1. 01 4月, 2018 9 次提交
    • E
      inet: frags: reorganize struct netns_frags · c2615cf5
      Eric Dumazet 提交于
      Put the read-mostly fields in a separate cache line
      at the beginning of struct netns_frags, to reduce
      false sharing noticed in inet_frag_kill()
      Signed-off-by: NEric Dumazet <edumazet@google.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      c2615cf5
    • E
      inet: frags: break the 2GB limit for frags storage · 3e67f106
      Eric Dumazet 提交于
      Some users are willing to provision huge amounts of memory to be able
      to perform reassembly reasonnably well under pressure.
      
      Current memory tracking is using one atomic_t and integers.
      
      Switch to atomic_long_t so that 64bit arches can use more than 2GB,
      without any cost for 32bit arches.
      
      Note that this patch avoids an overflow error, if high_thresh was set
      to ~2GB, since this test in inet_frag_alloc() was never true :
      
      if (... || frag_mem_limit(nf) > nf->high_thresh)
      
      Tested:
      
      $ echo 16000000000 >/proc/sys/net/ipv4/ipfrag_high_thresh
      
      <frag DDOS>
      
      $ grep FRAG /proc/net/sockstat
      FRAG: inuse 14705885 memory 16000002880
      
      $ nstat -n ; sleep 1 ; nstat | grep Reas
      IpReasmReqds                    3317150            0.0
      IpReasmFails                    3317112            0.0
      Signed-off-by: NEric Dumazet <edumazet@google.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      3e67f106
    • E
      inet: frags: remove inet_frag_maybe_warn_overflow() · 2d44ed22
      Eric Dumazet 提交于
      This function is obsolete, after rhashtable addition to inet defrag.
      Signed-off-by: NEric Dumazet <edumazet@google.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      2d44ed22
    • E
      inet: frags: get rif of inet_frag_evicting() · 399d1404
      Eric Dumazet 提交于
      This refactors ip_expire() since one indentation level is removed.
      
      Note: in the future, we should try hard to avoid the skb_clone()
      since this is a serious performance cost.
      Under DDOS, the ICMP message wont be sent because of rate limits.
      
      Fact that ip6_expire_frag_queue() does not use skb_clone() is
      disturbing too. Presumably IPv6 should have the same
      issue than the one we fixed in commit ec4fbd64
      ("inet: frag: release spinlock before calling icmp_send()")
      Signed-off-by: NEric Dumazet <edumazet@google.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      399d1404
    • E
      inet: frags: remove some helpers · 6befe4a7
      Eric Dumazet 提交于
      Remove sum_frag_mem_limit(), ip_frag_mem() & ip6_frag_mem()
      
      Also since we use rhashtable we can bring back the number of fragments
      in "grep FRAG /proc/net/sockstat /proc/net/sockstat6" that was
      removed in commit 434d3054 ("inet: frag: don't account number
      of fragment queues")
      Signed-off-by: NEric Dumazet <edumazet@google.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      6befe4a7
    • E
      inet: frags: use rhashtables for reassembly units · 648700f7
      Eric Dumazet 提交于
      Some applications still rely on IP fragmentation, and to be fair linux
      reassembly unit is not working under any serious load.
      
      It uses static hash tables of 1024 buckets, and up to 128 items per bucket (!!!)
      
      A work queue is supposed to garbage collect items when host is under memory
      pressure, and doing a hash rebuild, changing seed used in hash computations.
      
      This work queue blocks softirqs for up to 25 ms when doing a hash rebuild,
      occurring every 5 seconds if host is under fire.
      
      Then there is the problem of sharing this hash table for all netns.
      
      It is time to switch to rhashtables, and allocate one of them per netns
      to speedup netns dismantle, since this is a critical metric these days.
      
      Lookup is now using RCU. A followup patch will even remove
      the refcount hold/release left from prior implementation and save
      a couple of atomic operations.
      
      Before this patch, 16 cpus (16 RX queue NIC) could not handle more
      than 1 Mpps frags DDOS.
      
      After the patch, I reach 9 Mpps without any tuning, and can use up to 2GB
      of storage for the fragments (exact number depends on frags being evicted
      after timeout)
      
      $ grep FRAG /proc/net/sockstat
      FRAG: inuse 1966916 memory 2140004608
      
      A followup patch will change the limits for 64bit arches.
      Signed-off-by: NEric Dumazet <edumazet@google.com>
      Cc: Kirill Tkhai <ktkhai@virtuozzo.com>
      Cc: Herbert Xu <herbert@gondor.apana.org.au>
      Cc: Florian Westphal <fw@strlen.de>
      Cc: Jesper Dangaard Brouer <brouer@redhat.com>
      Cc: Alexander Aring <alex.aring@gmail.com>
      Cc: Stefan Schmidt <stefan@osg.samsung.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      648700f7
    • E
      inet: frags: add a pointer to struct netns_frags · 093ba729
      Eric Dumazet 提交于
      In order to simplify the API, add a pointer to struct inet_frags.
      This will allow us to make things less complex.
      
