- 29 9月, 2014 1 次提交
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由 Eric Dumazet 提交于
ipv6_opt_accepted() assumes IP6CB(skb) holds the struct inet6_skb_parm that it needs. Lets not assume this, as TCP stack might use a different place. Signed-off-by: NEric Dumazet <edumazet@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 05 9月, 2014 1 次提交
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由 Hannes Frederic Sowa 提交于
This patch adds a new sysctl_mld_qrv knob to configure the mldv1/v2 query robustness variable. It specifies how many retransmit of unsolicited mld retransmit should happen. Admins might want to tune this on lossy links. Also reset mld state on interface down/up, so we pick up new sysctl settings during interface up event. IPv6 certification requests this knob to be available. I didn't make this knob netns specific, as it is mostly a setting in a physical environment and should be per host. Cc: Flavio Leitner <fbl@redhat.com> Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org> Acked-by: NFlavio Leitner <fbl@redhat.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 28 7月, 2014 2 次提交
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由 Florian Westphal 提交于
The 'nqueues' counter is protected by the lru list lock, once thats removed this needs to be converted to atomic counter. Given this isn't used for anything except for reporting it to userspace via /proc, just remove it. We still report the memory currently used by fragment reassembly queues. Signed-off-by: NFlorian Westphal <fw@strlen.de> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Florian Westphal 提交于
Signed-off-by: NFlorian Westphal <fw@strlen.de> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 17 7月, 2014 1 次提交
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由 Jeff Layton 提交于
sparse is throwing warnings when building sunrpc modules due to some endianness shenanigans in ipv6.h. Specifically: CHECK net/sunrpc/addr.c include/net/ipv6.h:573:17: warning: restricted __be64 degrades to integer include/net/ipv6.h:577:34: warning: restricted __be32 degrades to integer include/net/ipv6.h:573:17: warning: restricted __be64 degrades to integer include/net/ipv6.h:577:34: warning: restricted __be32 degrades to integer Sprinkle some endianness fixups to silence them. These should all get fixed up at compile time, so I don't think this will add any extra work to be done at runtime. Signed-off-by: NJeff Layton <jlayton@primarydata.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 09 7月, 2014 1 次提交
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由 Florian Fainelli 提交于
Commit cb1ce2ef ("ipv6: Implement automatic flow label generation on transmit") introduced ip6_make_flowlabel, while commit b73c3d0e ("net: Save TX flow hash in sock and set in skbuf on xmit") introduced ip6_set_txhash. ip6_set_tx_hash() uses sk_v6_daddr which references __sk_common.skc_v6_daddr from struct sock_common, which is gated with IS_ENABLED(CONFIG_IPV6). ip6_make_flowlabel() uses the ipv6 member from struct net which is also gated with IS_ENABLED(CONFIG_IPV6). When CONFIG_IPV6 is disabled, we will hit a build failure that looks like this when the compiler attempts inlining these functions: CC [M] drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.o In file included from include/net/inet_sock.h:27:0, from include/net/ip.h:30, from drivers/net/ethernet/broadcom/cnic.c:37: include/net/ipv6.h: In function 'ip6_set_txhash': include/net/sock.h:327:33: error: 'struct sock_common' has no member named 'skc_v6_daddr' #define sk_v6_daddr __sk_common.skc_v6_daddr ^ include/net/ipv6.h:696:49: note: in expansion of macro 'sk_v6_daddr' keys.dst = (__force __be32)ipv6_addr_hash(&sk->sk_v6_daddr); ^ In file included from include/net/inetpeer.h:15:0, from include/net/route.h:28, from include/net/ip.h:31, from drivers/net/ethernet/broadcom/cnic.c:37: include/net/ipv6.h: In function 'ip6_make_flowlabel': include/net/ipv6.h:706:37: error: 'struct net' has no member named 'ipv6' if (!flowlabel && (autolabel || net->ipv6.sysctl.auto_flowlabels)) { ^ Fixes: cb1ce2ef ("ipv6: Implement automatic flow label generation on transmit") Fixes: b73c3d0e ("net: Save TX flow hash in sock and set in skbuf on xmit") Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 08 7月, 2014 2 次提交
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由 Tom Herbert 提交于
