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2016-02-16net: Export ip fragment sysctl to unprivileged usersNikolay Borisov1-4/+0
Now that all the ip fragmentation related sysctls are namespaceified there is no reason to hide them anymore from "root" users inside containers. Signed-off-by: Nikolay Borisov <kernel@kyup.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-16ipv4: namespacify ip fragment max dist sysctl knobNikolay Borisov1-12/+13
Signed-off-by: Nikolay Borisov <kernel@kyup.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-01-28inet: frag: Always orphan skbs inside ip_defrag()Joe Stringer1-0/+1
Later parts of the stack (including fragmentation) expect that there is never a socket attached to frag in a frag_list, however this invariant was not enforced on all defrag paths. This could lead to the BUG_ON(skb->sk) during ip_do_fragment(), as per the call stack at the end of this commit message. While the call could be added to openvswitch to fix this particular error, the head and tail of the frags list are already orphaned indirectly inside ip_defrag(), so it seems like the remaining fragments should all be orphaned in all circumstances. kernel BUG at net/ipv4/ip_output.c:586! [...] Call Trace: <IRQ> [<ffffffffa0205270>] ? do_output.isra.29+0x1b0/0x1b0 [openvswitch] [<ffffffffa02167a7>] ovs_fragment+0xcc/0x214 [openvswitch] [<ffffffff81667830>] ? dst_discard_out+0x20/0x20 [<ffffffff81667810>] ? dst_ifdown+0x80/0x80 [<ffffffffa0212072>] ? find_bucket.isra.2+0x62/0x70 [openvswitch] [<ffffffff810e0ba5>] ? mod_timer_pending+0x65/0x210 [<ffffffff810b732b>] ? __lock_acquire+0x3db/0x1b90 [<ffffffffa03205a2>] ? nf_conntrack_in+0x252/0x500 [nf_conntrack] [<ffffffff810b63c4>] ? __lock_is_held+0x54/0x70 [<ffffffffa02051a3>] do_output.isra.29+0xe3/0x1b0 [openvswitch] [<ffffffffa0206411>] do_execute_actions+0xe11/0x11f0 [openvswitch] [<ffffffff810b63c4>] ? __lock_is_held+0x54/0x70 [<ffffffffa0206822>] ovs_execute_actions+0x32/0xd0 [openvswitch] [<ffffffffa020b505>] ovs_dp_process_packet+0x85/0x140 [openvswitch] [<ffffffff810b63c4>] ? __lock_is_held+0x54/0x70 [<ffffffffa02068a2>] ovs_execute_actions+0xb2/0xd0 [openvswitch] [<ffffffffa020b505>] ovs_dp_process_packet+0x85/0x140 [openvswitch] [<ffffffffa0215019>] ? ovs_ct_get_labels+0x49/0x80 [openvswitch] [<ffffffffa0213a1d>] ovs_vport_receive+0x5d/0xa0 [openvswitch] [<ffffffff810b732b>] ? __lock_acquire+0x3db/0x1b90 [<ffffffff810b732b>] ? __lock_acquire+0x3db/0x1b90 [<ffffffff810b732b>] ? __lock_acquire+0x3db/0x1b90 [<ffffffffa0214895>] ? internal_dev_xmit+0x5/0x140 [openvswitch] [<ffffffffa02148fc>] internal_dev_xmit+0x6c/0x140 [openvswitch] [<ffffffffa0214895>] ? internal_dev_xmit+0x5/0x140 [openvswitch] [<ffffffff81660299>] dev_hard_start_xmit+0x2b9/0x5e0 [<ffffffff8165fc21>] ? netif_skb_features+0xd1/0x1f0 [<ffffffff81660f20>] __dev_queue_xmit+0x800/0x930 [<ffffffff81660770>] ? __dev_queue_xmit+0x50/0x930 [<ffffffff810b53f1>] ? mark_held_locks+0x71/0x90 [<ffffffff81669876>] ? neigh_resolve_output+0x106/0x220 [<ffffffff81661060>] dev_queue_xmit+0x10/0x20 [<ffffffff816698e8>] neigh_resolve_output+0x178/0x220 [<ffffffff816a8e6f>] ? ip_finish_output2+0x1ff/0x590 [<ffffffff816a8e6f>] ip_finish_output2+0x1ff/0x590 [<ffffffff816a8cee>] ? ip_finish_output2+0x7e/0x590 [<ffffffff816a9a31>] ip_do_fragment+0x831/0x8a0 [<ffffffff816a8c70>] ? ip_copy_metadata+0x1b0/0x1b0 [<ffffffff816a9ae3>] ip_fragment.constprop.49+0x43/0x80 [<ffffffff816a9c9c>] ip_finish_output+0x17c/0x340 [<ffffffff8169a6f4>] ? nf_hook_slow+0xe4/0x190 [<ffffffff816ab4c0>] ip_output+0x70/0x110 [<ffffffff816a9b20>] ? ip_fragment.constprop.49+0x80/0x80 [<ffffffff816aa9f9>] ip_local_out+0x39/0x70 [<ffffffff816abf89>] ip_send_skb+0x19/0x40 [<ffffffff816abfe3>] ip_push_pending_frames+0x33/0x40 [<ffffffff816df21a>] icmp_push_reply+0xea/0x120 [<ffffffff816df93d>] icmp_reply.constprop.23+0x1ed/0x230 [<ffffffff816df9ce>] icmp_echo.part.21+0x4e/0x50 [<ffffffff810b63c4>] ? __lock_is_held+0x54/0x70 [<ffffffff810d5f9e>] ? rcu_read_lock_held+0x5e/0x70 [<ffffffff816dfa06>] icmp_echo+0x36/0x70 [<ffffffff816e0d11>] icmp_rcv+0x271/0x450 [<ffffffff816a4ca7>] ip_local_deliver_finish+0x127/0x3a0 [<ffffffff816a4bc1>] ? ip_local_deliver_finish+0x41/0x3a0 [<ffffffff816a5160>] ip_local_deliver+0x60/0xd0 [<ffffffff816a4b80>] ? ip_rcv_finish+0x560/0x560 [<ffffffff816a46fd>] ip_rcv_finish+0xdd/0x560 [<ffffffff816a5453>] ip_rcv+0x283/0x3e0 [<ffffffff810b6302>] ? match_held_lock+0x192/0x200 [<ffffffff816a4620>] ? inet_del_offload+0x40/0x40 [<ffffffff8165d062>] __netif_receive_skb_core+0x392/0xae0 [<ffffffff8165e68e>] ? process_backlog+0x8e/0x230 [<ffffffff810b53f1>] ? mark_held_locks+0x71/0x90 [<ffffffff8165d7c8>] __netif_receive_skb+0x18/0x60 [<ffffffff8165e678>] process_backlog+0x78/0x230 [<ffffffff8165e6dd>] ? process_backlog+0xdd/0x230 [<ffffffff8165e355>] net_rx_action+0x155/0x400 [<ffffffff8106b48c>] __do_softirq+0xcc/0x420 [<ffffffff816a8e87>] ? ip_finish_output2+0x217/0x590 [<ffffffff8178e78c>] do_softirq_own_stack+0x1c/0x30 <EOI> [<ffffffff8106b88e>] do_softirq+0x4e/0x60 [<ffffffff8106b948>] __local_bh_enable_ip+0xa8/0xb0 [<ffffffff816a8eb0>] ip_finish_output2+0x240/0x590 [<ffffffff816a9a31>] ? ip_do_fragment+0x831/0x8a0 [<ffffffff816a9a31>] ip_do_fragment+0x831/0x8a0 [<ffffffff816a8c70>] ? ip_copy_metadata+0x1b0/0x1b0 [<ffffffff816a9ae3>] ip_fragment.constprop.49+0x43/0x80 [<ffffffff816a9c9c>] ip_finish_output+0x17c/0x340 [<ffffffff8169a6f4>] ? nf_hook_slow+0xe4/0x190 [<ffffffff816ab4c0>] ip_output+0x70/0x110 [<ffffffff816a9b20>] ? ip_fragment.constprop.49+0x80/0x80 [<ffffffff816aa9f9>] ip_local_out+0x39/0x70 [<ffffffff816abf89>] ip_send_skb+0x19/0x40 [<ffffffff816abfe3>] ip_push_pending_frames+0x33/0x40 [<ffffffff816d55d3>] raw_sendmsg+0x7d3/0xc30 [<ffffffff810b732b>] ? __lock_acquire+0x3db/0x1b90 [<ffffffff816e7557>] ? inet_sendmsg+0xc7/0x1d0 [<ffffffff810b63c4>] ? __lock_is_held+0x54/0x70 [<ffffffff816e759a>] inet_sendmsg+0x10a/0x1d0 [<ffffffff816e7495>] ? inet_sendmsg+0x5/0x1d0 [<ffffffff8163e398>] sock_sendmsg+0x38/0x50 [<ffffffff8163ec5f>] ___sys_sendmsg+0x25f/0x270 [<ffffffff811aadad>] ? handle_mm_fault+0x8dd/0x1320 [<ffffffff8178c147>] ? _raw_spin_unlock+0x27/0x40 [<ffffffff810529b2>] ? __do_page_fault+0x1e2/0x460 [<ffffffff81204886>] ? __fget_light+0x66/0x90 [<ffffffff8163f8e2>] __sys_sendmsg+0x42/0x80 [<ffffffff8163f932>] SyS_sendmsg+0x12/0x20 [<ffffffff8178cb17>] entry_SYSCALL_64_fastpath+0x12/0x6f Code: 00 00 44 89 e0 e9 7c fb ff ff 4c 89 ff e8 e7 e7 ff ff 41 8b 9d 80 00 00 00 2b 5d d4 89 d8 c1 f8 03 0f b7 c0 e9 33 ff ff f 66 66 66 2e 0f 1f 84 00 00 00 00 00 66 66 66 66 90 55 48 RIP [<ffffffff816a9a92>] ip_do_fragment+0x892/0x8a0 RSP <ffff88006d603170> Fixes: 7f8a436eaa2c ("openvswitch: Add conntrack action") Signed-off-by: Joe Stringer <joe@ovn.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-01-05inet: kill unused skb_free opFlorian Westphal1-1/+0
The only user was removed in commit 029f7f3b8701cc7a ("netfilter: ipv6: nf_defrag: avoid/free clone operations"). Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-02net: fix percpu memory leaksEric Dumazet1-3/+9
This patch fixes following problems : 1) percpu_counter_init() can return an error, therefore init_frag_mem_limit() must propagate this error so that inet_frags_init_net() can do the same up to its callers. 2) If ip[46]_frags_ns_ctl_register() fail, we must unwind properly and free the percpu_counter. Without this fix, we leave freed object in percpu_counters global list (if CONFIG_HOTPLUG_CPU) leading to crashes. This bug was detected by KASAN and syzkaller tool (http://github.com/google/syzkaller) Fixes: 6d7b857d541e ("net: use lib/percpu_counter API for fragmentation mem accounting") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Dmitry Vyukov <dvyukov@google.com> Cc: Hannes Frederic Sowa <hannes@stressinduktion.org> Cc: Jesper Dangaard Brouer <brouer@redhat.com> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-12ipv4: Pass struct net into ip_defrag and ip_check_defragEric W. Biederman1-4/+3
The function ip_defrag is called on both the input and the output paths of the networking stack. In particular conntrack when it is tracking outbound packets from the local machine calls ip_defrag. So add a struct net parameter and stop making ip_defrag guess which network namespace it needs to defragment packets in. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Acked-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-29net: Replace vrf_master_ifindex{, _rcu} with l3mdev equivalentsDavid Ahern1-3/+3
