- 06 11月, 2013 1 次提交
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由 Hannes Frederic Sowa 提交于
Sockets marked with IP_PMTUDISC_INTERFACE won't do path mtu discovery, their sockets won't accept and install new path mtu information and they will always use the interface mtu for outgoing packets. It is guaranteed that the packet is not fragmented locally. But we won't set the DF-Flag on the outgoing frames. Florian Weimer had the idea to use this flag to ensure DNS servers are never generating outgoing fragments. They may well be fragmented on the path, but the server never stores or usees path mtu values, which could well be forged in an attack. (The root of the problem with path MTU discovery is that there is no reliable way to authenticate ICMP Fragmentation Needed But DF Set messages because they are sent from intermediate routers with their source addresses, and the IMCP payload will not always contain sufficient information to identify a flow.) Recent research in the DNS community showed that it is possible to implement an attack where DNS cache poisoning is feasible by spoofing fragments. This work was done by Amir Herzberg and Haya Shulman: <https://sites.google.com/site/hayashulman/files/fragmentation-poisoning.pdf> This issue was previously discussed among the DNS community, e.g. <http://www.ietf.org/mail-archive/web/dnsext/current/msg01204.html>, without leading to fixes. This patch depends on the patch "ipv4: fix DO and PROBE pmtu mode regarding local fragmentation with UFO/CORK" for the enforcement of the non-fragmentable checks. If other users than ip_append_page/data should use this semantic too, we have to add a new flag to IPCB(skb)->flags to suppress local fragmentation and check for this in ip_finish_output. Many thanks to Florian Weimer for the idea and feedback while implementing this patch. Cc: David S. Miller <davem@davemloft.net> Suggested-by: NFlorian Weimer <fweimer@redhat.com> Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 29 10月, 2013 1 次提交
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由 Hannes Frederic Sowa 提交于
UFO as well as UDP_CORK do not respect IP_PMTUDISC_DO and IP_PMTUDISC_PROBE well enough. UFO enabled packet delivery just appends all frags to the cork and hands it over to the network card. So we just deliver non-DF udp fragments (DF-flag may get overwritten by hardware or virtual UFO enabled interface). UDP_CORK does enqueue the data until the cork is disengaged. At this point it sets the correct IP_DF and local_df flags and hands it over to ip_fragment which in this case will generate an icmp error which gets appended to the error socket queue. This is not reflected in the syscall error (of course, if UFO is enabled this also won't happen). Improve this by checking the pmtudisc flags before appending data to the socket and if we still can fit all data in one packet when IP_PMTUDISC_DO or IP_PMTUDISC_PROBE is set, only then proceed. We use (mtu-fragheaderlen) to check for the maximum length because we ensure not to generate a fragment and non-fragmented data does not need to have its length aligned on 64 bit boundaries. Also the passed in ip_options are already aligned correctly. Maybe, we can relax some other checks around ip_fragment. This needs more research. 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 Jiri Pirko 提交于
Now, if user application does: sendto len<mtu flag MSG_MORE sendto len>mtu flag 0 The skb is not treated as fragmented one because it is not initialized that way. So move the initialization to fix this. introduced by: commit e89e9cf5 "[IPv4/IPv6]: UFO Scatter-gather approach" Signed-off-by: NJiri Pirko <jiri@resnulli.us> Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 29 9月, 2013 1 次提交
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由 Francesco Fusco 提交于
If IP_TOS or IP_TTL are specified as ancillary data, then sendmsg() sends out packets with the specified TTL or TOS overriding the socket values specified with the traditional setsockopt(). The struct inet_cork stores the values of TOS, TTL and priority that are passed through the struct ipcm_cookie. If there are user-specified TOS (tos != -1) or TTL (ttl != 0) in the struct ipcm_cookie, these values are used to override the per-socket values. In case of TOS also the priority is changed accordingly. Two helper functions get_rttos and get_rtconn_flags are defined to take into account the presence of a user specified TOS value when computing RT_TOS and RT_CONN_FLAGS. Signed-off-by: NFrancesco Fusco <ffusco@redhat.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 20 9月, 2013 2 次提交
