summaryrefslogtreecommitdiff
path: root/net
AgeCommit message (Collapse)Author
2012-07-20ipv4: Remove rt_key_{src,dst,tos} from struct rtable.David Miller
They are always used in contexts where they can be reconstituted, or where the finally resolved rt->rt_{src,dst} is semantically equivalent. Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-20ipv4: Kill ip_route_input_noref().David Miller
The "noref" argument to ip_route_input_common() is now always ignored because we do not cache routes, and in that case we must always grab a reference to the resulting 'dst'. Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-20ipv4: Delete routing cache.David S. Miller
The ipv4 routing cache is non-deterministic, performance wise, and is subject to reasonably easy to launch denial of service attacks. The routing cache works great for well behaved traffic, and the world was a much friendlier place when the tradeoffs that led to the routing cache's design were considered. What it boils down to is that the performance of the routing cache is a product of the traffic patterns seen by a system rather than being a product of the contents of the routing tables. The former of which is controllable by external entitites. Even for "well behaved" legitimate traffic, high volume sites can see hit rates in the routing cache of only ~%10. Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-20tun: fix a crash bug and a memory leakMikulas Patocka
This patch fixes a crash tun_chr_close -> netdev_run_todo -> tun_free_netdev -> sk_release_kernel -> sock_release -> iput(SOCK_INODE(sock)) introduced by commit 1ab5ecb90cb6a3df1476e052f76a6e8f6511cb3d The problem is that this socket is embedded in struct tun_struct, it has no inode, iput is called on invalid inode, which modifies invalid memory and optionally causes a crash. sock_release also decrements sockets_in_use, this causes a bug that "sockets: used" field in /proc/*/net/sockstat keeps on decreasing when creating and closing tun devices. This patch introduces a flag SOCK_EXTERNALLY_ALLOCATED that instructs sock_release to not free the inode and not decrement sockets_in_use, fixing both memory corruption and sockets_in_use underflow. It should be backported to 3.3 an 3.4 stabke. Signed-off-by: Mikulas Patocka <mikulas@artax.karlin.mff.cuni.cz> Cc: stable@kernel.org Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-20ipv4: show pmtu in route listJulian Anastasov
Override the metrics with rt_pmtu Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-20rtnl: allow to specify number of rx and tx queues on device creationJiri Pirko
This patch introduces IFLA_NUM_TX_QUEUES and IFLA_NUM_RX_QUEUES by which userspace can set number of rx and/or tx queues to be allocated for newly created netdevice. This overrides ops->get_num_[tr]x_queues() Signed-off-by: Jiri Pirko <jiri@resnulli.us> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-20rtnl: allow to specify different num for rx and tx queue countJiri Pirko
Also cut out unused function parameters and possible err in return value. Signed-off-by: Jiri Pirko <jiri@resnulli.us> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-20tcp: improve latencies of timer triggered eventsEric Dumazet
Modern TCP stack highly depends on tcp_write_timer() having a small latency, but current implementation doesn't exactly meet the expectations. When a timer fires but finds the socket is owned by the user, it rearms itself for an additional delay hoping next run will be more successful. tcp_write_timer() for example uses a 50ms delay for next try, and it defeats many attempts to get predictable TCP behavior in term of latencies. Use the recently introduced tcp_release_cb(), so that the user owning the socket will call various handlers right before socket release. This will permit us to post a followup patch to address the tcp_tso_should_defer() syndrome (some deferred packets have to wait RTO timer to be transmitted, while cwnd should allow us to send them sooner) Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Tom Herbert <therbert@google.com> Cc: Yuchung Cheng <ycheng@google.com> Cc: Neal Cardwell <ncardwell@google.com> Cc: Nandita Dukkipati <nanditad@google.com> Cc: H.K. Jerry Chu <hkchu@google.com> Cc: John Heffner <johnwheffner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-20tcp: fix ABC in tcp_slow_start()Eric Dumazet
When/if sysctl_tcp_abc > 1, we expect to increase cwnd by 2 if the received ACK acknowledges more than 2*MSS bytes, in tcp_slow_start() Problem is this RFC 3465 statement is not correctly coded, as the while () loop increases snd_cwnd one by one. Add a new variable to avoid this off-by one error. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Tom Herbert <therbert@google.com> Cc: Yuchung Cheng <ycheng@google.com> Cc: Neal Cardwell <ncardwell@google.com> Cc: Nandita Dukkipati <nanditad@google.com> Cc: John Heffner <johnwheffner@gmail.com> Cc: Stephen Hemminger <shemminger@vyatta.com> Acked-by: Yuchung Cheng <ycheng@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> 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>
2012-07-20tcp: Return bool instead of int where appropriateVijay Subramanian
Applied to a set of static inline functions in tcp_input.c Signed-off-by: Vijay Subramanian <subramanian.vijay@gmail.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-20Merge branch 'master' of ↵John W. Linville