Replace calls to vrf_master_ifindex_rcu and vrf_master_ifindex with either l3mdev_master_ifindex_rcu or l3mdev_master_ifindex. The pattern: oif = vrf_master_ifindex(dev) ? : dev->ifindex; is replaced with oif = l3mdev_fib_oif(dev); And remove the now unused vrf macros. Signed-off-by: David Ahern <dsa@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-28net: Add support for VRFs to inetpeer cacheDavid Ahern1-1/+2
inetpeer caches based on address only, so duplicate IP addresses within a namespace return the same cached entry. Enhance the ipv4 address key to contain both the IPv4 address and VRF device index. Signed-off-by: David Ahern <dsa@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-13net: frags: Add VRF device index to cache and lookupDavid Ahern1-5/+13
Fragmentation cache uses information from the IP header to reassemble packets. That information can be duplicated across VRFs -- same source and destination addresses, protocol and id. Handle fragmentation with VRFs by adding the VRF device index to entries in the cache and the lookup arg. Signed-off-by: David Ahern <dsa@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-31Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-6/+6
Conflicts: arch/s390/net/bpf_jit_comp.c drivers/net/ethernet/ti/netcp_ethss.c net/bridge/br_multicast.c net/ipv4/ip_fragment.c All four conflicts were cases of simple overlapping changes. Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-26inet: frags: remove INET_FRAG_EVICTED and use list_evictor for the testNikolay Aleksandrov1-1/+1
We can simply remove the INET_FRAG_EVICTED flag to avoid all the flags race conditions with the evictor and use a participation test for the evictor list, when we're at that point (after inet_frag_kill) in the timer there're 2 possible cases: 1. The evictor added the entry to its evictor list while the timer was waiting for the chainlock or 2. The timer unchained the entry and the evictor won't see it In both cases we should be able to see list_evictor correctly due to the sync on the chainlock. Joint work with Florian Westphal. Tested-by: Frank Schreuder <fschreuder@transip.nl> Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-26inet: frag: change *_frag_mem_limit functions to take netns_frags as argumentFlorian Westphal1-5/+5
Followup patch will call it after inet_frag_queue was freed, so q->net doesn't work anymore (but netf = q->net; free(q); mem_limit(netf) would). Tested-by: Frank Schreuder <fschreuder@transip.nl> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-23Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-2/+4
Conflicts: net/bridge/br_mdb.c br_mdb.c conflict was a function call being removed to fix a bug in 'net' but whose signature was changed in 'net-next'. Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-21inet: frags: fix defragmented packet's IP header for af_packetEdward Hyunkoo Jee1-2/+4
When ip_frag_queue() computes positions, it assumes that the passed sk_buff does not contain L2 headers. However, when PACKET_FANOUT_FLAG_DEFRAG is used, IP reassembly functions can be called on outgoing packets that contain L2 headers. Also, IPv4 checksum is not corrected after reassembly. Fixes: 7736d33f4262 ("packet: Add pre-defragmentation support for ipv4 fanouts.") Signed-off-by: Edward Hyunkoo Jee <edjee@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Willem de Bruijn <willemb@google.com> Cc: Jerry Chu <hkchu@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-11Revert "ipv4: use skb coalescing in defragmentation"Florian Westphal1-20/+6
