1. 22 3月, 2019 1 次提交
    • G
      net: kernel hookers service for toa module · eff26a80
      George Zhang 提交于
      LVS fullnat will replace network traffic's source ip with its local ip,
      and thus the backend servers cannot obtain the real client ip.
      
      To solve this, LVS has introduced the tcp option address (TOA) to store
      the essential ip address information in the last tcp ack packet of the
      3-way handshake, and the backend servers need to retrieve it from the
      packet header.
      
      In this patch, we have introduced the sk_toa_data member in the sock
      structure to hold the TOA information. There used to be an in-tree
      module for TOA managing, whereas it has now been maintained as an
      standalone module.
      
      In this case, the toa module should register its hook function(s) using
      the provided interfaces in the hookers module.
      
      TOA in sock structure:
      
      	__be32 sk_toa_data[16];
      
      The hookers module only provides the sk_toa_data placeholder, and the
      toa module can use this variable through the layout it needs.
      
      Hook interfaces:
      
      The hookers module replaces the kernel's syn_recv_sock and getname
      handler with a stub that chains the toa module's hook function(s) to the
      original handling function. The hookers module allows hook functions to
      be installed and uninstalled in any order.
      
      toa module:
      
      The external toa module will be provided in separate RPM package.
      
      [xuyu@linux.alibaba.com: amend commit log]
      Signed-off-by: NGeorge Zhang <georgezhang@linux.alibaba.com>
      Signed-off-by: NXu Yu <xuyu@linux.alibaba.com>
      Reviewed-by: NCaspar Zhang <caspar@linux.alibaba.com>
      eff26a80
  2. 25 7月, 2018 1 次提交
  3. 29 5月, 2018 1 次提交
    • S
      net: Introduce generic failover module · 30c8bd5a
      Sridhar Samudrala 提交于
      The failover module provides a generic interface for paravirtual drivers
      to register a netdev and a set of ops with a failover instance. The ops
      are used as event handlers that get called to handle netdev register/
      unregister/link change/name change events on slave pci ethernet devices
      with the same mac address as the failover netdev.
      
      This enables paravirtual drivers to use a VF as an accelerated low latency
      datapath. It also allows migration of VMs with direct attached VFs by
      failing over to the paravirtual datapath when the VF is unplugged.
      Signed-off-by: NSridhar Samudrala <sridhar.samudrala@intel.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      30c8bd5a
  4. 24 5月, 2018 1 次提交
    • A
      net: add skeleton of bpfilter kernel module · d2ba09c1
      Alexei Starovoitov 提交于
      bpfilter.ko consists of bpfilter_kern.c (normal kernel module code)
      and user mode helper code that is embedded into bpfilter.ko
      
      The steps to build bpfilter.ko are the following:
      - main.c is compiled by HOSTCC into the bpfilter_umh elf executable file
      - with quite a bit of objcopy and Makefile magic the bpfilter_umh elf file
        is converted into bpfilter_umh.o object file
        with _binary_net_bpfilter_bpfilter_umh_start and _end symbols
        Example:
        $ nm ./bld_x64/net/bpfilter/bpfilter_umh.o
        0000000000004cf8 T _binary_net_bpfilter_bpfilter_umh_end
        0000000000004cf8 A _binary_net_bpfilter_bpfilter_umh_size
        0000000000000000 T _binary_net_bpfilter_bpfilter_umh_start
      - bpfilter_umh.o and bpfilter_kern.o are linked together into bpfilter.ko
      
      bpfilter_kern.c is a normal kernel module code that calls
      the fork_usermode_blob() helper to execute part of its own data
      as a user mode process.
      
      Notice that _binary_net_bpfilter_bpfilter_umh_start - end
      is placed into .init.rodata section, so it's freed as soon as __init
      function of bpfilter.ko is finished.
      As part of __init the bpfilter.ko does first request/reply action
      via two unix pipe provided by fork_usermode_blob() helper to
      make sure that umh is healthy. If not it will kill it via pid.
      
      Later bpfilter_process_sockopt() will be called from bpfilter hooks
      in get/setsockopt() to pass iptable commands into umh via bpfilter.ko
      
      If admin does 'rmmod bpfilter' the __exit code bpfilter.ko will
      kill umh as well.
      Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      d2ba09c1
  5. 04 5月, 2018 1 次提交
  6. 01 5月, 2018 1 次提交
  7. 17 4月, 2018 1 次提交
    • J
      page_pool: refurbish version of page_pool code · ff7d6b27
      Jesper Dangaard Brouer 提交于
      Need a fast page recycle mechanism for ndo_xdp_xmit API for returning
      pages on DMA-TX completion time, which have good cross CPU
      performance, given DMA-TX completion time can happen on a remote CPU.
      
