, use of tcp_tw_recycle is disadvised. Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Florian Westphal <fw@strlen.de> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-31tcp: don't require root to read tcp_metricsBanerjee, Debabrata
commit d23ff7016 (tcp: add generic netlink support for tcp_metrics) introduced netlink support for the new tcp_metrics, however it restricted getting of tcp_metrics to root user only. This is a change from how these values could have been fetched when in the old route cache. Unless there's a legitimate reason to restrict the reading of these values it would be better if normal users could fetch them. Cc: Julian Anastasov <ja@ssi.bg> Cc: linux-kernel@vger.kernel.org Signed-off-by: Debabrata Banerjee <dbanerje@akamai.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-06-05net: use the new API kvfree()WANG Cong
It is available since v3.15-rc5. Cc: Pablo Neira Ayuso <pablo@netfilter.org> 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>
2014-02-26tcp: switch rtt estimations to usec resolutionEric Dumazet
Upcoming congestion controls for TCP require usec resolution for RTT estimations. Millisecond resolution is simply not enough these days. FQ/pacing in DC environments also require this change for finer control and removal of bimodal behavior due to the current hack in tcp_update_pacing_rate() for 'small rtt' TCP_CONG_RTT_STAMP is no longer needed. As Julian Anastasov pointed out, we need to keep user compatibility : tcp_metrics used to export RTT and RTTVAR in msec resolution, so we added RTT_US and RTTVAR_US. An iproute2 patch is needed to use the new attributes if provided by the kernel. In this example ss command displays a srtt of 32 usecs (10Gbit link) lpk51:~# ./ss -i dst lpk52 Netid State Recv-Q Send-Q Local Address:Port Peer Address:Port tcp ESTAB 0 1 10.246.11.51:42959 10.246.11.52:64614 cubic wscale:6,6 rto:201 rtt:0.032/0.001 ato:40 mss:1448 cwnd:10 send 3620.0Mbps pacing_rate 7240.0Mbps unacked:1 rcv_rtt:993 rcv_space:29559 Updated iproute2 ip command displays : lpk51:~# ./ip tcp_metrics | grep 10.246.11.52 10.246.11.52 age 561.914sec cwnd 10 rtt 274us rttvar 213us source 10.246.11.51 Old binary displays : lpk51:~# ip tcp_metrics | grep 10.246.11.52 10.246.11.52 age 561.914sec cwnd 10 rtt 250us rttvar 125us source 10.246.11.51 With help from Julian Anastasov, Stephen Hemminger and Yuchung Cheng Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Cc: Stephen Hemminger <stephen@networkplumber.org> Cc: Yuchung Cheng <ycheng@google.com> Cc: Larry Brakmo <brakmo@google.com> Cc: Julian Anastasov <ja@ssi.bg> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-23tcp: metrics: Handle v6/v4-mapped sockets in tcp-metricsChristoph Paasch
A socket may be v6/v4-mapped. In that case sk->sk_family is AF_INET6, but the IP being used is actually an IPv4-address. Current's tcp-metrics will thus represent it as an IPv6-address: root@server:~# ip tcp_metrics ::ffff:10.1.1.2 age 22.920sec rtt 18750us rttvar 15000us cwnd 10 10.1.1.2 age 47.970sec rtt 16250us rttvar 10000us cwnd 10 This patch modifies the tcp-metrics so that they are able to handle the v6/v4-mapped sockets correctly. Signed-off-by: Christoph Paasch <christoph.paasch@uclouvain.be> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-22tcp: metrics: Fix rcu-race when deleting multiple entriesChristoph Paasch
In bbf852b96ebdc6d1 I introduced the tmlist, which allows to delete multiple entries from the cache that match a specified destination if no source-IP is specified. However, as the cache is an RCU-list, we should not create this tmlist, as it will change the tcpm_next pointer of the element that will be deleted and so a thread iterating over the cache's entries while holding the RCU-lock might get "redirected" to this tmlist. This patch fixes this, by reverting back to the old behavior prior to bbf852b96ebdc6d1, which means that we simply change the tcpm_next pointer of the previous element (pp) to jump over the one we are deleting. The difference is that we call kfree_rcu() directly on the cache entry, which allows us to delete multiple entries from the list. Fixes: bbf852b96ebdc6d1 (tcp: metrics: Delete all entries matching a certain destination) Signed-off-by: Christoph Paasch <christoph.paasch@uclouvain.be> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-18Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Conflicts: drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c net/ipv4/tcp_metrics.c Overlapping changes between the "don't create two tcp metrics objects with the same key" race fix in net and the addition of the destination address in the lookup key in net-next. Minor overlapping changes in bnx2x driver. Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-17tcp: metrics: Avoid duplicate entries with the same destination-IPChristoph Paasch