git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-next into for-davem
2012-07-19Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client Pull last minute Ceph fixes from Sage Weil: "The important one fixes a bug in the socket failure handling behavior that was turned up in some recent failure injection testing. The other two are minor bug fixes." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: rbd: endian bug in rbd_req_cb() rbd: Fix ceph_snap_context size calculation libceph: fix messenger retry
2012-07-19ipv4: Fix again the time difference calculationJulian Anastasov
Fix again the diff value in rt_bind_exception after collision of two latest patches, my original commit actually fixed the same problem. Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-19Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Conflicts: drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c
2012-07-19net-tcp: Fast Open client - cookie-less modeYuchung Cheng
In trusted networks, e.g., intranet, data-center, the client does not need to use Fast Open cookie to mitigate DoS attacks. In cookie-less mode, sendmsg() with MSG_FASTOPEN flag will send SYN-data regardless of cookie availability. 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 - 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 - sendmsg(MSG_FASTOPEN)Yuchung Cheng
sendmsg() (or sendto()) with MSG_FASTOPEN is a combo of connect(2) and write(2). The application should replace connect() with it to send data in the opening SYN packet. For blocking socket, sendmsg() blocks until all the data are buffered locally and the handshake is completed like connect() call. It returns similar errno like connect() if the TCP handshake fails. For non-blocking socket, it returns the number of bytes queued (and transmitted in the SYN-data packet) if cookie is available. If cookie is not available, it transmits a data-less SYN packet with Fast Open cookie request option and returns -EINPROGRESS like connect(). Using MSG_FASTOPEN on connecting or connected socket will result in simlar errno like repeating connect() calls. Therefore the application should only use this flag on new sockets. The buffer size of sendmsg() is independent of the MSS of the connection. 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 - receiving SYN-ACKYuchung Cheng
On receiving the SYN-ACK after SYN-data, the client needs to a) update the cached MSS and cookie (if included in SYN-ACK) b) retransmit the data not yet acknowledged by the SYN-ACK in the final ACK of the handshake. 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 - sending SYN-dataYuchung Cheng
This patch implements sending SYN-data in tcp_connect(). The data is from tcp_sendmsg() with flag MSG_FASTOPEN (implemented in a later patch). The length of the cookie in tcp_fastopen_req, init'd to 0, controls the type of the SYN. If the cookie is not cached (len==0), the host sends data-less SYN with Fast Open cookie request option to solicit a cookie from the remote. If cookie is not available (len > 0), the host sends a SYN-data with Fast Open cookie option. If cookie length is negative, the SYN will not include any Fast Open option (for fall back operations). To deal with middleboxes that may drop SYN with data or experimental TCP option, the SYN-data is only sent once. SYN retransmits do not include data or Fast Open options. The connection will fall back to regular TCP handshake. 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>
2012-07-19net-tcp: Fast Open baseYuchung Cheng
This patch impelements the common code for both the client and server. 1. TCP Fast Open option processing. Since Fast Open does not have an option number assigned by IANA yet, it shares the experiment option code 254 by implementing draft-ietf-tcpm-experimental-options with a 16 bits magic number 0xF989. This enables global experiments without clashing the scarce(2) experimental options available for TCP. When the draft status becomes standard (maybe), the client should switch to the new option number assigned while the server supports both numbers for transistion. 2. The new sysctl tcp_fastopen 3. A place holder init function Signed-off-by: Yuchung Cheng <ycheng@google.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-19ipx: move peII functionsstephen hemminger
The Ethernet II wrapper is only used by IPX protocol, may have once been used by Appletalk but not currently. Therefore it makes sense to move it to the IPX dust bin and drop the exports. Build tested only. Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-19ipv4: tcp: remove per net tcp_sockEric Dumazet
tcp_v4_send_reset() and tcp_v4_send_ack() use a single socket per network namespace. This leads to bad behavior on multiqueue NICS, because many cpus contend for the socket lock and once socket lock is acquired, extra false sharing on various socket fields slow down the operations. To better resist to attacks, we use a percpu socket. Each cpu can run without contention, using appropriate memory (local node) Additional features : 1) We also mirror the queue_mapping of the incoming skb, so that answers use the same queue if possible. 2) Setting SOCK_USE_WRITE_QUEUE socket flag speedup sock_wfree() 3) We now limit the number of in-flight RST/ACK [1] packets per cpu, instead of per namespace, and we honor the sysctl_wmem_default limit dynamically. (Prior to this patch, sysctl_wmem_default value was copied at boot time, so any further change would not affect tcp_sock limit) [1] These packets are only generated when no socket was matched for the incoming packet. Reported-by: Bill Sommerfeld <wsommerfeld@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Tom Herbert <therbert@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-19ipv4: use seqlock for nh_exceptionsJulian Anastasov