      Refurbish my page_pool code, that was presented[1] at MM-summit 2016.
      Adapted page_pool code to not depend the page allocator and
      integration into struct page.  The DMA mapping feature is kept,
      even-though it will not be activated/used in this patchset.
      
      [1] http://people.netfilter.org/hawk/presentations/MM-summit2016/generic_page_pool_mm_summit2016.pdf
      
      V2: Adjustments requested by Tariq
       - Changed page_pool_create return codes, don't return NULL, only
         ERR_PTR, as this simplifies err handling in drivers.
      
      V4: many small improvements and cleanups
      - Add DOC comment section, that can be used by kernel-doc
      - Improve fallback mode, to work better with refcnt based recycling
        e.g. remove a WARN as pointed out by Tariq
        e.g. quicker fallback if ptr_ring is empty.
      
      V5: Fixed SPDX license as pointed out by Alexei
      
      V6: Adjustments requested by Eric Dumazet
       - Adjust ____cacheline_aligned_in_smp usage/placement
       - Move rcu_head in struct page_pool
       - Free pages quicker on destroy, minimize resources delayed an RCU period
       - Remove code for forward/backward compat ABI interface
      
      V8: Issues found by kbuild test robot
       - Address sparse should be static warnings
       - Only compile+link when a driver use/select page_pool,
         mlx5 selects CONFIG_PAGE_POOL, although its first used in two patches
      Signed-off-by: NJesper Dangaard Brouer <brouer@redhat.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      ff7d6b27
  8. 09 1月, 2018 1 次提交
  9. 03 1月, 2018 1 次提交
  10. 28 11月, 2017 1 次提交
  11. 04 9月, 2017 1 次提交
  12. 30 8月, 2017 1 次提交
    • J
      nsh: add GSO support · c411ed85
      Jiri Benc 提交于
      Add a new nsh/ directory. It currently holds only GSO functions but more
      will come: in particular, code shared by openvswitch and tc to manipulate
      NSH headers.
      
      For now, assume there's no hardware support for NSH segmentation. We can
      always introduce netdev->nsh_features later.
      Signed-off-by: NJiri Benc <jbenc@redhat.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      c411ed85
  13. 29 8月, 2017 2 次提交
  14. 16 6月, 2017 1 次提交
  15. 18 2月, 2017 1 次提交
    • D
      bpf: make jited programs visible in traces · 74451e66
      Daniel Borkmann 提交于
      Long standing issue with JITed programs is that stack traces from
      function tracing check whether a given address is kernel code
      through {__,}kernel_text_address(), which checks for code in core
      kernel, modules and dynamically allocated ftrace trampolines. But
      what is still missing is BPF JITed programs (interpreted programs
      are not an issue as __bpf_prog_run() will be attributed to them),
      thus when a stack trace is triggered, the code walking the stack
      won't see any of the JITed ones. The same for address correlation
      done from user space via reading /proc/kallsyms. This is read by
      tools like perf, but the latter is also useful for permanent live
      tracing with eBPF itself in combination with stack maps when other
      eBPF types are part of the callchain. See offwaketime example on
      dumping stack from a map.
      
      This work tries to tackle that issue by making the addresses and
      symbols known to the kernel. The lookup from *kernel_text_address()
      is implemented through a latched RB tree that can be read under
      RCU in fast-path that is also shared for symbol/size/offset lookup
      for a specific given address in kallsyms. The slow-path iteration
      through all symbols in the seq file done via RCU list, which holds
      a tiny fraction of all exported ksyms, usually below 0.1 percent.
      Function symbols are exported as bpf_prog_<tag>, in order to aide
      debugging and attribution. This facility is currently enabled for
      root-only when bpf_jit_kallsyms is set to 1, and disabled if hardening
      is active in any mode. The rationale behind this is that still a lot
      of systems ship with world read permissions on kallsyms thus addresses
      should not get suddenly exposed for them. If that situation gets
      much better in future, we always have the option to change the
      default on this. Likewise, unprivileged programs are not allowed
      to add entries there either, but that is less of a concern as most
      such programs types relevant in this context are for root-only anyway.
      If enabled, call graphs and stack traces will then show a correct
      attribution; one example is illustrated below, where the trace is
      now visible in tooling such as perf script --kallsyms=/proc/kallsyms
      and friends.
      