Automatically generate flow labels for IPv6 packets on transmit. The flow label is computed based on skb_get_hash. The flow label will only automatically be set when it is zero otherwise (i.e. flow label manager hasn't set one). This supports the transmit side functionality of RFC 6438. Added an IPv6 sysctl auto_flowlabels to enable/disable this behavior system wide, and added IPV6_AUTOFLOWLABEL socket option to enable this functionality per socket. By default, auto flowlabels are disabled to avoid possible conflicts with flow label manager, however if this feature proves useful we may want to enable it by default. It should also be noted that FreeBSD has already implemented automatic flow labels (including the sysctl and socket option). In FreeBSD, automatic flow labels default to enabled. Performance impact: Running super_netperf with 200 flows for TCP_RR and UDP_RR for IPv6. Note that in UDP case, __skb_get_hash will be called for every packet with explains slight regression. In the TCP case the hash is saved in the socket so there is no regression. Automatic flow labels disabled: TCP_RR: 86.53% CPU utilization 127/195/322 90/95/99% latencies 1.40498e+06 tps UDP_RR: 90.70% CPU utilization 118/168/243 90/95/99% latencies 1.50309e+06 tps Automatic flow labels enabled: TCP_RR: 85.90% CPU utilization 128/199/337 90/95/99% latencies 1.40051e+06 UDP_RR 92.61% CPU utilization 115/164/236 90/95/99% latencies 1.4687e+06 Signed-off-by: NTom Herbert <therbert@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Tom Herbert 提交于
For a connected socket we can precompute the flow hash for setting in skb->hash on output. This is a performance advantage over calculating the skb->hash for every packet on the connection. The computation is done using the common hash algorithm to be consistent with computations done for packets of the connection in other states where thers is no socket (e.g. time-wait, syn-recv, syn-cookies). This patch adds sk_txhash to the sock structure. inet_set_txhash and ip6_set_txhash functions are added which are called from points in TCP and UDP where socket moves to established state. skb_set_hash_from_sk is a function which sets skb->hash from the sock txhash value. This is called in UDP and TCP transmit path when transmitting within the context of a socket. Tested: ran super_netperf with 200 TCP_RR streams over a vxlan interface (in this case skb_get_hash called on every TX packet to create a UDP source port). Before fix: 95.02% CPU utilization 154/256/505 90/95/99% latencies 1.13042e+06 tps Time in functions: 0.28% skb_flow_dissect 0.21% __skb_get_hash After fix: 94.95% CPU utilization 156/254/485 90/95/99% latencies 1.15447e+06 Neither __skb_get_hash nor skb_flow_dissect appear in perf Signed-off-by: NTom Herbert <therbert@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 03 6月, 2014 1 次提交
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由 Eric Dumazet 提交于
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: NEric Dumazet <edumazet@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 14 5月, 2014 1 次提交
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由 Lorenzo Colitti 提交于
Kernel-originated IP packets that have no user socket associated with them (e.g., ICMP errors and echo replies, TCP RSTs, etc.) are emitted with a mark of zero. Add a sysctl to make them have the same mark as the packet they are replying to. This allows an administrator that wishes to do so to use mark-based routing, firewalling, etc. for these replies by marking the original packets inbound. Tested using user-mode linux: - ICMP/ICMPv6 echo replies and errors. - TCP RST packets (IPv4 and IPv6). Signed-off-by: NLorenzo Colitti <lorenzo@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 01 5月, 2014 1 次提交
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由 Lorenzo Colitti 提交于
This replaces 6 identical code snippets with a call to a new static inline function. Signed-off-by: NLorenzo Colitti <lorenzo@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 16 4月, 2014 1 次提交
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由 Eric Dumazet 提交于
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: 8f646c92 ("vxlan: keep original skb ownership") Reported-by: Nlucien xin <lucien.xin@gmail.com> Signed-off-by: NEric Dumazet <edumazet@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 22 1月, 2014 1 次提交
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由 Hannes Frederic Sowa 提交于
Some ipv6 protocols cannot handle ipv4 addresses, so we must not allow connecting and binding to them. sendmsg logic does already check msg->name for this but must trust already connected sockets which could be set up for connection to ipv4 address family. Per-socket flag ipv6only is of no use here, as it is under users control by setsockopt. Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 20 1月, 2014 1 次提交
