1. 09 12月, 2015 1 次提交
    • T
      net: wrap sock->sk_cgrp_prioidx and ->sk_classid inside a struct · 2a56a1fe
      Tejun Heo 提交于
      Introduce sock->sk_cgrp_data which is a struct sock_cgroup_data.
      ->sk_cgroup_prioidx and ->sk_classid are moved into it.  The struct
      and its accessors are defined in cgroup-defs.h.  This is to prepare
      for overloading the fields with a cgroup pointer.
      
      This patch mostly performs equivalent conversions but the followings
      are noteworthy.
      
      * Equality test before updating classid is removed from
        sock_update_classid().  This shouldn't make any noticeable
        difference and a similar test will be implemented on the helper side
        later.
      
      * sock_update_netprioidx() now takes struct sock_cgroup_data and can
        be moved to netprio_cgroup.h without causing include dependency
        loop.  Moved.
      
      * The dummy version of sock_update_netprioidx() converted to a static
        inline function while at it.
      Signed-off-by: NTejun Heo <tj@kernel.org>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      2a56a1fe
  2. 04 12月, 2015 1 次提交
    • E
      ipv6: kill sk_dst_lock · 6bd4f355
      Eric Dumazet 提交于
      While testing the np->opt RCU conversion, I found that UDP/IPv6 was
      using a mixture of xchg() and sk_dst_lock to protect concurrent changes
      to sk->sk_dst_cache, leading to possible corruptions and crashes.
      
      ip6_sk_dst_lookup_flow() uses sk_dst_check() anyway, so the simplest
      way to fix the mess is to remove sk_dst_lock completely, as we did for
      IPv4.
      
      __ip6_dst_store() and ip6_dst_store() share same implementation.
      
      sk_setup_caps() being called with socket lock being held or not,
      we have to use sk_dst_set() instead of __sk_dst_set()
      
      Note that I had to move the "np->dst_cookie = rt6_get_cookie(rt);"
      in ip6_dst_store() before the sk_setup_caps(sk, dst) call.
      
      This is because ip6_dst_store() can be called from process context,
      without any lock held.
      
      As soon as the dst is installed in sk->sk_dst_cache, dst can be freed
      from another cpu doing a concurrent ip6_dst_store()
      
      Doing the dst dereference before doing the install is needed to make
      sure no use after free would trigger.
      Signed-off-by: NEric Dumazet <edumazet@google.com>
      Reported-by: NDmitry Vyukov <dvyukov@google.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      6bd4f355
  3. 02 12月, 2015 1 次提交
    • E
      net: rename SOCK_ASYNC_NOSPACE and SOCK_ASYNC_WAITDATA · 9cd3e072
      Eric Dumazet 提交于
      This patch is a cleanup to make following patch easier to
      review.
      
      Goal is to move SOCK_ASYNC_NOSPACE and SOCK_ASYNC_WAITDATA
      from (struct socket)->flags to a (struct socket_wq)->flags
      to benefit from RCU protection in sock_wake_async()
      
      To ease backports, we rename both constants.
      
      Two new helpers, sk_set_bit(int nr, struct sock *sk)
      and sk_clear_bit(int net, struct sock *sk) are added so that
      following patch can change their implementation.
      Signed-off-by: NEric Dumazet <edumazet@google.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      9cd3e072
  4. 01 12月, 2015 1 次提交
  5. 07 11月, 2015 1 次提交
    • M
      mm, page_alloc: distinguish between being unable to sleep, unwilling to sleep... · d0164adc
      Mel Gorman 提交于
      mm, page_alloc: distinguish between being unable to sleep, unwilling to sleep and avoiding waking kswapd
      
      __GFP_WAIT has been used to identify atomic context in callers that hold
      spinlocks or are in interrupts.  They are expected to be high priority and
      have access one of two watermarks lower than "min" which can be referred
      to as the "atomic reserve".  __GFP_HIGH users get access to the first
      lower watermark and can be called the "high priority reserve".
      