Use global seqlock for the nh_exceptions. Call fnhe_oldest with the right hash chain. Correct the diff value for dst_set_expires. v2: after suggestions from Eric Dumazet: * get rid of spin lock fnhe_lock, rearrange update_or_create_fnhe * continue daddr search in rt_bind_exception v3: * remove the daddr check before seqlock in rt_bind_exception * restart lookup in rt_bind_exception on detected seqlock change, as suggested by David Miller Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-19Merge branch 'for-john' of ↵John W. Linville
git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211-next
2012-07-19ipv4: Fix time difference calculation in rt_bind_exception().David S. Miller
Reported-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-19ipv4: fix address selection in fib_compute_spec_dstJulian Anastasov
ip_options_compile can be called for forwarded packets, make sure the specific-destionation address is a local one as specified in RFC 1812, 4.2.2.2 Addresses in Options Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-19ipv4: optimize fib_compute_spec_dst call in ip_options_echoJulian Anastasov
Move fib_compute_spec_dst at the only place where it is needed. Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-18net: Statically initialize init_net.dev_base_headRustad, Mark D
This change eliminates an initialization-order hazard most recently seen when netprio_cgroup is built into the kernel. With thanks to Eric Dumazet for catching a bug. Signed-off-by: Mark Rustad <mark.d.rustad@intel.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-18Merge branch 'master' of ↵John W. Linville
git://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth-next
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>
2012-07-18skbuff: Use correct allocation in skb_copy_ubufsKrishna Kumar
Use correct allocation flags during copy of user space fragments to the kernel. Also "improve" couple of for loops. Signed-off-by: Krishna Kumar <krkumar2@in.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-18net/ipv4: VTI support new module for ip_vti.Saurabh
New VTI tunnel kernel module, Kconfig and Makefile changes. Signed-off-by: Saurabh Mohan <saurabh.mohan@vyatta.com> Reviewed-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-18net/ipv4: VTI support rx-path hook in xfrm4_mode_tunnel.Saurabh
Incorporated David and Steffen's comments. Add hook for rx-path xfmr4_mode_tunnel for VTI tunnel module. Signed-off-by: Saurabh Mohan <saurabh.mohan@vyatta.com> Reviewed-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-18tcp: refine SYN handling in tcp_validate_incomingEric Dumazet
Followup of commit 0c24604b68fc (tcp: implement RFC 5961 4.2) As reported by Vijay Subramanian, we should send a challenge ACK instead of a dup ack if a SYN flag is set on a packet received out of window. This permits the ratelimiting to work as intended, and to increase correct SNMP counters. Suggested-by: Vijay Subramanian <subramanian.vijay@gmail.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Vijay Subramanian <subramanian.vijay@gmail.com> Cc: Kiran Kumar Kella <kkiran@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-18cipso: don't follow a NULL pointer when setsockopt() is calledPaul Moore
As reported by Alan Cox, and verified by Lin Ming, when a user attempts to add a CIPSO option to a socket using the CIPSO_V4_TAG_LOCAL tag the kernel dies a terrible death when it attempts to follow a NULL pointer (the skb argument to cipso_v4_validate() is NULL when called via the setsockopt() syscall). This patch fixes this by first checking to ensure that the skb is non-NULL before using it to find the incoming network interface. In the unlikely case where the skb is NULL and the user attempts to add a CIPSO option with the _TAG_LOCAL tag we return an error as this is not something we want to allow. A simple reproducer, kindly supplied by Lin Ming, although you must have the CIPSO DOI #3 configure on the system first or you will be caught early in cipso_v4_validate(): #include <sys/types.h> #include <sys/socket.h> #include <linux/ip.h> #include <linux/in.h> #include <string.h> struct local_tag { char type; char length; char info[4]; }; struct cipso { char type; char length; char doi[4]; struct local_tag local; }; int main(int argc, char **argv) { int sockfd; struct cipso cipso = { .type = IPOPT_CIPSO, .length = sizeof(struct cipso), .local = { .type = 128, .length = sizeof(struct local_tag), }, }; memset(cipso.doi, 0, 4); cipso.doi[3] = 3; sockfd = socket(AF_INET, SOCK_DGRAM, 0); #define SOL_IP 0 setsockopt(sockfd, SOL_IP, IP_OPTIONS, &cipso, sizeof(struct cipso)); return 0; } CC: Lin Ming <mlin@ss.pku.edu.cn> Reported-by: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Paul Moore <pmoore@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-18ipv6: fix inet6_csk_xmit()Eric Dumazet