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由 Ansis Atteka 提交于
If local fragmentation is allowed, then ip_select_ident() and ip_select_ident_more() need to generate unique IDs to ensure correct defragmentation on the peer. For example, if IPsec (tunnel mode) has to encrypt large skbs that have local_df bit set, then all IP fragments that belonged to different ESP datagrams would have used the same identificator. If one of these IP fragments would get lost or reordered, then peer could possibly stitch together wrong IP fragments that did not belong to the same datagram. This would lead to a packet loss or data corruption. Signed-off-by: NAnsis Atteka <aatteka@nicira.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Ansis Atteka 提交于
skb->data already points to IP header, but for the sake of consistency we can also use ip_hdr() to retrieve it. Signed-off-by: NAnsis Atteka <aatteka@nicira.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 14 8月, 2013 1 次提交
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由 Hannes Frederic Sowa 提交于
skb->sk socket can be of AF_INET or AF_INET6 address family. Thus we always have to make sure we a referring to the correct interpretation of skb->sk. We only depend on header defines to query the mtu, so we don't introduce a new dependency to ipv6 by this change. Cc: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>
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- 12 5月, 2013 1 次提交
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由 Denis Efremov 提交于
EXPORT_SYMBOL and inline directives are contradictory to each other. The patch fixes this inconsistency. Found by Linux Driver Verification project (linuxtesting.org). Signed-off-by: NDenis Efremov <yefremov.denis@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 02 4月, 2013 1 次提交
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由 Gao feng 提交于
Signed-off-by: NGao feng <gaofeng@cn.fujitsu.com> Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>
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- 14 2月, 2013 1 次提交
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由 Pravin B Shelar 提交于
Patch cef401de (net: fix possible wrong checksum generation) fixed wrong checksum calculation but it broke TSO by defining new GSO type but not a netdev feature for that type. net_gso_ok() would not allow hardware checksum/segmentation offload of such packets without the feature. Following patch fixes TSO and wrong checksum. This patch uses same logic that Eric Dumazet used. Patch introduces new flag SKBTX_SHARED_FRAG if at least one frag can be modified by the user. but SKBTX_SHARED_FRAG flag is kept in skb shared info tx_flags rather than gso_type. tx_flags is better compared to gso_type since we can have skb with shared frag without gso packet. It does not link SHARED_FRAG to GSO, So there is no need to define netdev feature for this. Signed-off-by: NPravin B Shelar <pshelar@nicira.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 09 12月, 2012 1 次提交
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由 Alexander Duyck 提交于
This change allows the VXLAN to enable Tx checksum offloading even on devices that do not support encapsulated checksum offloads. The advantage to this is that it allows for the lower device to change due to routing table changes without impacting features on the VXLAN itself. Signed-off-by: NAlexander Duyck <alexander.h.duyck@intel.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 09 10月, 2012 1 次提交
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由 Julian Anastasov 提交于
Add new flag to remember when route is via gateway. We will use it to allow rt_gateway to contain address of directly connected host for the cases when DST_NOCACHE is used or when the NH exception caches per-destination route without DST_NOCACHE flag, i.e. when routes are not used for other destinations. By this way we force the neighbour resolving to work with the routed destination but we can use different address in the packet, feature needed for IPVS-DR where original packet for virtual IP is routed via route to real IP. Signed-off-by: NJulian Anastasov <ja@ssi.bg> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 25 9月, 2012 1 次提交
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由 Eric Dumazet 提交于