      Over time, callers had a requirement to not block when fallback options
      were available.  Some have abused __GFP_WAIT leading to a situation where
      an optimisitic allocation with a fallback option can access atomic
      reserves.
      
      This patch uses __GFP_ATOMIC to identify callers that are truely atomic,
      cannot sleep and have no alternative.  High priority users continue to use
      __GFP_HIGH.  __GFP_DIRECT_RECLAIM identifies callers that can sleep and
      are willing to enter direct reclaim.  __GFP_KSWAPD_RECLAIM to identify
      callers that want to wake kswapd for background reclaim.  __GFP_WAIT is
      redefined as a caller that is willing to enter direct reclaim and wake
      kswapd for background reclaim.
      
      This patch then converts a number of sites
      
      o __GFP_ATOMIC is used by callers that are high priority and have memory
        pools for those requests. GFP_ATOMIC uses this flag.
      
      o Callers that have a limited mempool to guarantee forward progress clear
        __GFP_DIRECT_RECLAIM but keep __GFP_KSWAPD_RECLAIM. bio allocations fall
        into this category where kswapd will still be woken but atomic reserves
        are not used as there is a one-entry mempool to guarantee progress.
      
      o Callers that are checking if they are non-blocking should use the
        helper gfpflags_allow_blocking() where possible. This is because
        checking for __GFP_WAIT as was done historically now can trigger false
        positives. Some exceptions like dm-crypt.c exist where the code intent
        is clearer if __GFP_DIRECT_RECLAIM is used instead of the helper due to
        flag manipulations.
      
      o Callers that built their own GFP flags instead of starting with GFP_KERNEL
        and friends now also need to specify __GFP_KSWAPD_RECLAIM.
      
      The first key hazard to watch out for is callers that removed __GFP_WAIT
      and was depending on access to atomic reserves for inconspicuous reasons.
      In some cases it may be appropriate for them to use __GFP_HIGH.
      
      The second key hazard is callers that assembled their own combination of
      GFP flags instead of starting with something like GFP_KERNEL.  They may
      now wish to specify __GFP_KSWAPD_RECLAIM.  It's almost certainly harmless
      if it's missed in most cases as other activity will wake kswapd.
      Signed-off-by: NMel Gorman <mgorman@techsingularity.net>
      Acked-by: NVlastimil Babka <vbabka@suse.cz>
      Acked-by: NMichal Hocko <mhocko@suse.com>
      Acked-by: NJohannes Weiner <hannes@cmpxchg.org>
      Cc: Christoph Lameter <cl@linux.com>
      Cc: David Rientjes <rientjes@google.com>
      Cc: Vitaly Wool <vitalywool@gmail.com>
      Cc: Rik van Riel <riel@redhat.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      d0164adc
  6. 03 11月, 2015 1 次提交
  7. 28 10月, 2015 1 次提交
  8. 13 10月, 2015 2 次提交
    • E
      net: SO_INCOMING_CPU setsockopt() support · 70da268b
      Eric Dumazet 提交于
      SO_INCOMING_CPU as added in commit 2c8c56e1 was a getsockopt() command
      to fetch incoming cpu handling a particular TCP flow after accept()
      
      This commits adds setsockopt() support and extends SO_REUSEPORT selection
      logic : If a TCP listener or UDP socket has this option set, a packet is
      delivered to this socket only if CPU handling the packet matches the specified
      one.
      
      This allows to build very efficient TCP servers, using one listener per
      RX queue, as the associated TCP listener should only accept flows handled
      in softirq by the same cpu.
      This provides optimal NUMA behavior and keep cpu caches hot.
      