This reverts commit 3cc4949269e01f39443d0fcfffb5bc6b47878d45. There is nothing wrong with coalescing during defragmentation, it reduces truesize overhead and simplifies things for the receiving socket (no fraglist walk needed). However, it also destroys geometry of the original fragments. While that doesn't cause any breakage (we make sure to not exceed largest original size) ip_do_fragment contains a 'fastpath' that takes advantage of a present frag list and results in fragments that (in most cases) match what was received. In case its needed the coalescing could be done later, when we're sure the skb is not forwarded. But discussion during NFWS resulted in 'lets just remove this for now'. Cc: Eric Dumazet <edumazet@google.com> Signed-off-by: Florian Westphal <fw@strlen.de> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-27ip_fragment: don't forward defragmented DF packetFlorian Westphal1-5/+26
We currently always send fragments without DF bit set. Thus, given following setup: mtu1500 - mtu1500:1400 - mtu1400:1280 - mtu1280 A R1 R2 B Where R1 and R2 run linux with netfilter defragmentation/conntrack enabled, then if Host A sent a fragmented packet _with_ DF set to B, R1 will respond with icmp too big error if one of these fragments exceeded 1400 bytes. However, if R1 receives fragment sizes 1200 and 100, it would forward the reassembled packet without refragmenting, i.e. R2 will send an icmp error in response to a packet that was never sent, citing mtu that the original sender never exceeded. The other minor issue is that a refragmentation on R1 will conceal the MTU of R2-B since refragmentation does not set DF bit on the fragments. This modifies ip_fragment so that we track largest fragment size seen both for DF and non-DF packets, and set frag_max_size to the largest value. If the DF fragment size is larger or equal to the non-df one, we will consider the packet a path mtu probe: We set DF bit on the reassembled skb and also tag it with a new IPCB flag to force refragmentation even if skb fits outdev mtu. We will also set DF bit on each fragment in this case. Joint work with Hannes Frederic Sowa. Reported-by: Jesse Gross <jesse@nicira.com> Signed-off-by: Florian Westphal <fw@strlen.de> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-19IPv4: skip ICMP for bridge contrack users when defrag expiresAndy Zhou1-1/+3
users in [IP_DEFRAG_CONNTRACK_BRIDGE_IN, __IP_DEFRAG_CONNTRACK_BR_IN] should not ICMP message also. Reported-by: Florian Westphal <fw@strlen.de> Signed-off-by: Andy Zhou <azhou@nicira.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-19ipv4: introduce frag_expire_skip_icmp()Andy Zhou1-4/+9
Improve readability of skip ICMP for de-fragmentation expiration logic. This change will also make the logic easier to maintain when the following patches in this series are applied. Signed-off-by: Andy Zhou <azhou@nicira.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-03ipv4: coding style: comparison for inequality with NULLIan Morris1-1/+2
The ipv4 code uses a mixture of coding styles. In some instances check for non-NULL pointer is done as x != NULL and sometimes as x. x is preferred according to checkpatch and this patch makes the code consistent by adopting the latter form. No changes detected by objdiff. Signed-off-by: Ian Morris <ipm@chirality.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-03ipv4: coding style: comparison for equality with NULLIan Morris1-5/+6
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>
2015-03-05ipv4: ip_check_defrag should not assume that skb_network_offset is zeroAlexander Drozdov1-4/+7
ip_check_defrag() may be used by af_packet to defragment outgoing packets. skb_network_offset() of af_packet's outgoing packets is not zero. Signed-off-by: Alexander Drozdov <al.drozdov@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-02-20ipv4: ip_check_defrag should correctly check return value of skb_copy_bitsAlexander Drozdov1-1/+1
skb_copy_bits() returns zero on success and negative value on error, so it is needed to invert the condition in ip_check_defrag(). Fixes: 1bf3751ec90c ("ipv4: ip_check_defrag must not modify skb before unsharing") Signed-off-by: Alexander Drozdov <al.drozdov@gmail.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-11-11net: Convert LIMIT_NETDEBUG to net_dbg_ratelimitedJoe Perches1-2/+1