      Before:
      
        7fff8166889d bpf_clone_redirect+0x80007f0020ed (/lib/modules/4.9.0-rc8+/build/vmlinux)
               f5d80 __sendmsg_nocancel+0xffff006451f1a007 (/usr/lib64/libc-2.18.so)
      
      After:
      
        7fff816688b7 bpf_clone_redirect+0x80007f002107 (/lib/modules/4.9.0-rc8+/build/vmlinux)
        7fffa0575728 bpf_prog_33c45a467c9e061a+0x8000600020fb (/lib/modules/4.9.0-rc8+/build/vmlinux)
        7fffa07ef1fc cls_bpf_classify+0x8000600020dc (/lib/modules/4.9.0-rc8+/build/vmlinux)
        7fff81678b68 tc_classify+0x80007f002078 (/lib/modules/4.9.0-rc8+/build/vmlinux)
        7fff8164d40b __netif_receive_skb_core+0x80007f0025fb (/lib/modules/4.9.0-rc8+/build/vmlinux)
        7fff8164d718 __netif_receive_skb+0x80007f002018 (/lib/modules/4.9.0-rc8+/build/vmlinux)
        7fff8164e565 process_backlog+0x80007f002095 (/lib/modules/4.9.0-rc8+/build/vmlinux)
        7fff8164dc71 net_rx_action+0x80007f002231 (/lib/modules/4.9.0-rc8+/build/vmlinux)
        7fff81767461 __softirqentry_text_start+0x80007f0020d1 (/lib/modules/4.9.0-rc8+/build/vmlinux)
        7fff817658ac do_softirq_own_stack+0x80007f00201c (/lib/modules/4.9.0-rc8+/build/vmlinux)
        7fff810a2c20 do_softirq+0x80007f002050 (/lib/modules/4.9.0-rc8+/build/vmlinux)
        7fff810a2cb5 __local_bh_enable_ip+0x80007f002085 (/lib/modules/4.9.0-rc8+/build/vmlinux)
        7fff8168d452 ip_finish_output2+0x80007f002152 (/lib/modules/4.9.0-rc8+/build/vmlinux)
        7fff8168ea3d ip_finish_output+0x80007f00217d (/lib/modules/4.9.0-rc8+/build/vmlinux)
        7fff8168f2af ip_output+0x80007f00203f (/lib/modules/4.9.0-rc8+/build/vmlinux)
        [...]
        7fff81005854 do_syscall_64+0x80007f002054 (/lib/modules/4.9.0-rc8+/build/vmlinux)
        7fff817649eb return_from_SYSCALL_64+0x80007f002000 (/lib/modules/4.9.0-rc8+/build/vmlinux)
               f5d80 __sendmsg_nocancel+0xffff01c484812007 (/usr/lib64/libc-2.18.so)
      Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
      Acked-by: NAlexei Starovoitov <ast@kernel.org>
      Cc: linux-kernel@vger.kernel.org
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      74451e66
  16. 09 2月, 2017 1 次提交
  17. 04 2月, 2017 1 次提交
  18. 25 1月, 2017 1 次提交
    • Y
      net: Introduce psample, a new genetlink channel for packet sampling · 6ae0a628
      Yotam Gigi 提交于
      Add a general way for kernel modules to sample packets, without being tied
      to any specific subsystem. This netlink channel can be used by tc,
      iptables, etc. and allow to standardize packet sampling in the kernel.
      
      For every sampled packet, the psample module adds the following metadata
      fields:
      
      PSAMPLE_ATTR_IIFINDEX - the packets input ifindex, if applicable
      
      PSAMPLE_ATTR_OIFINDEX - the packet output ifindex, if applicable
      
      PSAMPLE_ATTR_ORIGSIZE - the packet's original size, in case it has been
         truncated during sampling
      
      PSAMPLE_ATTR_SAMPLE_GROUP - the packet's sample group, which is set by the
         user who initiated the sampling. This field allows the user to
         differentiate between several samplers working simultaneously and
         filter packets relevant to him
      
      PSAMPLE_ATTR_GROUP_SEQ - sequence counter of last sent packet. The
         sequence is kept for each group
      