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由 Florent Fourcot 提交于
This information is already available via IPV6_FLOWINFO of IPV6_2292PKTOPTIONS, and them a filtering to get the flow label information. But it is probably logical and easier for users to add this here, and to control both sent/received flow label values with the IPV6_FLOWLABEL_MGR option. Signed-off-by: NFlorent Fourcot <florent.fourcot@enst-bretagne.fr> Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 16 1月, 2014 1 次提交
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由 Li RongQing 提交于
Two places defined IPV6_TCLASS_SHIFT, so we should move it into ipv6.h, and use this macro as possible. And define ip6_tclass helper to return tclass Signed-off-by: NLi RongQing <roy.qing.li@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 02 1月, 2014 1 次提交
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由 stephen hemminger 提交于
Running 'make namespacecheck' shows: net/ipv6/route.o ipv6_route_table_template rt6_bind_peer net/ipv6/icmp.o icmpv6_route_lookup ipv6_icmp_table_template This addresses some of those warnings by: * make icmpv6_route_lookup static * move inline's out of ip6_route.h since only used into route.c * move rt6_bind_peer into route.c Signed-off-by: NStephen Hemminger <stephen@networkplumber.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 10 12月, 2013 2 次提交
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由 Florent Fourcot 提交于
And use it if possible. Signed-off-by: NFlorent Fourcot <florent.fourcot@enst-bretagne.fr> Reviewed-by: NHannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Florent Fourcot 提交于
Signed-off-by: NFlorent Fourcot <florent.fourcot@enst-bretagne.fr> Reviewed-by: NHannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 06 12月, 2013 2 次提交
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由 Steffen Klassert 提交于
FLOWI_FLAG_CAN_SLEEP was used to notify xfrm about the posibility to sleep until the needed states are resolved. This code is gone, so FLOWI_FLAG_CAN_SLEEP is not needed anymore. Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>
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由 Paul Durrant 提交于
The code to detect fragments in checksum_setup() was missing for IPv4 and too eager for IPv6. (It transpires that Windows seems to send IPv6 packets with a fragment header even if they are not a fragment - i.e. offset is zero, and M bit is not set). This patch also incorporates a fix to callers of maybe_pull_tail() where skb->network_header was being erroneously added to the length argument. Signed-off-by: NPaul Durrant <paul.durrant@citrix.com> Signed-off-by: NZoltan Kiss <zoltan.kiss@citrix.com> Cc: Wei Liu <wei.liu2@citrix.com> Cc: Ian Campbell <ian.campbell@citrix.com> Cc: David Vrabel <david.vrabel@citrix.com> cc: David Miller <davem@davemloft.net> Acked-by: NWei Liu <wei.liu2@citrix.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 24 11月, 2013 1 次提交
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由 Hannes Frederic Sowa 提交于
Commit bceaa902 ("inet: prevent leakage of uninitialized memory to user in recv syscalls") conditionally updated addr_len if the msg_name is written to. The recv_error and rxpmtu functions relied on the recvmsg functions to set up addr_len before. As this does not happen any more we have to pass addr_len to those functions as well and set it to the size of the corresponding sockaddr length. This broke traceroute and such. Fixes: bceaa902 ("inet: prevent leakage of uninitialized memory to user in recv syscalls") Reported-by: NBrad Spengler <spender@grsecurity.net> Reported-by: Tom Labanowski Cc: mpb <mpb.mail@gmail.com> Cc: David S. Miller <davem@davemloft.net> Cc: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 09 11月, 2013 1 次提交
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由 Florent Fourcot 提交于
It is already possible to set/put/renew a label with IPV6_FLOWLABEL_MGR and setsockopt. This patch add the possibility to get information about this label (current value, time before expiration, etc). It helps application to take decision for a renew or a release of the label. v2: * Add spin_lock to prevent race condition * return -ENOENT if no result found * check if flr_action is GET v3: * move the spin_lock to protect only the relevant code Signed-off-by: NFlorent Fourcot <florent.fourcot@enst-bretagne.fr> Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 24 10月, 2013 1 次提交
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由 Hannes Frederic Sowa 提交于