Use the more common dynamic_debug capable net_dbg_ratelimited and remove the LIMIT_NETDEBUG macro. All messages are still ratelimited. Some KERN_<LEVEL> uses are changed to KERN_DEBUG. This may have some negative impact on messages that were emitted at KERN_INFO that are not not enabled at all unless DEBUG is defined or dynamic_debug is enabled. Even so, these messages are now _not_ emitted by default. This also eliminates the use of the net_msg_warn sysctl "/proc/sys/net/core/warnings". For backward compatibility, the sysctl is not removed, but it has no function. The extern declaration of net_msg_warn is removed from sock.h and made static in net/core/sysctl_net_core.c Miscellanea: o Update the sysctl documentation o Remove the embedded uses of pr_fmt o Coalesce format fragments o Realign arguments Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-11-04inet: frags: remove inline on static in c fileFabian Frederick1-8/+8
remove __inline__ / inline and let compiler decide what to do with static functions Inspired-by: "David S. Miller" <davem@davemloft.net> Signed-off-by: Fabian Frederick <fabf@skynet.be> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-01inet: frags: add __init to ip4_frags_ctl_registerFabian Frederick1-2/+2
ip4_frags_ctl_register is only called by __init ipfrag_init Signed-off-by: Fabian Frederick <fabf@skynet.be> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-02inet: frags: use kmem_cache for inet_frag_queueNikolay Aleksandrov1-1/+4
Use kmem_cache to allocate/free inet_frag_queue objects since they're all the same size per inet_frags user and are alloced/freed in high volumes thus making it a perfect case for kmem_cache. Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com> Acked-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-02inet: frags: use INET_FRAG_EVICTED to prevent icmp messagesNikolay Aleksandrov1-7/+7
Now that we have INET_FRAG_EVICTED we might as well use it to stop sending icmp messages in the "frag_expire" functions instead of stripping INET_FRAG_FIRST_IN from their flags when evicting. Also fix the comment style in ip6_expire_frag_queue(). Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com> Reviewed-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-02inet: frags: rename last_in to flagsNikolay Aleksandrov1-10/+10
The last_in field has been used to store various flags different from first/last frag in so give it a more descriptive name: flags. Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-27inet: frag: set limits and make init_net's high_thresh limit globalNikolay Aleksandrov1-2/+8
This patch makes init_net's high_thresh limit to be the maximum for all namespaces, thus introducing a global memory limit threshold equal to the sum of the individual high_thresh limits which are capped. It also introduces some sane minimums for low_thresh as it shouldn't be able to drop below 0 (or > high_thresh in the unsigned case), and overall low_thresh should not ever be above high_thresh, so we make the following relations for a namespace: init_net: high_thresh - max(not capped), min(init_net low_thresh) low_thresh - max(init_net high_thresh), min (0) all other namespaces: high_thresh = max(init_net high_thresh), min(namespace's low_thresh) low_thresh = max(namespace's high_thresh), min(0) The major issue with having low_thresh > high_thresh is that we'll schedule eviction but never evict anything and thus rely only on the timers. Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-27inet: frag: use seqlock for hash rebuildFlorian Westphal1-1/+0
rehash is rare operation, don't force readers to take the read-side rwlock. Instead, we only have to detect the (rare) case where the secret was altered while we are trying to insert a new inetfrag queue into the table. If it was changed, drop the bucket lock and recompute the hash to get the 'new' chain bucket that we have to insert into. Joint work with Nikolay Aleksandrov. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-27inet: frag: remove periodic secret rebuild timerFlorian Westphal1-2/+3