      PSAMPLE_ATTR_SAMPLE_RATE - the sampling rate used for sampling the packets
      
      PSAMPLE_ATTR_DATA - the actual packet bits
      
      The sampled packets are sent to the PSAMPLE_NL_MCGRP_SAMPLE multicast
      group. In addition, add the GET_GROUPS netlink command which allows the
      user to see the current sample groups, their refcount and sequence number.
      This command currently supports only netlink dump mode.
      Signed-off-by: NYotam Gigi <yotamg@mellanox.com>
      Signed-off-by: NJiri Pirko <jiri@mellanox.com>
      Reviewed-by: NJamal Hadi Salim <jhs@mojatatu.com>
      Reviewed-by: NSimon Horman <simon.horman@netronome.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      6ae0a628
  19. 11 1月, 2017 1 次提交
    • A
      cgroup: move CONFIG_SOCK_CGROUP_DATA to init/Kconfig · 73b35147
      Arnd Bergmann 提交于
      We now 'select SOCK_CGROUP_DATA' but Kconfig complains that this is
      not right when CONFIG_NET is disabled and there is no socket interface:
      
      warning: (CGROUP_BPF) selects SOCK_CGROUP_DATA which has unmet direct dependencies (NET)
      
      I don't know what the correct solution for this is, but simply removing
      the dependency on NET from SOCK_CGROUP_DATA by moving it out of the
      'if NET' section avoids the warning and does not produce other build
      errors.
      
      Fixes: 483c4933 ("cgroup: Fix CGROUP_BPF config")
      Signed-off-by: NArnd Bergmann <arnd@arndb.de>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      73b35147
  20. 10 1月, 2017 1 次提交
  21. 02 12月, 2016 1 次提交
    • T
      bpf: BPF for lightweight tunnel infrastructure · 3a0af8fd
      Thomas Graf 提交于
      Registers new BPF program types which correspond to the LWT hooks:
        - BPF_PROG_TYPE_LWT_IN   => dst_input()
        - BPF_PROG_TYPE_LWT_OUT  => dst_output()
        - BPF_PROG_TYPE_LWT_XMIT => lwtunnel_xmit()
      
      The separate program types are required to differentiate between the
      capabilities each LWT hook allows:
      
       * Programs attached to dst_input() or dst_output() are restricted and
         may only read the data of an skb. This prevent modification and
         possible invalidation of already validated packet headers on receive
         and the construction of illegal headers while the IP headers are
         still being assembled.
      
       * Programs attached to lwtunnel_xmit() are allowed to modify packet
         content as well as prepending an L2 header via a newly introduced
         helper bpf_skb_change_head(). This is safe as lwtunnel_xmit() is
         invoked after the IP header has been assembled completely.
      
      All BPF programs receive an skb with L3 headers attached and may return
      one of the following error codes:
      
       BPF_OK - Continue routing as per nexthop
       BPF_DROP - Drop skb and return EPERM
       BPF_REDIRECT - Redirect skb to device as per redirect() helper.
                      (Only valid in lwtunnel_xmit() context)
      
      The return codes are binary compatible with their TC_ACT_
      relatives to ease compatibility.
      Signed-off-by: NThomas Graf <tgraf@suug.ch>
      Acked-by: NAlexei Starovoitov <ast@kernel.org>
      Acked-by: NDaniel Borkmann <daniel@iogearbox.net>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      3a0af8fd
  22. 18 8月, 2016 1 次提交
    • T
      strparser: Stream parser for messages · 43a0c675
      Tom Herbert 提交于
      This patch introduces a utility for parsing application layer protocol
      messages in a TCP stream. This is a generalization of the mechanism
      implemented of Kernel Connection Multiplexor.
      
      The API includes a context structure, a set of callbacks, utility
      functions, and a data ready function.
      
      A stream parser instance is defined by a strparse structure that
      is bound to a TCP socket. The function to initialize the structure
      is:
      
      int strp_init(struct strparser *strp, struct sock *csk,
                    struct strp_callbacks *cb);
      
      csk is the TCP socket being bound to and cb are the parser callbacks.
      
      The upper layer calls strp_tcp_data_ready when data is ready on the lower
      socket for strparser to process. This should be called from a data_ready
      callback that is set on the socket:
      
      void strp_tcp_data_ready(struct strparser *strp);
      
      A parser is bound to a TCP socket by setting data_ready function to
      strp_tcp_data_ready so that all receive indications on the socket
      go through the parser. This is assumes that sk_user_data is set to
      the strparser structure.
      