Because the tcp-metrics is an RCU-list, it may be that two soft-interrupts are inside __tcp_get_metrics() for the same destination-IP at the same time. If this destination-IP is not yet part of the tcp-metrics, both soft-interrupts will end up in tcpm_new and create a new entry for this IP. So, we will have two tcp-metrics with the same destination-IP in the list. This patch checks twice __tcp_get_metrics(). First without holding the lock, then while holding the lock. The second one is there to confirm that the entry has not been added by another soft-irq while waiting for the spin-lock. Fixes: 51c5d0c4b169b (tcp: Maintain dynamic metrics in local cache.) Signed-off-by: Christoph Paasch <christoph.paasch@uclouvain.be> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-10tcp: metrics: Allow selective get/del of tcp-metrics based on src IPChristoph Paasch
We want to be able to get/del tcp-metrics based on the src IP. This patch adds the necessary parsing of the netlink attribute and if the source address is set, it will match on this one too. Signed-off-by: Christoph Paasch <christoph.paasch@uclouvain.be> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-10tcp: metrics: Delete all entries matching a certain destinationChristoph Paasch
As we now can have multiple entries per destination-IP, the "ip tcp_metrics delete address ADDRESS" command deletes all of them. Signed-off-by: Christoph Paasch <christoph.paasch@uclouvain.be> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-10tcp: metrics: New netlink attribute for src IP and dumped in netlink replyChristoph Paasch
This patch adds a new netlink attribute for the source-IP and appends it to the netlink reply. Now, iproute2 can have access to the source-IP. Signed-off-by: Christoph Paasch <christoph.paasch@uclouvain.be> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-10tcp: metrics: Add source-address to tcp-metricsChristoph Paasch
We add the source-address to the tcp-metrics, so that different metrics will be used per source/destination-pair. We use the destination-hash to store the metric inside the hash-table. That way, deleting and dumping via "ip tcp_metrics" is easy. Signed-off-by: Christoph Paasch <christoph.paasch@uclouvain.be> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-10tcp: metrics: rename tcpm_addr to tcpm_daddrChristoph Paasch
As we will add also the source-address, we rename all accesses to the tcp-metrics address to use "daddr". Signed-off-by: Christoph Paasch <christoph.paasch@uclouvain.be> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-19genetlink: only pass array to genl_register_family_with_ops()Johannes Berg
As suggested by David Miller, make genl_register_family_with_ops() a macro and pass only the array, evaluating ARRAY_SIZE() in the macro, this is a little safer. The openvswitch has some indirection, assing ops/n_ops directly in that code. This might ultimately just assign the pointers in the family initializations, saving the struct genl_family_and_ops and code (once mcast groups are handled differently.) Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-14genetlink: make all genl_ops users constJohannes Berg
Now that genl_ops are no longer modified in place when registering, they can be made const. This patch was done mostly with spatch: @@ identifier ops; @@ +const struct genl_ops ops[] = { ... }; (except the struct thing in net/openvswitch/datapath.c) Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-14net-tcp: fix panic in tcp_fastopen_cache_set()Eric Dumazet
We had some reports of crashes using TCP fastopen, and Dave Jones gave a nice stack trace pointing to the error. Issue is that tcp_get_metrics() should not be called with a NULL dst Fixes: 1fe4c481ba637 ("net-tcp: Fast Open client - cookie cache") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Dave Jones <davej@redhat.com> Cc: Yuchung Cheng <ycheng@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Tested-by: Dave Jones <davej@fedoraproject.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-29tcp: temporarily disable Fast Open on SYN timeoutYuchung Cheng
Fast Open currently has a fall back feature to address SYN-data being dropped but it requires the middle-box to pass on regular SYN retry after SYN-data. This is implemented in commit aab487435 ("net-tcp: Fast Open client - detecting SYN-data drops") However some NAT boxes will drop all subsequent packets after first SYN-data and blackholes the entire connections. An example is in commit 356d7d8 "netfilter: nf_conntrack: fix tcp_in_window for Fast Open". The sender should note such incidents and fall back to use the regular TCP handshake on subsequent attempts temporarily as well: after the second SYN timeouts the original Fast Open SYN is most likely lost. When such an event recurs Fast Open is disabled based on the number of recurrences exponentially. Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-10inet: includes a sock_common in request_sockEric Dumazet