merge functionality into the eviction workqueue. Instead of rebuilding every n seconds, take advantage of the upper hash chain length limit. If we hit it, mark table for rebuild and schedule workqueue. To prevent frequent rebuilds when we're completely overloaded, don't rebuild more than once every 5 seconds. ipfrag_secret_interval sysctl is now obsolete and has been marked as deprecated, it still can be changed so scripts won't be broken but it won't have any effect. A comment is left above each unused secret_timer variable to avoid confusion. Joint work with Nikolay Aleksandrov. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-27inet: frag: remove lru listFlorian Westphal1-1/+0
no longer used. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-27inet: frag: don't account number of fragment queuesFlorian Westphal1-5/+0
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: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-27inet: frag: move eviction of queues to work queueFlorian Westphal1-1/+2
When the high_thresh limit is reached we try to toss the 'oldest' incomplete fragment queues until memory limits are below the low_thresh value. This happens in softirq/packet processing context. This has two drawbacks: 1) processors might evict a queue that was about to be completed by another cpu, because they will compete wrt. resource usage and resource reclaim. 2) LRU list maintenance is expensive. But when constantly overloaded, even the 'least recently used' element is recent, so removing 'lru' queue first is not 'fairer' than removing any other fragment queue. This moves eviction out of the fast path: When the low threshold is reached, a work queue is scheduled which then iterates over the table and removes the queues that exceed the memory limits of the namespace. It sets a new flag called INET_FRAG_EVICTED on the evicted queues so the proper counters will get incremented when the queue is forcefully expired. When the high threshold is reached, no more fragment queues are created until we're below the limit again. The LRU list is now unused and will be removed in a followup patch. Joint work with Nikolay Aleksandrov. Suggested-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-27inet: frag: move evictor calls into frag_find functionFlorian Westphal1-15/+0
First step to move eviction handling into a work queue. We lose two spots that accounted evicted fragments in MIB counters. Accounting will be restored since the upcoming work-queue evictor invokes the frag queue timer callbacks instead. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-27inet: frag: remove hash size assumptions from callersFlorian Westphal1-1/+1
hide actual hash size from individual users: The _find function will now fold the given hash value into the required range. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-27inet: frag: constify match, hashfn and constructor argumentsFlorian Westphal1-7/+7
Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-05-05ipv4: fix "conntrack zones" support for defrag user check in ip_expireVasily Averin1-2/+3
Defrag user check in ip_expire was not updated after adding support for "conntrack zones". This bug manifests as a RFC violation, since the router will send the icmp time exceeeded message when using conntrack zones. Signed-off-by: Vasily Averin <vvs@openvz.org> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-12-17net: Add utility functions to clear rxhashTom Herbert1-1/+1
In several places 'skb->rxhash = 0' is being done to clear the rxhash value in an skb. This does not clear l4_rxhash which could still be set so that the rxhash wouldn't be recalculated on subsequent call to skb_get_rxhash. This patch adds an explict function to clear all the rxhash related information in the skb properly. skb_clear_hash_if_not_l4 clears the rxhash only if it is not marked as l4_rxhash. Fixed up places where 'skb->rxhash = 0' was being called. Signed-off-by: Tom Herbert <therbert@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-23ipv4: initialize ip4_frags hash secret as late as possibleHannes Frederic Sowa1-0/+1