      There are four callbacks.
       - parse_msg is called to parse the message (returns length or error).
       - rcv_msg is called when a complete message has been received
       - read_sock_done is called when data_ready function exits
       - abort_parser is called to abort the parser
      
      The input to parse_msg is an skbuff which contains next message under
      construction. The backend processing of parse_msg will parse the
      application layer protocol headers to determine the length of
      the message in the stream. The possible return values are:
      
         >0 : indicates length of successfully parsed message
         0  : indicates more data must be received to parse the message
         -ESTRPIPE : current message should not be processed by the
            kernel, return control of the socket to userspace which
            can proceed to read the messages itself
         other < 0 : Error is parsing, give control back to userspace
            assuming that synchronzation is lost and the stream
            is unrecoverable (application expected to close TCP socket)
      
      In the case of error return (< 0) strparse will stop the parser
      and report and error to userspace. The application must deal
      with the error. To handle the error the strparser is unbound
      from the TCP socket. If the error indicates that the stream
      TCP socket is at recoverable point (ESTRPIPE) then the application
      can read the TCP socket to process the stream. Once the application
      has dealt with the exceptions in the stream, it may again bind the
      socket to a strparser to continue data operations.
      
      Note that ENODATA may be returned to the application. In this case
      parse_msg returned -ESTRPIPE, however strparser was unable to maintain
      synchronization of the stream (i.e. some of the message in question
      was already read by the parser).
      
      strp_pause and strp_unpause are used to provide flow control. For
      instance, if rcv_msg is called but the upper layer can't immediately
      consume the message it can hold the message and pause strparser.
      Signed-off-by: NTom Herbert <tom@herbertland.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      43a0c675
  23. 20 7月, 2016 1 次提交
    • G
      net/ncsi: Resource management · 2d283bdd
      Gavin Shan 提交于
      NCSI spec (DSP0222) defines several objects: package, channel, mode,
      filter, version and statistics etc. This introduces the data structs
      to represent those objects and implement functions to manage them.
      Also, this introduces CONFIG_NET_NCSI for the newly implemented NCSI
      stack.
      
         * The user (e.g. netdev driver) dereference NCSI device by
           "struct ncsi_dev", which is embedded to "struct ncsi_dev_priv".
           The later one is used by NCSI stack internally.
         * Every NCSI device can have multiple packages simultaneously, up
           to 8 packages. It's represented by "struct ncsi_package" and
           identified by 3-bits ID.
         * Every NCSI package can have multiple channels, up to 32. It's
           represented by "struct ncsi_channel" and identified by 5-bits ID.
         * Every NCSI channel has version, statistics, various modes and
           filters. They are represented by "struct ncsi_channel_version",
           "struct ncsi_channel_stats", "struct ncsi_channel_mode" and
           "struct ncsi_channel_filter" separately.
         * Apart from AEN (Asynchronous Event Notification), the NCSI stack
           works in terms of command and response. This introduces "struct
           ncsi_req" to represent a complete NCSI transaction made of NCSI
           request and response.
      
      link: https://www.dmtf.org/sites/default/files/standards/documents/DSP0222_1.1.0.pdfSigned-off-by: NGavin Shan <gwshan@linux.vnet.ibm.com>
      Acked-by: NJoel Stanley <joel@jms.id.au>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      2d283bdd
  24. 17 5月, 2016 2 次提交
    • D
      bpf: add generic constant blinding for use in jits · 4f3446bb
      Daniel Borkmann 提交于
      This work adds a generic facility for use from eBPF JIT compilers
      that allows for further hardening of JIT generated images through
      blinding constants. In response to the original work on BPF JIT
      spraying published by Keegan McAllister [1], most BPF JITs were
      changed to make images read-only and start at a randomized offset
      in the page, where the rest was filled with trap instructions. We
      have this nowadays in x86, arm, arm64 and s390 JIT compilers.
      Additionally, later work also made eBPF interpreter images read
      only for kernels supporting DEBUG_SET_MODULE_RONX, that is, x86,
      arm, arm64 and s390 archs as well currently. This is done by
      default for mentioned JITs when JITing is enabled. Furthermore,
      we had a generic and configurable constant blinding facility on our
      todo for quite some time now to further make spraying harder, and
      first implementation since around netconf 2016.
      