      These functions no longer have a struct inet_frags parameter :
      
      inet_frag_destroy(struct inet_frag_queue *q  /*, struct inet_frags *f */)
      inet_frag_put(struct inet_frag_queue *q /*, struct inet_frags *f */)
      inet_frag_kill(struct inet_frag_queue *q /*, struct inet_frags *f */)
      inet_frags_exit_net(struct netns_frags *nf /*, struct inet_frags *f */)
      ip6_expire_frag_queue(struct net *net, struct frag_queue *fq)
      Signed-off-by: NEric Dumazet <edumazet@google.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      093ba729
    • E
      inet: frags: change inet_frags_init_net() return value · 787bea77
      Eric Dumazet 提交于
      We will soon initialize one rhashtable per struct netns_frags
      in inet_frags_init_net().
      
      This patch changes the return value to eventually propagate an
      error.
      Signed-off-by: NEric Dumazet <edumazet@google.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      787bea77
    • E
      ipv6: frag: remove unused field · c22af22c
      Eric Dumazet 提交于
      csum field in struct frag_queue is not used, remove it.
      Signed-off-by: NEric Dumazet <edumazet@google.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      c22af22c
  2. 31 3月, 2018 2 次提交
    • A
      bpf: Hooks for sys_connect · d74bad4e
      Andrey Ignatov 提交于
      == The problem ==
      
      See description of the problem in the initial patch of this patch set.
      
      == The solution ==
      
      The patch provides much more reliable in-kernel solution for the 2nd
      part of the problem: making outgoing connecttion from desired IP.
      
      It adds new attach types `BPF_CGROUP_INET4_CONNECT` and
      `BPF_CGROUP_INET6_CONNECT` for program type
      `BPF_PROG_TYPE_CGROUP_SOCK_ADDR` that can be used to override both
      source and destination of a connection at connect(2) time.
      
      Local end of connection can be bound to desired IP using newly
      introduced BPF-helper `bpf_bind()`. It allows to bind to only IP though,
      and doesn't support binding to port, i.e. leverages
      `IP_BIND_ADDRESS_NO_PORT` socket option. There are two reasons for this:
      * looking for a free port is expensive and can affect performance
        significantly;
      * there is no use-case for port.
      
      As for remote end (`struct sockaddr *` passed by user), both parts of it
      can be overridden, remote IP and remote port. It's useful if an
      application inside cgroup wants to connect to another application inside
      same cgroup or to itself, but knows nothing about IP assigned to the
      cgroup.
      
      Support is added for IPv4 and IPv6, for TCP and UDP.
      
      IPv4 and IPv6 have separate attach types for same reason as sys_bind
      hooks, i.e. to prevent reading from / writing to e.g. user_ip6 fields
      when user passes sockaddr_in since it'd be out-of-bound.
      
      == Implementation notes ==
      
      The patch introduces new field in `struct proto`: `pre_connect` that is
      a pointer to a function with same signature as `connect` but is called
      before it. The reason is in some cases BPF hooks should be called way
      before control is passed to `sk->sk_prot->connect`. Specifically
      `inet_dgram_connect` autobinds socket before calling
      `sk->sk_prot->connect` and there is no way to call `bpf_bind()` from
      hooks from e.g. `ip4_datagram_connect` or `ip6_datagram_connect` since
      it'd cause double-bind. On the other hand `proto.pre_connect` provides a
      flexible way to add BPF hooks for connect only for necessary `proto` and
      call them at desired time before `connect`. Since `bpf_bind()` is
      allowed to bind only to IP and autobind in `inet_dgram_connect` binds
      only port there is no chance of double-bind.
      
      bpf_bind() sets `force_bind_address_no_port` to bind to only IP despite
      of value of `bind_address_no_port` socket field.
      
      bpf_bind() sets `with_lock` to `false` when calling to __inet_bind()
      and __inet6_bind() since all call-sites, where bpf_bind() is called,
      already hold socket lock.
      Signed-off-by: NAndrey Ignatov <rdna@fb.com>
      Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
      Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
      d74bad4e
    • A
      net: Introduce __inet_bind() and __inet6_bind · 3679d585
      Andrey Ignatov 提交于
      Refactor `bind()` code to make it ready to be called from BPF helper
      function `bpf_bind()` (will be added soon). Implementation of
      `inet_bind()` and `inet6_bind()` is separated into `__inet_bind()` and
      `__inet6_bind()` correspondingly. These function can be used from both
      `sk_prot->bind` and `bpf_bind()` contexts.
      
      New functions have two additional arguments.
      
      `force_bind_address_no_port` forces binding to IP only w/o checking
      `inet_sock.bind_address_no_port` field. It'll allow to bind local end of
      a connection to desired IP in `bpf_bind()` w/o changing
      `bind_address_no_port` field of a socket. It's useful since `bpf_bind()`
      can return an error and we'd need to restore original value of
      `bind_address_no_port` in that case if we changed this before calling to
      the helper.
      
      `with_lock` specifies whether to lock socket when working with `struct
      sk` or not. The argument is set to `true` for `sk_prot->bind`, i.e. old
      behavior is preserved. But it will be set to `false` for `bpf_bind()`
      use-case. The reason is all call-sites, where `bpf_bind()` will be
      called, already hold that socket lock.
      Signed-off-by: NAndrey Ignatov <rdna@fb.com>
      Acked-by: NAlexei Starovoitov <ast@kernel.org>
      Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
      Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
      3679d585
  3. 30 3月, 2018 8 次提交
  4. 29 3月, 2018 8 次提交
  5. 28 3月, 2018 4 次提交
  6. 27 3月, 2018 2 次提交
  7. 24 3月, 2018 6 次提交
  8. 23 3月, 2018 1 次提交