TCP listener refactoring, part 5 : We want to be able to insert request sockets (SYN_RECV) into main ehash table instead of the per listener hash table to allow RCU lookups and remove listener lock contention. This patch includes the needed struct sock_common in front of struct request_sock This means there is no more inet6_request_sock IPv6 specific structure. Following inet_request_sock fields were renamed as they became macros to reference fields from struct sock_common. Prefix ir_ was chosen to avoid name collisions. loc_port -> ir_loc_port loc_addr -> ir_loc_addr rmt_addr -> ir_rmt_addr rmt_port -> ir_rmt_port iif -> ir_iif Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-09net: fix build errors if ipv6 is disabledEric Dumazet
CONFIG_IPV6=n is still a valid choice ;) It appears we can remove dead code. Reported-by: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-09ipv6: make lookups simpler and fasterEric Dumazet
TCP listener refactoring, part 4 : To speed up inet lookups, we moved IPv4 addresses from inet to struct sock_common Now is time to do the same for IPv6, because it permits us to have fast lookups for all kind of sockets, including upcoming SYN_RECV. Getting IPv6 addresses in TCP lookups currently requires two extra cache lines, plus a dereference (and memory stall). inet6_sk(sk) does the dereference of inet_sk(__sk)->pinet6 This patch is way bigger than its IPv4 counter part, because for IPv4, we could add aliases (inet_daddr, inet_rcv_saddr), while on IPv6, it's not doable easily. inet6_sk(sk)->daddr becomes sk->sk_v6_daddr inet6_sk(sk)->rcv_saddr becomes sk->sk_v6_rcv_saddr And timewait socket also have tw->tw_v6_daddr & tw->tw_v6_rcv_saddr at the same offset. We get rid of INET6_TW_MATCH() as INET6_MATCH() is now the generic macro. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-17tcp: fix RTO calculated from cached RTTNeal Cardwell
Commit 1b7fdd2ab5852 ("tcp: do not use cached RTT for RTT estimation") did not correctly account for the fact that crtt is the RTT shifted left 3 bits. Fix the calculation to consistently reflect this fact. Signed-off-by: Neal Cardwell <ncardwell@google.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Yuchung Cheng <ycheng@google.com> Acked-by: Eric Dumazet <edumazet@google.com> Acked-By: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-04tcp: better comments for RTO initiallizationYuchung Cheng
Commit 1b7fdd2ab585("tcp: do not use cached RTT for RTT estimation") removes important comments on how RTO is initialized and updated. Hopefully this patch puts those information back. Signed-off-by: Yuchung Cheng <ycheng@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-30tcp: do not use cached RTT for RTT estimationYuchung Cheng
RTT cached in the TCP metrics are valuable for the initial timeout because SYN RTT usually does not account for serialization delays on low BW path. However using it to seed the RTT estimator maybe disruptive because other components (e.g., pacing) require the smooth RTT to be obtained from actual connection. The solution is to use the higher cached RTT to set the first RTO conservatively like tcp_rtt_estimator(), but avoid seeding the other RTT estimator variables such as srtt. It is also a good idea to keep RTO conservative to obtain the first RTT sample, and the performance is insured by TCP loss probe if SYN RTT is available. To keep the seeding formula consistent across SYN RTT and cached RTT, the rttvar is twice the cached RTT instead of cached RTTVAR value. The reason is because cached variation may be too small (near min RTO) which defeats the purpose of being conservative on first RTO. However the metrics still keep the RTT variations as they might be useful for user applications (through ip). Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Tested-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-05-05tcp: do not expire TCP fastopen cookiesEric Dumazet
TCP metric cache expires entries after one hour. This probably make sense for TCP RTT/RTTVAR/CWND, but not for TCP fastopen cookies. Its better to try previous cookie. If it appears to be obsolete, server will send us new cookie anyway. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Yuchung Cheng <ycheng@google.com> Cc: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-11-16tcp: handle tcp_net_metrics_init() order-5 memory allocation failuresEric Dumazet
order-5 allocations can fail with current kernels, we should try vmalloc() as well. Reported-by: Julien Tinnes <jln@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-11-01tcp: Fix double sizeof in new tcp_metrics codeJulian Anastasov
Fix double sizeof when parsing IPv6 address from user space because it breaks get/del by specific IPv6 address. Problem noticed by David Binderman: https://bugzilla.kernel.org/show_bug.cgi?id=49171 Signed-off-by: Julian Anastasov <ja@ssi.bg> 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>