      Note that __inet_lookup_listener() still has to iterate over the list of
      all listeners. Following patch puts sk_refcnt in a different cache line
      to let this iteration hit only shared and read mostly cache lines.
      Signed-off-by: NEric Dumazet <edumazet@google.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      70da268b
    • E
      sock: support per-packet fwmark · f28ea365
      Edward Jee 提交于
      It's useful to allow users to set fwmark for an individual packet,
      without changing the socket state. The function this patch adds in
      sock layer can be used by the protocols that need such a feature.
      Signed-off-by: NEdward Hyunkoo Jee <edjee@google.com>
      Signed-off-by: NEric Dumazet <edumazet@google.com>
      Cc: Willem de Bruijn <willemb@google.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      f28ea365
  9. 04 10月, 2015 1 次提交
    • E
      tcp/dccp: add SLAB_DESTROY_BY_RCU flag for request sockets · e96f78ab
      Eric Dumazet 提交于
      Before letting request sockets being put in TCP/DCCP regular
      ehash table, we need to add either :
      
      - SLAB_DESTROY_BY_RCU flag to their kmem_cache
      - add RCU grace period before freeing them.
      
      Since we carefully respected the SLAB_DESTROY_BY_RCU protocol
      like ESTABLISH and TIMEWAIT sockets, use it here.
      
      req_prot_init() being only used by TCP and DCCP, I did not add
      a new slab_flags into their rsk_prot, but reuse prot->slab_flags
      
      Since all reqsk_alloc() users are correctly dealing with a failure,
      add the __GFP_NOWARN flag to avoid traces under pressure.
      
      Fixes: 079096f1 ("tcp/dccp: install syn_recv requests into ehash table")
      Signed-off-by: NEric Dumazet <edumazet@google.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      e96f78ab
  10. 16 9月, 2015 1 次提交
  11. 28 8月, 2015 1 次提交
  12. 31 7月, 2015 1 次提交
  13. 27 7月, 2015 1 次提交
  14. 01 7月, 2015 1 次提交
    • C
      sock_diag: don't broadcast kernel sockets · b922622e
      Craig Gallek 提交于
      Kernel sockets do not hold a reference for the network namespace to
      which they point.  Socket destruction broadcasting relies on the
      network namespace and will cause the splat below when a kernel socket
      is destroyed.
      
      This fix simply ignores kernel sockets when they are destroyed.
      
      Reported as:
      general protection fault: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
      CPU: 1 PID: 9130 Comm: kworker/1:1 Not tainted 4.1.0-gelk-debug+ #1
      Workqueue: sock_diag_events sock_diag_broadcast_destroy_work
      Stack:
       ffff8800b9c586c0 ffff8800b9c586c0 ffff8800ac4692c0 ffff8800936d4a90
       ffff8800352efd38 ffffffff8469a93e ffff8800352efd98 ffffffffc09b9b90
       ffff8800352efd78 ffff8800ac4692c0 ffff8800b9c586c0 ffff8800831b6ab8
      Call Trace:
       [<ffffffff8469a93e>] ? mutex_unlock+0xe/0x10
       [<ffffffffc09b9b90>] ? inet_diag_handler_get_info+0x110/0x1fb [inet_diag]
       [<ffffffff845c868d>] netlink_broadcast+0x1d/0x20
       [<ffffffff8469a93e>] ? mutex_unlock+0xe/0x10
       [<ffffffff845b2bf5>] sock_diag_broadcast_destroy_work+0xd5/0x160
       [<ffffffff8408ea97>] process_one_work+0x147/0x420
       [<ffffffff8408f0f9>] worker_thread+0x69/0x470
       [<ffffffff8409fda3>] ? preempt_count_sub+0xa3/0xf0
       [<ffffffff8408f090>] ? rescuer_thread+0x320/0x320
       [<ffffffff84093cd7>] kthread+0x107/0x120
       [<ffffffff84093bd0>] ? kthread_create_on_node+0x1b0/0x1b0
       [<ffffffff8469d31f>] ret_from_fork+0x3f/0x70
       [<ffffffff84093bd0>] ? kthread_create_on_node+0x1b0/0x1b0
      