Defer the fragmentation hash secret initialization for IPv6 like the previous patch did for IPv4. Because the netfilter logic reuses the hash secret we have to split it first. Thus introduce a new nf_hash_frag function which takes care to seed the hash secret. Cc: David S. Miller <davem@davemloft.net> Cc: Eric Dumazet <edumazet@google.com> Cc: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 20 10月, 2013 1 次提交
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由 Hannes Frederic Sowa 提交于
This patch splits the inet6_ehashfn into separate ones in ipv6/inet6_hashtables.o and ipv6/udp.o to ease the introduction of seperate secrets keys later. Cc: Eric Dumazet <edumazet@google.com> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 22 9月, 2013 1 次提交
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由 Joe Perches 提交于
There are a mix of function prototypes with and without extern in the kernel sources. Standardize on not using extern for function prototypes. Function prototypes don't need to be written with extern. extern is assumed by the compiler. Its use is as unnecessary as using auto to declare automatic/local variables in a block. Signed-off-by: NJoe Perches <joe@perches.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 01 9月, 2013 1 次提交
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由 Cong Wang 提交于
It will be used by vxlan, and may not be inlined. Cc: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: NCong Wang <amwang@redhat.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 24 8月, 2013 1 次提交
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由 Joe Stringer 提交于
Signed-off-by: NJoe Stringer <joe@wand.net.nz> Signed-off-by: NJesse Gross <jesse@nicira.com>
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- 20 6月, 2013 1 次提交
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由 Joe Perches 提交于
This typedef is unnecessary and should just be removed. Signed-off-by: NJoe Perches <joe@perches.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 26 5月, 2013 1 次提交
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由 Lorenzo Colitti 提交于
This adds the ability to send ICMPv6 echo requests without a raw socket. The equivalent ability for ICMPv4 was added in 2011. Instead of having separate code paths for IPv4 and IPv6, make most of the code in net/ipv4/ping.c dual-stack and only add a few IPv6-specific bits (like the protocol definition) to a new net/ipv6/ping.c. Hopefully this will reduce divergence and/or duplication of bugs in the future. Caveats: - Setting options via ancillary data (e.g., using IPV6_PKTINFO to specify the outgoing interface) is not yet supported. - There are no separate security settings for IPv4 and IPv6; everything is controlled by /proc/net/ipv4/ping_group_range. - The proc interface does not yet display IPv6 ping sockets properly. Tested with a patched copy of ping6 and using raw socket calls. Compiles and works with all of CONFIG_IPV6={n,m,y}. Signed-off-by: NLorenzo Colitti <lorenzo@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 25 3月, 2013 1 次提交
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由 Hannes Frederic Sowa 提交于
Hello! After patch 1 got accepted to net-next I will also send a patch to netfilter-devel to make the corresponding changes to the netfilter reassembly logic. Thanks, Hannes -- >8 -- [PATCH 2/2] ipv6: implement RFC3168 5.3 (ecn protection) for ipv6 fragmentation handling This patch also ensures that INET_ECN_CE is propagated if one fragment had the codepoint set. Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Jesper Dangaard Brouer <jbrouer@redhat.com> Cc: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org> Acked-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 09 3月, 2013 1 次提交
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由 Hannes Frederic Sowa 提交于
__ipv6_addr_needs_scope_id checks if an ipv6 address needs to supply a 'sin6_scope_id != 0'. 'sin6_scope_id != 0' was enforced in case of link-local addresses. To support interface-local multicast these checks had to be enhanced and are now consolidated into these new helper functions. v2: a) migrated to struct ipv6_addr_props v3: a) reverted changes for ipv6_addr_props b) test for address type instead of comparing scope v4: a) unchanged Suggested-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Cc: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Acked-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org> Acked-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 08 3月, 2013 1 次提交
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由 Eric Dumazet 提交于
Commit 18367681 (ipv6 flowlabel: Convert np->ipv6_fl_list to RCU.) omitted proper __rcu annotations. Signed-off-by: NEric Dumazet <edumazet@google.com> Cc: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 22 2月, 2013 1 次提交