      We found that for systems where untrusted users can load cBPF/eBPF
      code where JIT is enabled, start offset randomization helps a bit
      to make jumps into crafted payload harder, but in case where larger
      programs that cross page boundary are injected, we again have some
      part of the program opcodes at a page start offset. With improved
      guessing and more reliable payload injection, chances can increase
      to jump into such payload. Elena Reshetova recently wrote a test
      case for it [2, 3]. Moreover, eBPF comes with 64 bit constants, which
      can leave some more room for payloads. Note that for all this,
      additional bugs in the kernel are still required to make the jump
      (and of course to guess right, to not jump into a trap) and naturally
      the JIT must be enabled, which is disabled by default.
      
      For helping mitigation, the general idea is to provide an option
      bpf_jit_harden that admins can tweak along with bpf_jit_enable, so
      that for cases where JIT should be enabled for performance reasons,
      the generated image can be further hardened with blinding constants
      for unpriviledged users (bpf_jit_harden == 1), with trading off
      performance for these, but not for privileged ones. We also added
      the option of blinding for all users (bpf_jit_harden == 2), which
      is quite helpful for testing f.e. with test_bpf.ko. There are no
      further e.g. hardening levels of bpf_jit_harden switch intended,
      rationale is to have it dead simple to use as on/off. Since this
      functionality would need to be duplicated over and over for JIT
      compilers to use, which are already complex enough, we provide a
      generic eBPF byte-code level based blinding implementation, which is
      then just transparently JITed. JIT compilers need to make only a few
      changes to integrate this facility and can be migrated one by one.
      
      This option is for eBPF JITs and will be used in x86, arm64, s390
      without too much effort, and soon ppc64 JITs, thus that native eBPF
      can be blinded as well as cBPF to eBPF migrations, so that both can
      be covered with a single implementation. The rule for JITs is that
      bpf_jit_blind_constants() must be called from bpf_int_jit_compile(),
      and in case blinding is disabled, we follow normally with JITing the
      passed program. In case blinding is enabled and we fail during the
      process of blinding itself, we must return with the interpreter.
      Similarly, in case the JITing process after the blinding failed, we
      return normally to the interpreter with the non-blinded code. Meaning,
      interpreter doesn't change in any way and operates on eBPF code as
      usual. For doing this pre-JIT blinding step, we need to make use of
      a helper/auxiliary register, here BPF_REG_AX. This is strictly internal
      to the JIT and not in any way part of the eBPF architecture. Just like
      in the same way as JITs internally make use of some helper registers
      when emitting code, only that here the helper register is one
      abstraction level higher in eBPF bytecode, but nevertheless in JIT
      phase. That helper register is needed since f.e. manually written
      program can issue loads to all registers of eBPF architecture.
      
      The core concept with the additional register is: blind out all 32
      and 64 bit constants by converting BPF_K based instructions into a
      small sequence from K_VAL into ((RND ^ K_VAL) ^ RND). Therefore, this
      is transformed into: BPF_REG_AX := (RND ^ K_VAL), BPF_REG_AX ^= RND,
      and REG <OP> BPF_REG_AX, so actual operation on the target register
      is translated from BPF_K into BPF_X one that is operating on
      BPF_REG_AX's content. During rewriting phase when blinding, RND is
      newly generated via prandom_u32() for each processed instruction.
      64 bit loads are split into two 32 bit loads to make translation and
      patching not too complex. Only basic thing required by JITs is to
      call the helper bpf_jit_blind_constants()/bpf_jit_prog_release_other()
      pair, and to map BPF_REG_AX into an unused register.
      
      Small bpf_jit_disasm extract from [2] when applied to x86 JIT:
      
      echo 0 > /proc/sys/net/core/bpf_jit_harden
      
        ffffffffa034f5e9 + <x>:
        [...]
        39:   mov    $0xa8909090,%eax
        3e:   mov    $0xa8909090,%eax
        43:   mov    $0xa8ff3148,%eax
        48:   mov    $0xa89081b4,%eax
        4d:   mov    $0xa8900bb0,%eax
        52:   mov    $0xa810e0c1,%eax
        57:   mov    $0xa8908eb4,%eax
        5c:   mov    $0xa89020b0,%eax
        [...]
      
      echo 1 > /proc/sys/net/core/bpf_jit_harden
      
        ffffffffa034f1e5 + <x>:
        [...]
        39:   mov    $0xe1192563,%r10d
        3f:   xor    $0x4989b5f3,%r10d
        46:   mov    %r10d,%eax
        49:   mov    $0xb8296d93,%r10d
        4f:   xor    $0x10b9fd03,%r10d
        56:   mov    %r10d,%eax
        59:   mov    $0x8c381146,%r10d
        5f:   xor    $0x24c7200e,%r10d
        66:   mov    %r10d,%eax
        69:   mov    $0xeb2a830e,%r10d
        6f:   xor    $0x43ba02ba,%r10d
        76:   mov    %r10d,%eax
        79:   mov    $0xd9730af,%r10d
        7f:   xor    $0xa5073b1f,%r10d
        86:   mov    %r10d,%eax
        89:   mov    $0x9a45662b,%r10d
        8f:   xor    $0x325586ea,%r10d
        96:   mov    %r10d,%eax
        [...]
      