2012-09-05tcp: add generic netlink support for tcp_metricsJulian Anastasov
Add support for genl "tcp_metrics". No locking is changed, only that now we can unlink and delete entries after grace period. We implement get/del for single entry and dump to support show/flush filtering in user space. Del without address attribute causes flush for all addresses, sadly under genl_mutex. v2: - remove rcu_assign_pointer as suggested by Eric Dumazet, it is not needed because there are no other writes under lock - move the flushing code in tcp_metrics_flush_all v3: - remove synchronize_rcu on flush as suggested by Eric Dumazet Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-08-09tcp: must free metrics at net dismantleEric Dumazet
We currently leak all tcp metrics at struct net dismantle time. tcp_net_metrics_exit() frees the hash table, we must first iterate it to free all metrics. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-23tcp: avoid oops in tcp_metrics and reset tcpm_stampJulian Anastasov
In tcp_tw_remember_stamp we incorrectly checked tw instead of tm, it can lead to oops if the cached entry is not found. tcpm_stamp was not updated in tcpm_check_stamp when tcpm_suck_dst was called, move the update into tcpm_suck_dst, so that we do not call it infinitely on every next cache hit after TCP_METRICS_TIMEOUT. Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-20tcp: use hash_32() in tcp_metricsEric Dumazet
Fix a missing roundup_pow_of_two(), since tcpmhash_entries is not guaranteed to be a power of two. Uses hash_32() instead of custom hash. tcpmhash_entries should be an unsigned int. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-19net-tcp: Fast Open client - detecting SYN-data dropsYuchung Cheng
On paths with firewalls dropping SYN with data or experimental TCP options, Fast Open connections will have experience SYN timeout and bad performance. The solution is to track such incidents in the cookie cache and disables Fast Open temporarily. Since only the original SYN includes data and/or Fast Open option, the SYN-ACK has some tell-tale sign (tcp_rcv_fastopen_synack()) to detect such drops. If a path has recurring Fast Open SYN drops, Fast Open is disabled for 2^(recurring_losses) minutes starting from four minutes up to roughly one and half day. sendmsg with MSG_FASTOPEN flag will succeed but it behaves as connect() then write(). Signed-off-by: Yuchung Cheng <ycheng@google.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-19net-tcp: Fast Open client - cookie cacheYuchung Cheng
With help from Eric Dumazet, add Fast Open metrics in tcp metrics cache. The basic ones are MSS and the cookies. Later patch will cache more to handle unfriendly middleboxes. Signed-off-by: Yuchung Cheng <ycheng@google.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-18ipv6: add ipv6_addr_hash() helperEric Dumazet
Introduce ipv6_addr_hash() helper doing a XOR on all bits of an IPv6 address, with an optimized x86_64 version. Use it in flow dissector, as suggested by Andrew McGregor, to reduce hash collision probabilities in fq_codel (and other users of flow dissector) Use it in ip6_tunnel.c and use more bit shuffling, as suggested by David Laight, as existing hash was ignoring most of them. Use it in sunrpc and use more bit shuffling, using hash_32(). Use it in net/ipv6/addrconf.c, using hash_32() as well. As a cleanup, use it in net/ipv4/tcp_metrics.c Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Andrew McGregor <andrewmcgr@gmail.com> Cc: Dave Taht <dave.taht@gmail.com> Cc: Tom Herbert <therbert@google.com> Cc: David Laight <David.Laight@ACULAB.COM> Cc: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-11tcp: Fix out of bounds access to tcpm_valsAlexander Duyck
The recent patch "tcp: Maintain dynamic metrics in local cache." introduced an out of bounds access due to what appears to be a typo. I believe this change should resolve the issue by replacing the access to RTAX_CWND with TCP_METRIC_CWND. Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-10tcp: Move timestamps from inetpeer to metrics cache.David S. Miller
With help from Lin Ming. Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-10tcp: Maintain dynamic metrics in local cache.David S. Miller
Maintain a local hash table of TCP dynamic metrics blobs. Computed TCP metrics are no longer maintained in the route metrics. The table uses RCU and an extremely simple hash so that it has low latency and low overhead. A simple hash is legitimate because we only make metrics blobs for fully established connections. Some tweaking of the default hash table sizes, metric timeouts, and the hash chain length limit certainly could use some tweaking. But the basic design seems sound. With help from Eric Dumazet and Joe Perches. Signed-off-by: David S. Miller <davem@davemloft.net>