      Tested:
        Using a debug kernel while 'ss -E' is running:
        ip netns add test-ns
        ip netns delete test-ns
      
      Fixes: eb4cb008 sock_diag: define destruction multicast groups
      Fixes: 26abe143 net: Modify sk_alloc to not reference count the
        netns of kernel sockets.
      Reported-by: NDave Jones <davej@codemonkey.org.uk>
      Suggested-by: NEric Dumazet <eric.dumazet@gmail.com>
      Signed-off-by: NCraig Gallek <kraig@google.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      b922622e
  15. 29 6月, 2015 1 次提交
  16. 16 6月, 2015 1 次提交
  17. 12 6月, 2015 1 次提交
    • S
      net: don't wait for order-3 page allocation · fb05e7a8
      Shaohua Li 提交于
      We saw excessive direct memory compaction triggered by skb_page_frag_refill.
      This causes performance issues and add latency. Commit 5640f768
      introduces the order-3 allocation. According to the changelog, the order-3
      allocation isn't a must-have but to improve performance. But direct memory
      compaction has high overhead. The benefit of order-3 allocation can't
      compensate the overhead of direct memory compaction.
      
      This patch makes the order-3 page allocation atomic. If there is no memory
      pressure and memory isn't fragmented, the alloction will still success, so we
      don't sacrifice the order-3 benefit here. If the atomic allocation fails,
      direct memory compaction will not be triggered, skb_page_frag_refill will
      fallback to order-0 immediately, hence the direct memory compaction overhead is
      avoided. In the allocation failure case, kswapd is waken up and doing
      compaction, so chances are allocation could success next time.
      
      alloc_skb_with_frags is the same.
      
      The mellanox driver does similar thing, if this is accepted, we must fix
      the driver too.
      
      V3: fix the same issue in alloc_skb_with_frags as pointed out by Eric
      V2: make the changelog clearer
      
      Cc: Eric Dumazet <edumazet@google.com>
      Cc: Chris Mason <clm@fb.com>
      Cc: Debabrata Banerjee <dbavatar@gmail.com>
      Signed-off-by: NShaohua Li <shli@fb.com>
      Acked-by: NEric Dumazet <edumazet@google.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      fb05e7a8
  18. 11 6月, 2015 1 次提交
    • M
      net, swap: Remove a warning and clarify why sk_mem_reclaim is required when deactivating swap · 5d753610
      Mel Gorman 提交于
      Jeff Layton reported the following;
      
       [   74.232485] ------------[ cut here ]------------
       [   74.233354] WARNING: CPU: 2 PID: 754 at net/core/sock.c:364 sk_clear_memalloc+0x51/0x80()
       [   74.234790] Modules linked in: cts rpcsec_gss_krb5 nfsv4 dns_resolver nfs fscache xfs libcrc32c snd_hda_codec_generic snd_hda_intel snd_hda_controller snd_hda_codec snd_hda_core snd_hwdep snd_seq snd_seq_device nfsd snd_pcm snd_timer snd e1000 ppdev parport_pc joydev parport pvpanic soundcore floppy serio_raw i2c_piix4 pcspkr nfs_acl lockd virtio_balloon acpi_cpufreq auth_rpcgss grace sunrpc qxl drm_kms_helper ttm drm virtio_console virtio_blk virtio_pci ata_generic virtio_ring pata_acpi virtio
       [   74.243599] CPU: 2 PID: 754 Comm: swapoff Not tainted 4.1.0-rc6+ #5
       [   74.244635] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
       [   74.245546]  0000000000000000 0000000079e69e31 ffff8800d066bde8 ffffffff8179263d
       [   74.246786]  0000000000000000 0000000000000000 ffff8800d066be28 ffffffff8109e6fa
       [   74.248175]  0000000000000000 ffff880118d48000 ffff8800d58f5c08 ffff880036e380a8
       [   74.249483] Call Trace:
       [   74.249872]  [<ffffffff8179263d>] dump_stack+0x45/0x57
       [   74.250703]  [<ffffffff8109e6fa>] warn_slowpath_common+0x8a/0xc0
       [   74.251655]  [<ffffffff8109e82a>] warn_slowpath_null+0x1a/0x20
       [   74.252585]  [<ffffffff81661241>] sk_clear_memalloc+0x51/0x80
       [   74.253519]  [<ffffffffa0116c72>] xs_disable_swap+0x42/0x80 [sunrpc]
       [   74.254537]  [<ffffffffa01109de>] rpc_clnt_swap_deactivate+0x7e/0xc0 [sunrpc]
       [   74.255610]  [<ffffffffa03e4fd7>] nfs_swap_deactivate+0x27/0x30 [nfs]
       [   74.256582]  [<ffffffff811e99d4>] destroy_swap_extents+0x74/0x80
       [   74.257496]  [<ffffffff811ecb52>] SyS_swapoff+0x222/0x5c0
       [   74.258318]  [<ffffffff81023f27>] ? syscall_trace_leave+0xc7/0x140
       [   74.259253]  [<ffffffff81798dae>] system_call_fastpath+0x12/0x71
       [   74.260158] ---[ end trace 2530722966429f10 ]---
      