      As can be seen, original constants that carry payload are hidden
      when enabled, actual operations are transformed from constant-based
      to register-based ones, making jumps into constants ineffective.
      Above extract/example uses single BPF load instruction over and
      over, but of course all instructions with constants are blinded.
      
      Performance wise, JIT with blinding performs a bit slower than just
      JIT and faster than interpreter case. This is expected, since we
      still get all the performance benefits from JITing and in normal
      use-cases not every single instruction needs to be blinded. Summing
      up all 296 test cases averaged over multiple runs from test_bpf.ko
      suite, interpreter was 55% slower than JIT only and JIT with blinding
      was 8% slower than JIT only. Since there are also some extremes in
      the test suite, I expect for ordinary workloads that the performance
      for the JIT with blinding case is even closer to JIT only case,
      f.e. nmap test case from suite has averaged timings in ns 29 (JIT),
      35 (+ blinding), and 151 (interpreter).
      
      BPF test suite, seccomp test suite, eBPF sample code and various
      bigger networking eBPF programs have been tested with this and were
      running fine. For testing purposes, I also adapted interpreter and
      redirected blinded eBPF image to interpreter and also here all tests
      pass.
      
        [1] http://mainisusuallyafunction.blogspot.com/2012/11/attacking-hardened-linux-systems-with.html
        [2] https://github.com/01org/jit-spray-poc-for-ksp/
        [3] http://www.openwall.com/lists/kernel-hardening/2016/05/03/5Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
      Reviewed-by: NElena Reshetova <elena.reshetova@intel.com>
      Acked-by: NAlexei Starovoitov <ast@kernel.org>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      4f3446bb
    • D
      bpf: split HAVE_BPF_JIT into cBPF and eBPF variant · 6077776b
      Daniel Borkmann 提交于
      Split the HAVE_BPF_JIT into two for distinguishing cBPF and eBPF JITs.
      
      Current cBPF ones:
      
        # git grep -n HAVE_CBPF_JIT arch/
        arch/arm/Kconfig:44:    select HAVE_CBPF_JIT
        arch/mips/Kconfig:18:   select HAVE_CBPF_JIT if !CPU_MICROMIPS
        arch/powerpc/Kconfig:129:       select HAVE_CBPF_JIT
        arch/sparc/Kconfig:35:  select HAVE_CBPF_JIT
      
      Current eBPF ones:
      
        # git grep -n HAVE_EBPF_JIT arch/
        arch/arm64/Kconfig:61:  select HAVE_EBPF_JIT
        arch/s390/Kconfig:126:  select HAVE_EBPF_JIT if PACK_STACK && HAVE_MARCH_Z196_FEATURES
        arch/x86/Kconfig:94:    select HAVE_EBPF_JIT                    if X86_64
      
      Later code also needs this facility to check for eBPF JITs.
      Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
      Acked-by: NAlexei Starovoitov <ast@kernel.org>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      6077776b
  25. 09 5月, 2016 1 次提交
  26. 22 3月, 2016 1 次提交
  27. 15 3月, 2016 1 次提交
  28. 10 3月, 2016 1 次提交
  29. 04 3月, 2016 1 次提交
    • A
      net: mellanox: add DEVLINK dependencies · 3d1cbe83
      Arnd Bergmann 提交于
      The new NET_DEVLINK infrastructure can be a loadable module, but the drivers
      using it might be built-in, which causes link errors like:
      
      drivers/net/built-in.o: In function `mlx4_load_one':
      :(.text+0x2fbfda): undefined reference to `devlink_port_register'
      :(.text+0x2fc084): undefined reference to `devlink_port_unregister'
      drivers/net/built-in.o: In function `mlxsw_sx_port_remove':
      :(.text+0x33a03a): undefined reference to `devlink_port_type_clear'
      :(.text+0x33a04e): undefined reference to `devlink_port_unregister'
      