We currently use a per socket order-0 page cache for tcp_sendmsg() operations. This page is used to build fragments for skbs. Its done to increase probability of coalescing small write() into single segments in skbs still in write queue (not yet sent) But it wastes a lot of memory for applications handling many mostly idle sockets, since each socket holds one page in sk->sk_sndmsg_page Its also quite inefficient to build TSO 64KB packets, because we need about 16 pages per skb on arches where PAGE_SIZE = 4096, so we hit page allocator more than wanted. This patch adds a per task frag allocator and uses bigger pages, if available. An automatic fallback is done in case of memory pressure. (up to 32768 bytes per frag, thats order-3 pages on x86) This increases TCP stream performance by 20% on loopback device, but also benefits on other network devices, since 8x less frags are mapped on transmit and unmapped on tx completion. Alexander Duyck mentioned a probable performance win on systems with IOMMU enabled. Its possible some SG enabled hardware cant cope with bigger fragments, but their ndo_start_xmit() should already handle this, splitting a fragment in sub fragments, since some arches have PAGE_SIZE=65536 Successfully tested on various ethernet devices. (ixgbe, igb, bnx2x, tg3, mellanox mlx4) Signed-off-by: NEric Dumazet <edumazet@google.com> Cc: Ben Hutchings <bhutchings@solarflare.com> Cc: Vijay Subramanian <subramanian.vijay@gmail.com> Cc: Alexander Duyck <alexander.h.duyck@intel.com> Tested-by: NVijay Subramanian <subramanian.vijay@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 27 8月, 2012 1 次提交
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由 Patrick McHardy 提交于
IPv4 conntrack defragments incoming packet at the PRE_ROUTING hook and (in case of forwarded packets) refragments them at POST_ROUTING independent of the IP_DF flag. Refragmentation uses the dst_mtu() of the local route without caring about the original fragment sizes, thereby breaking PMTUD. This patch fixes this by keeping track of the largest received fragment with IP_DF set and generates an ICMP fragmentation required error during refragmentation if that size exceeds the MTU. Signed-off-by: NPatrick McHardy <kaber@trash.net> Acked-by: NEric Dumazet <edumazet@google.com> Acked-by: NDavid S. Miller <davem@davemloft.net>
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- 22 8月, 2012 1 次提交
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由 Eric Dumazet 提交于
Christian Casteyde reported a kmemcheck 32-bit read from uninitialized memory in __ip_select_ident(). It turns out that __ip_make_skb() called ip_select_ident() before properly initializing iph->daddr. This is a bug uncovered by commit 1d861aa4 (inet: Minimize use of cached route inetpeer.) Addresses https://bugzilla.kernel.org/show_bug.cgi?id=46131Reported-by: NChristian Casteyde <casteyde.christian@free.fr> Signed-off-by: NEric Dumazet <edumazet@google.com> Cc: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 11 8月, 2012 1 次提交
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由 Eric Dumazet 提交于
ip_send_skb() can send orphaned skb, so we must pass the net pointer to avoid possible NULL dereference in error path. Bug added by commit 3a7c384f (ipv4: tcp: unicast_sock should not land outside of TCP stack) Signed-off-by: NEric Dumazet <edumazet@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 10 8月, 2012 1 次提交
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由 Eric Dumazet 提交于
commit be9f4a44 (ipv4: tcp: remove per net tcp_sock) added a selinux regression, reported and bisected by John Stultz selinux_ip_postroute_compat() expect to find a valid sk->sk_security pointer, but this field is NULL for unicast_sock It turns out that unicast_sock are really temporary stuff to be able to reuse part of IP stack (ip_append_data()/ip_push_pending_frames()) Fact is that frames sent by ip_send_unicast_reply() should be orphaned to not fool LSM. Note IPv6 never had this problem, as tcp_v6_send_response() doesnt use a fake socket at all. I'll probably implement tcp_v4_send_response() to remove these unicast_sock in linux-3.7 Reported-by: NJohn Stultz <johnstul@us.ibm.com> Bisected-by: NJohn Stultz <johnstul@us.ibm.com> Signed-off-by: NEric Dumazet <edumazet@google.com> Cc: Paul Moore <paul@paul-moore.com> Cc: Eric Paris <eparis@parisplace.org> Cc: "Serge E. Hallyn" <serge@hallyn.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 07 8月, 2012 1 次提交
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由 Vasiliy Kulikov 提交于
__neigh_create() returns either a pointer to struct neighbour or PTR_ERR(). But the caller expects it to return either a pointer or NULL. Replace the NULL check with IS_ERR() check. The bug was introduced in a263b309 ("ipv4: Make neigh lookups directly in output packet path."). Signed-off-by: NVasily Kulikov <segoon@openwall.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 23 7月, 2012 1 次提交
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由 Eric Dumazet 提交于