Defer the generation of the first hash secret for the ipv4 fragmentation cache as late as possible. ip4_frags.rnd gets initial seeded by inet_frags_init and regulary reseeded by inet_frag_secret_rebuild. Either we call ipqhashfn directly from ip_fragment.c in which case we initialize the secret directly. If we first get called by inet_frag_secret_rebuild we install a new secret by a manual call to get_random_bytes. This secret will be overwritten as soon as the first call to ipqhashfn happens. This is safe because we won't race while publishing the new secrets with anyone else. Cc: Eric Dumazet <edumazet@google.com> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-22Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-4/+10
Conflicts: drivers/net/ethernet/emulex/benet/be_main.c drivers/net/ethernet/intel/igb/igb_main.c drivers/net/wireless/brcm80211/brcmsmac/mac80211_if.c include/net/scm.h net/batman-adv/routing.c net/ipv4/tcp_input.c The e{uid,gid} --> {uid,gid} credentials fix conflicted with the cleanup in net-next to now pass cred structs around. The be2net driver had a bug fix in 'net' that overlapped with the VLAN interface changes by Patrick McHardy in net-next. An IGB conflict existed because in 'net' the build_skb() support was reverted, and in 'net-next' there was a comment style fix within that code. Several batman-adv conflicts were resolved by making sure that all calls to batadv_is_my_mac() are changed to have a new bat_priv first argument. Eric Dumazet's TS ECR fix in TCP in 'net' conflicted with the F-RTO rewrite in 'net-next', mostly overlapping changes. Thanks to Stephen Rothwell and Antonio Quartulli for help with several of these merge resolutions. Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-17net: drop dst before queueing fragmentsEric Dumazet1-4/+10
Commit 4a94445c9a5c (net: Use ip_route_input_noref() in input path) added a bug in IP defragmentation handling, as non refcounted dst could escape an RCU protected section. Commit 64f3b9e203bd068 (net: ip_expire() must revalidate route) fixed the case of timeouts, but not the general problem. Tom Parkin noticed crashes in UDP stack and provided a patch, but further analysis permitted us to pinpoint the root cause. Before queueing a packet into a frag list, we must drop its dst, as this dst has limited lifetime (RCU protected) When/if a packet is finally reassembled, we use the dst of the very last skb, still protected by RCU and valid, as the dst of the reassembled packet. Use same logic in IPv6, as there is no need to hold dst references. Reported-by: Tom Parkin <tparkin@katalix.com> Tested-by: Tom Parkin <tparkin@katalix.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-24inet: generalize ipv4-only RFC3168 5.3 ecn fragmentation handling for future use by ipv6Hannes Frederic Sowa1-30/+1
This patch just moves some code arround to make the ip4_frag_ecn_table and IPFRAG_ECN_* constants accessible from the other reassembly engines. I also renamed ip4_frag_ecn_table to ip_frag_ecn_table. Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Jesper Dangaard Brouer <jbrouer@redhat.com> Cc: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Acked-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-19inet: limit length of fragment queue hash table bucket listsHannes Frederic Sowa1-7/+4
This patch introduces a constant limit of the fragment queue hash table bucket list lengths. Currently the limit 128 is choosen somewhat arbitrary and just ensures that we can fill up the fragment cache with empty packets up to the default ip_frag_high_thresh limits. It should just protect from list iteration eating considerable amounts of cpu. If we reach the maximum length in one hash bucket a warning is printed. This is implemented on the caller side of inet_frag_find to distinguish between the different users of inet_fragment.c. I dropped the out of memory warning in the ipv4 fragment lookup path, because we already get a warning by the slab allocator. Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Jesper Dangaard Brouer <jbrouer@redhat.com> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-02-15net: Add skb_unclone() helper function.Pravin B Shelar1-1/+1
This function will be used in next GRE_GSO patch. This patch does not change any functionality. Signed-off-by: Pravin B Shelar <pshelar@nicira.com> Acked-by: Eric Dumazet <edumazet@google.com>