      The warning in question was unnecessary but with Jeff's series the rules
      are also clearer.  This patch removes the warning and updates the comment
      to explain why sk_mem_reclaim() may still be called.
      
      [jlayton: remove if (sk->sk_forward_alloc) conditional. As Leon
                points out that it's not needed.]
      
      Cc: Leon Romanovsky <leon@leon.nu>
      Signed-off-by: NMel Gorman <mgorman@suse.de>
      Signed-off-by: NJeff Layton <jeff.layton@primarydata.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      5d753610
  19. 27 5月, 2015 1 次提交
  20. 18 5月, 2015 1 次提交
  21. 11 5月, 2015 3 次提交
  22. 04 5月, 2015 1 次提交
  23. 13 4月, 2015 1 次提交
  24. 07 4月, 2015 1 次提交
    • H
      ipv6: protect skb->sk accesses from recursive dereference inside the stack · f60e5990
      hannes@stressinduktion.org 提交于
      We should not consult skb->sk for output decisions in xmit recursion
      levels > 0 in the stack. Otherwise local socket settings could influence
      the result of e.g. tunnel encapsulation process.
      
      ipv6 does not conform with this in three places:
      
      1) ip6_fragment: we do consult ipv6_npinfo for frag_size
      
      2) sk_mc_loop in ipv6 uses skb->sk and checks if we should
         loop the packet back to the local socket
      
      3) ip6_skb_dst_mtu could query the settings from the user socket and
         force a wrong MTU
      
      Furthermore:
      In sk_mc_loop we could potentially land in WARN_ON(1) if we use a
      PF_PACKET socket ontop of an IPv6-backed vxlan device.
      
      Reuse xmit_recursion as we are currently only interested in protecting
      tunnel devices.
      
      Cc: Jiri Pirko <jiri@resnulli.us>
      Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      f60e5990
  25. 24 3月, 2015 1 次提交
  26. 21 3月, 2015 1 次提交
    • E
      inet: get rid of central tcp/dccp listener timer · fa76ce73
      Eric Dumazet 提交于
      One of the major issue for TCP is the SYNACK rtx handling,
      done by inet_csk_reqsk_queue_prune(), fired by the keepalive
      timer of a TCP_LISTEN socket.
      
      This function runs for awful long times, with socket lock held,
      meaning that other cpus needing this lock have to spin for hundred of ms.
      
      SYNACK are sent in huge bursts, likely to cause severe drops anyway.
      
      This model was OK 15 years ago when memory was very tight.
      
      We now can afford to have a timer per request sock.
      