Set unicast_sock uc_ttl to -1 so that we select the right ttl, instead of sending packets with a 0 ttl. Bug added in commit be9f4a44 (ipv4: tcp: remove per net tcp_sock) Signed-off-by: NHiroaki SHIMODA <shimoda.hiroaki@gmail.com> Signed-off-by: NEric Dumazet <edumazet@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 21 7月, 2012 1 次提交
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由 David S. Miller 提交于
In order to allow prefixed routes, we have to adjust how rt_gateway is set and interpreted. The new interpretation is: 1) rt_gateway == 0, destination is on-link, nexthop is iph->daddr 2) rt_gateway != 0, destination requires a nexthop gateway Abstract the fetching of the proper nexthop value using a new inline helper, rt_nexthop(), as suggested by Joe Perches. Signed-off-by: NDavid S. Miller <davem@davemloft.net> Tested-by: NVijay Subramanian <subramanian.vijay@gmail.com>
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- 20 7月, 2012 1 次提交
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由 Eric Dumazet 提交于
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: NBill Sommerfeld <wsommerfeld@google.com> Signed-off-by: NEric Dumazet <edumazet@google.com> Cc: Tom Herbert <therbert@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 05 7月, 2012 2 次提交
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由 David S. Miller 提交于
When a dst_confirm() happens, mark the confirmation as pending in the dst. Then on the next packet out, when we have the neigh in-hand, do the update. This removes the dependency in dst_confirm() of dst's having an attached neigh. While we're here, remove the explicit 'dst' NULL check, all except 2 or 3 call sites ensure it's not NULL. So just fix those cases up. Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 David S. Miller 提交于
Do not use the dst cached neigh, we'll be getting rid of that. Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 28 6月, 2012 1 次提交
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由 David S. Miller 提交于
Rename it to ip_send_unicast_reply() and add explicit 'saddr' argument. This removed one of the few users of rt->rt_spec_dst. Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 13 6月, 2012 1 次提交
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由 Michel Machado 提交于
Add dev_loopback_xmit() in order to deduplicate functions ip_dev_loopback_xmit() (in net/ipv4/ip_output.c) and ip6_dev_loopback_xmit() (in net/ipv6/ip6_output.c). I was about to reinvent the wheel when I noticed that ip_dev_loopback_xmit() and ip6_dev_loopback_xmit() do exactly what I need and are not IP-only functions, but they were not available to reuse elsewhere. ip6_dev_loopback_xmit() does not have line "skb_dst_force(skb);", but I understand that this is harmless, and should be in dev_loopback_xmit(). Signed-off-by: NMichel Machado <michel@digirati.com.br> CC: "David S. Miller" <davem@davemloft.net> CC: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> CC: James Morris <jmorris@namei.org> CC: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org> CC: Patrick McHardy <kaber@trash.net> CC: Eric Dumazet <edumazet@google.com> CC: Jiri Pirko <jpirko@redhat.com> CC: "Michał Mirosław" <mirq-linux@rere.qmqm.pl> CC: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 04 6月, 2012 1 次提交
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由 Eric Dumazet 提交于
Remove some dropwatch/drop_monitor false positives. Signed-off-by: NEric Dumazet <edumazet@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 16 5月, 2012 1 次提交
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由 Joe Perches 提交于
Standardize the net core ratelimited logging functions. Coalesce formats, align arguments. Change a printk then vprintk sequence to use printf extension %pV. Signed-off-by: NJoe Perches <joe@perches.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 29 3月, 2012 1 次提交
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由 David Howells 提交于
Remove all #inclusions of asm/system.h preparatory to splitting and killing it. Performed with the following command: perl -p -i -e 's!^#\s*include\s*<asm/system[.]h>.*\n!!' `grep -Irl '^#\s*include\s*<asm/system[.]h>' *` Signed-off-by: NDavid Howells <dhowells@redhat.com>
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- 06 12月, 2011 1 次提交
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由 David Miller 提交于
To reflect the fact that a refrence is not obtained to the resulting neighbour entry. Signed-off-by: NDavid S. Miller <davem@davemloft.net> Acked-by: NRoland Dreier <roland@purestorage.com>
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- 02 12月, 2011 1 次提交