We should provide to inet6_csk_route_socket a struct flowi6 pointer, so that net6_csk_xmit() works correctly instead of sending garbage. Also add some consts Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Yuchung Cheng <ycheng@google.com> Cc: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-18mac80211: flush stations before stop beaconingEliad Peller
When AP interface is going down, the stations are flushed (in ieee80211_do_stop()) only after the beaconing was stopped. However, drivers might rely on stations being removed before the beaconing was stopped, in order to clean up properly. Fix it by flushing the stations on ap stop. (we already do the same for other interface types, e.g. in ieee80211_set_disassoc()) Signed-off-by: Eliad Peller <eliad@wizery.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2012-07-18cfg80211: Fix mutex locking in reg_last_request_cell_baseMohammed Shafi Shajakhan
should fix the following issue [ 3229.815012] [ BUG: lock held when returning to user space! ] [ 3229.815016] 3.5.0-rc7-wl #28 Tainted: G W O [ 3229.815017] ------------------------------------------------ [ 3229.815019] wpa_supplicant/5783 is leaving the kernel with locks still held! [ 3229.815022] 1 lock held by wpa_supplicant/5783: [ 3229.815023] #0: (reg_mutex){+.+.+.}, at: [<fa65834d>] reg_last_request_cell_base+0x1d/0x60 [cfg80211] Cc: Luis Rodriguez <mcgrof@gmail.com> Signed-off-by: Mohammed Shafi Shajakhan <mohammed@qca.qualcomm.com> Tested-by: Luciano Coelho <coelho@ti.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2012-07-18libceph: fix messenger retrySage Weil
In ancient times, the messenger could both initiate and accept connections. An artifact if that was data structures to store/process an incoming ceph_msg_connect request and send an outgoing ceph_msg_connect_reply. Sadly, the negotiation code was referencing those structures and ignoring important information (like the peer's connect_seq) from the correct ones. Among other things, this fixes tight reconnect loops where the server sends RETRY_SESSION and we (the client) retries with the same connect_seq as last time. This bug pretty easily triggered by injecting socket failures on the MDS and running some fs workload like workunits/direct_io/test_sync_io. Signed-off-by: Sage Weil <sage@inktank.com>
2012-07-17SUNRPC: Add a missing spin_unlock to gss_mech_list_pseudoflavorsTrond Myklebust
The patch "SUNRPC: Add rpcauth_list_flavors()" introduces a new error path in gss_mech_list_pseudoflavors, but fails to release the spin lock. Reported-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
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: Fix nexthop exception hash computation.David S. Miller
Need to mask it with (FNHE_HASH_SIZE - 1). Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-17Merge branch 'master' of ↵John W. Linville
git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless
2012-07-17Merge branch 'for-john' of ↵John W. Linville
git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211-next
2012-07-17Merge branch 'nexthop_exceptions'David S. Miller
These patches implement the final mechanism necessary to really allow us to go without the route cache in ipv4. We need a place to have long-term storage of PMTU/redirect information which is independent of the routes themselves, yet does not get us back into a situation where we have to write to metrics or anything like that. For this we use an "next-hop exception" table in the FIB nexthops. The one thing I desperately want to avoid is having to create clone routes in the FIB trie for this purpose, because that is very expensive. However, I'm willing to entertain such an idea later if this current scheme proves to have downsides that the FIB trie variant would not have. In order to accomodate this any such scheme, we need to be able to produce a full flow key at PMTU/redirect time. That required an adjustment of the interface call-sites used to propagate these events. For a PMTU/redirect with a fully specified socket, we pass that socket and use it to produce the flow key. Otherwise we use a passed in SKB to formulate the key. There are two cases that need to be distinguished, ICMP message processing (in which case the IP header is at skb->data) and output packet processing (mostly tunnels, and in all such cases the IP header is at ip_hdr(skb)). We also have to make the code able to handle the case where the dst itself passed into the dst_ops->{update_pmtu,redirect} method is invalidated. This matters for calls from sockets that have cached that route. We provide a inet{,6} helper function for this purpose, and edit SCTP specially since it caches routes at the transport rather than socket level. Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-17netpoll: move np->dev and np->dev_name init into __netpoll_setup()Jiri Pirko
Signed-off-by: Jiri Pirko <jiri@resnulli.us> 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>
2012-07-17tcp: implement RFC 5961 4.2Eric Dumazet
Implement the RFC 5691 mitigation against Blind Reset attack using SYN bit. Section 4.2 of RFC 5961 advises to send a Challenge ACK and drop incoming packet, instead of resetting the session. Add a new SNMP counter to count number of challenge acks sent in response to SYN packets. (netstat -s | grep TCPSYNChallenge) Remove obsolete TCPAbortOnSyn, since we no longer abort a TCP session because of a SYN flag. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Kiran Kumar Kella <kkiran@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>