      Timer invocations no longer need to lock the listener,
      and can be run from all cpus in parallel.
      
      With following patch increasing somaxconn width to 32 bits,
      I tested a listener with more than 4 million active request sockets,
      and a steady SYNFLOOD of ~200,000 SYN per second.
      Host was sending ~830,000 SYNACK per second.
      
      This is ~100 times more what we could achieve before this patch.
      
      Later, we will get rid of the listener hash and use ehash instead.
      Signed-off-by: NEric Dumazet <edumazet@google.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      fa76ce73
  27. 17 3月, 2015 2 次提交
  28. 13 3月, 2015 3 次提交
  29. 12 3月, 2015 1 次提交
    • E
      net: add real socket cookies · 33cf7c90
      Eric Dumazet 提交于
      A long standing problem in netlink socket dumps is the use
      of kernel socket addresses as cookies.
      
      1) It is a security concern.
      
      2) Sockets can be reused quite quickly, so there is
         no guarantee a cookie is used once and identify
         a flow.
      
      3) request sock, establish sock, and timewait socks
         for a given flow have different cookies.
      
      Part of our effort to bring better TCP statistics requires
      to switch to a different allocator.
      
      In this patch, I chose to use a per network namespace 64bit generator,
      and to use it only in the case a socket needs to be dumped to netlink.
      (This might be refined later if needed)
      
      Note that I tried to carry cookies from request sock, to establish sock,
      then timewait sockets.
      Signed-off-by: NEric Dumazet <edumazet@google.com>
      Cc: Eric Salo <salo@google.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      33cf7c90
  30. 11 3月, 2015 1 次提交
  31. 03 3月, 2015 1 次提交
  32. 02 3月, 2015 1 次提交
  33. 03 2月, 2015 1 次提交
    • W
      net-timestamp: no-payload only sysctl · b245be1f
      Willem de Bruijn 提交于
      Tx timestamps are looped onto the error queue on top of an skb. This
      mechanism leaks packet headers to processes unless the no-payload
      options SOF_TIMESTAMPING_OPT_TSONLY is set.
      
      Add a sysctl that optionally drops looped timestamp with data. This
      only affects processes without CAP_NET_RAW.
      
      The policy is checked when timestamps are generated in the stack.
      It is possible for timestamps with data to be reported after the
      sysctl is set, if these were queued internally earlier.
      
      No vulnerability is immediately known that exploits knowledge
      gleaned from packet headers, but it may still be preferable to allow
      administrators to lock down this path at the cost of possible
      breakage of legacy applications.
      Signed-off-by: NWillem de Bruijn <willemb@google.com>
      
      ----
      
      Changes
        (v1 -> v2)
        - test socket CAP_NET_RAW instead of capable(CAP_NET_RAW)
        (rfc -> v1)
        - document the sysctl in Documentation/sysctl/net.txt
        - fix access control race: read .._OPT_TSONLY only once,
              use same value for permission check and skb generation.
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      b245be1f
  34. 06 12月, 2014 1 次提交
    • A
      net: sock: allow eBPF programs to be attached to sockets · 89aa0758
      Alexei Starovoitov 提交于
      introduce new setsockopt() command:
      
      setsockopt(sock, SOL_SOCKET, SO_ATTACH_BPF, &prog_fd, sizeof(prog_fd))
      
      where prog_fd was received from syscall bpf(BPF_PROG_LOAD, attr, ...)
      and attr->prog_type == BPF_PROG_TYPE_SOCKET_FILTER
      
      setsockopt() calls bpf_prog_get() which increments refcnt of the program,
      so it doesn't get unloaded while socket is using the program.
      
      The same eBPF program can be attached to multiple sockets.
      
      User task exit automatically closes socket which calls sk_filter_uncharge()
      which decrements refcnt of eBPF program
      Signed-off-by: NAlexei Starovoitov <ast@plumgrid.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      89aa0758