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由 Eric Dumazet 提交于
gcc compiler is smart enough to use a single load/store if we memcpy(dptr, sptr, 8) on x86_64, regardless of CONFIG_CC_OPTIMIZE_FOR_SIZE In IP header, daddr immediately follows saddr, this wont change in the future. We only need to make sure our flowi4 (saddr,daddr) fields wont break the rule. Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 24 10月, 2011 1 次提交
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由 Eric Dumazet 提交于
There is a long standing bug in linux tcp stack, about ACK messages sent on behalf of TIME_WAIT sockets. In the IP header of the ACK message, we choose to reflect TOS field of incoming message, and this might break some setups. Example of things that were broken : - Routing using TOS as a selector - Firewalls - Trafic classification / shaping We now remember in timewait structure the inet tos field and use it in ACK generation, and route lookup. Notes : - We still reflect incoming TOS in RST messages. - We could extend MuraliRaja Muniraju patch to report TOS value in netlink messages for TIME_WAIT sockets. - A patch is needed for IPv6 Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 19 10月, 2011 1 次提交
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由 Eric Dumazet 提交于
To ease skb->truesize sanitization, its better to be able to localize all references to skb frags size. Define accessors : skb_frag_size() to fetch frag size, and skb_frag_size_{set|add|sub}() to manipulate it. Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 25 8月, 2011 1 次提交
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由 Ian Campbell 提交于
Signed-off-by: NIan Campbell <ian.campbell@citrix.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> Cc: "Pekka Savola (ipv6)" <pekkas@netcore.fi> Cc: James Morris <jmorris@namei.org> Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org> Cc: Patrick McHardy <kaber@trash.net> Cc: netdev@vger.kernel.org Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 08 8月, 2011 1 次提交
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由 Julian Anastasov 提交于
Make sure skb dst has reference when moving to another context. Currently, I don't see protocols that can hit it when sending broadcasts/multicasts to loopback using noref dsts, so it is just a precaution. Signed-off-by: NJulian Anastasov <ja@ssi.bg> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 03 8月, 2011 1 次提交
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由 Eric Dumazet 提交于
Gergely Kalman reported crashes in check_peer_redir(). It appears commit f39925db (ipv4: Cache learned redirect information in inetpeer.) added a race, leading to possible NULL ptr dereference. Since we can now change dst neighbour, we should make sure a reader can safely use a neighbour. Add RCU protection to dst neighbour, and make sure check_peer_redir() can be called safely by different cpus in parallel. As neighbours are already freed after one RCU grace period, this patch should not add typical RCU penalty (cache cold effects) Many thanks to Gergely for providing a pretty report pointing to the bug. Reported-by: NGergely Kalman <synapse@hippy.csoma.elte.hu> Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 22 7月, 2011 1 次提交
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由 Bill Sommerfeld 提交于
Because the ip fragment offset field counts 8-byte chunks, ip fragments other than the last must contain a multiple of 8 bytes of payload. ip_ufo_append_data wasn't respecting this constraint and, depending on the MTU and ip option sizes, could create malformed non-final fragments. Google-Bug-Id: 5009328 Signed-off-by: NBill Sommerfeld <wsommerfeld@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 18 7月, 2011 1 次提交
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由 David S. Miller 提交于
dst_{get,set}_neighbour() Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 17 7月, 2011 2 次提交
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由 David S. Miller 提交于
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 David S. Miller 提交于
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 14 7月, 2011 1 次提交
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由 David S. Miller 提交于
Now that there is a one-to-one correspondance between neighbour and hh_cache entries, we no longer need: 1) dynamic allocation 2) attachment to dst->hh 3) refcounting Initialization of the hh_cache entry is indicated by hh_len being non-zero, and such initialization is always done with the neighbour's lock held as a writer. Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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