2013-01-29net: frag, move LRU list maintenance outside of rwlockJesper Dangaard Brouer1-3/+1
Updating the fragmentation queues LRU (Least-Recently-Used) list, required taking the hash writer lock. However, the LRU list isn't tied to the hash at all, so we can use a separate lock for it. Original-idea-by: Florian Westphal <fw@strlen.de> Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-01-29net: frag helper functions for mem limit trackingJesper Dangaard Brouer1-13/+11
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: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-01-17net: increase fragment memory usage limitsJesper Dangaard Brouer1-7/+15
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: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-12-12Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-nextLinus Torvalds1-0/+4
Pull networking changes from David Miller: 1) Allow to dump, monitor, and change the bridge multicast database using netlink. From Cong Wang. 2) RFC 5961 TCP blind data injection attack mitigation, from Eric Dumazet. 3) Networking user namespace support from Eric W. Biederman. 4) tuntap/virtio-net multiqueue support by Jason Wang. 5) Support for checksum offload of encapsulated packets (basically, tunneled traffic can still be checksummed by HW). From Joseph Gasparakis. 6) Allow BPF filter access to VLAN tags, from Eric Dumazet and Daniel Borkmann. 7) Bridge port parameters over netlink and BPDU blocking support from Stephen Hemminger. 8) Improve data access patterns during inet socket demux by rearranging socket layout, from Eric Dumazet. 9) TIPC protocol updates and cleanups from Ying Xue, Paul Gortmaker, and Jon Maloy. 10) Update TCP socket hash sizing to be more in line with current day realities. The existing heurstics were choosen a decade ago. From Eric Dumazet. 11) Fix races, queue bloat, and excessive wakeups in ATM and associated drivers, from Krzysztof Mazur and David Woodhouse. 12) Support DOVE (Distributed Overlay Virtual Ethernet) extensions in VXLAN driver, from David Stevens. 13) Add "oops_only" mode to netconsole, from Amerigo Wang. 14) Support set and query of VEB/VEPA bridge mode via PF_BRIDGE, also allow DCB netlink to work on namespaces other than the initial namespace. From John Fastabend. 15) Support PTP in the Tigon3 driver, from Matt Carlson. 16) tun/vhost zero copy fixes and improvements, plus turn it on by default, from Michael S. Tsirkin. 17) Support per-association statistics in SCTP, from Michele Baldessari. And many, many, driver updates, cleanups, and improvements. Too numerous to mention individually. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1722 commits) net/mlx4_en: Add support for destination MAC in steering rules net/mlx4_en: Use generic etherdevice.h functions. net: ethtool: Add destination MAC address to flow steering API bridge: add support of adding and deleting mdb entries bridge: notify mdb changes via netlink ndisc: Unexport ndisc_{build,send}_skb(). uapi: add missing netconf.h to export list pkt_sched: avoid requeues if possible solos-pci: fix double-free of TX skb in DMA mode bnx2: Fix accidental reversions. bna: Driver Version Updated to 3.1.2.1 bna: Firmware update bna: Add RX State bna: Rx Page Based Allocation bna: TX Intr Coalescing Fix bna: Tx and Rx Optimizations bna: Code Cleanup and Enhancements ath9k: check pdata variable before dereferencing it ath5k: RX timestamp is reported at end of frame ath9k_htc: RX timestamp is reported at end of frame ...
2012-12-10ipv4: ip_check_defrag must not modify skb before unsharingJohannes Berg1-10/+9
ip_check_defrag() might be called from af_packet within the RX path where shared SKBs are used, so it must not modify the input SKB before it has unshared it for defragmentation. Use skb_copy_bits() to get the IP header and only pull in everything later. The same is true for the other caller in macvlan as it is called from dev->rx_handler which can also get a shared SKB. Reported-by: Eric Leblond <eric@regit.org> Cc: stable@vger.kernel.org Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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