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由 Eric Dumazet 提交于
It looks like its possible to open thousands of TCP IPv6 sessions on a server, all landing in a single slot of TCP hash table. Incoming packets have to lookup sockets in a very long list. We should hash all bits from foreign IPv6 addresses, using a salt and hash mix, not a simple XOR. inet6_ehashfn() can also separately use the ports, instead of xoring them. Reported-by: NNeal Cardwell <ncardwell@google.com> Signed-off-by: NEric Dumazet <edumazet@google.com> Cc: Yuchung Cheng <ycheng@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 31 1月, 2013 2 次提交
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由 YOSHIFUJI Hideaki / 吉藤英明 提交于
Signed-off-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 YOSHIFUJI Hideaki / 吉藤英明 提交于
Signed-off-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 30 1月, 2013 1 次提交
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由 Jesper Dangaard Brouer 提交于
This change is primarily a preparation to ease the extension of memory limit tracking. The change does reduce the number atomic operation, during freeing of a frag queue. This does introduce a some performance improvement, as these atomic operations are at the core of the performance problems seen on NUMA systems. Signed-off-by: NJesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 22 1月, 2013 1 次提交
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由 YOSHIFUJI Hideaki / 吉藤英明 提交于
- move ip6_nd_hdr() to its users' source files. In net/ipv6/mcast.c, it will be called ip6_mc_hdr(). - make return type to void since this function never fails. Signed-off-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 18 1月, 2013 2 次提交
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由 Fabio Baltieri 提交于
Fix the 64bit optimized version of ipv6_prefix_equal to convert the bitmask to network byte order only after the bit-shift. The bug was introduced in: 38675170 ipv6: 64bit version of ipv6_prefix_equal(). Signed-off-by: NFabio Baltieri <fabio.baltieri@linaro.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Jesper Dangaard Brouer 提交于
Increase the amount of memory usage limits for incomplete IP fragments. Arguing for new thresh high/low values: High threshold = 4 MBytes Low threshold = 3 MBytes The fragmentation memory accounting code, tries to account for the real memory usage, by measuring both the size of frag queue struct (inet_frag_queue (ipv4:ipq/ipv6:frag_queue)) and the SKB's truesize. We want to be able to handle/hold-on-to enough fragments, to ensure good performance, without causing incomplete fragments to hurt scalability, by causing the number of inet_frag_queue to grow too much (resulting longer searches for frag queues). For IPv4, how much memory does the largest frag consume. Maximum size fragment is 64K, which is approx 44 fragments with MTU(1500) sized packets. Sizeof(struct ipq) is 200. A 1500 byte packet results in a truesize of 2944 (not 2048 as I first assumed) (44*2944)+200 = 129736 bytes The current default high thresh of 262144 bytes, is obviously problematic, as only two 64K fragments can fit in the queue at the same time. How many 64K fragment can we fit into 4 MBytes: 4*2^20/((44*2944)+200) = 32.34 fragment in queues An attacker could send a separate/distinct fake fragment packets per queue, causing us to allocate one inet_frag_queue per packet, and thus attacking the hash table and its lists. How many frag queue do we need to store, and given a current hash size of 64, what is the average list length. Using one MTU sized fragment per inet_frag_queue, each consuming (2944+200) 3144 bytes. 4*2^20/(2944+200) = 1334 frag queues -> 21 avg list length An attack could send small fragments, the smallest packet I could send resulted in a truesize of 896 bytes (I'm a little surprised by this). 4*2^20/(896+200) = 3827 frag queues -> 59 avg list length When increasing these number, we also need to followup with improvements, that is going to help scalability. Simply increasing the hash size, is not enough as the current implementation does not have a per hash bucket locking. Signed-off-by: NJesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 17 1月, 2013 1 次提交
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由 YOSHIFUJI Hideaki 提交于
Commit 3e4e4c1f ("ipv6: Introduce ip6_flow_hdr() to fill version, tclass and flowlabel.) uses ntohl(), which should be htonl(). Found by Fengguang Wu <fengguang.wu@intel.com>. Signed-off-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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