      There are multiple ways to avoid this:
      
      a) add 'depends on NET_DEVLINK || !NET_DEVLINK' dependencies
         for each user
      b) use 'select NET_DEVLINK' from each driver that uses it
         and hide the symbol in Kconfig.
      c) make NET_DEVLINK a 'bool' option so we don't have to
         list it as a dependency, and rely on the APIs to be
         stubbed out when it is disabled
      d) use IS_REACHABLE() rather than IS_ENABLED() to check for
         NET_DEVLINK in include/net/devlink.h
      
      This implements a variation of approach a) by adding an
      intermediate symbol that drivers can depend on, and changes
      the three drivers using it.
      Signed-off-by: NArnd Bergmann <arnd@arndb.de>
      Fixes: 09d4d087 ("mlx4: Implement devlink interface")
      Fixes: c4745500 ("mlxsw: Implement devlink interface")
      Acked-by: NJiri Pirko <jiri@mellanox.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      3d1cbe83
  30. 02 3月, 2016 1 次提交
    • J
      Introduce devlink infrastructure · bfcd3a46
      Jiri Pirko 提交于
      Introduce devlink infrastructure for drivers to register and expose to
      userspace via generic Netlink interface.
      
      There are two basic objects defined:
      devlink - one instance for every "parent device", for example switch ASIC
      devlink port - one instance for every physical port of the device.
      
      This initial portion implements basic get/dump of objects to userspace.
      Also, port splitter and port type setting is implemented.
      Signed-off-by: NJiri Pirko <jiri@mellanox.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      bfcd3a46
  31. 17 2月, 2016 1 次提交
    • P
      net: add dst_cache support · 911362c7
      Paolo Abeni 提交于
      This patch add a generic, lockless dst cache implementation.
      The need for lock is avoided updating the dst cache fields
      only in per cpu scope, and requiring that the cache manipulation
      functions are invoked with the local bh disabled.
      
      The refresh_ts and reset_ts fields are used to ensure the cache
      consistency in case of cuncurrent cache update (dst_cache_set*) and
      reset operation (dst_cache_reset).
      
      Consider the following scenario:
      
      CPU1:                                   	CPU2:
        <cache lookup with emtpy cache: it fails>
        <get dst via uncached route lookup>
      						<related configuration changes>
                                              	dst_cache_reset()
        dst_cache_set()
      
      The dst entry set passed to dst_cache_set() should not be used
      for later dst cache lookup, because it's obtained using old
      configuration values.
      
      Since the refresh_ts is updated only on dst_cache lookup, the
      cached value in the above scenario will be discarded on the next
      lookup.
      Signed-off-by: NPaolo Abeni <pabeni@redhat.com>
      Suggested-and-acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      911362c7
  32. 11 1月, 2016 1 次提交
    • D
      net, sched: add clsact qdisc · 1f211a1b
      Daniel Borkmann 提交于
      This work adds a generalization of the ingress qdisc as a qdisc holding
      only classifiers. The clsact qdisc works on ingress, but also on egress.
      In both cases, it's execution happens without taking the qdisc lock, and
      the main difference for the egress part compared to prior version of [1]
      is that this can be applied with _any_ underlying real egress qdisc (also
      classless ones).
      
      Besides solving the use-case of [1], that is, allowing for more programmability
      on assigning skb->priority for the mqprio case that is supported by most
      popular 10G+ NICs, it also opens up a lot more flexibility for other tc
      applications. The main work on classification can already be done at clsact
      egress time if the use-case allows and state stored for later retrieval
      f.e. again in skb->priority with major/minors (which is checked by most
      classful qdiscs before consulting tc_classify()) and/or in other skb fields
      like skb->tc_index for some light-weight post-processing to get to the
      eventual classid in case of a classful qdisc. Another use case is that
      the clsact egress part allows to have a central egress counterpart to
      the ingress classifiers, so that classifiers can easily share state (e.g.
      in cls_bpf via eBPF maps) for ingress and egress.
      
      Currently, default setups like mq + pfifo_fast would require for this to
      use, for example, prio qdisc instead (to get a tc_classify() run) and to
      duplicate the egress classifier for each queue. With clsact, it allows
      for leaving the setup as is, it can additionally assign skb->priority to
      put the skb in one of pfifo_fast's bands and it can share state with maps.
      Moreover, we can access the skb's dst entry (f.e. to retrieve tclassid)
      w/o the need to perform a skb_dst_force() to hold on to it any longer. In
      lwt case, we can also use this facility to setup dst metadata via cls_bpf
      (bpf_skb_set_tunnel_key()) without needing a real egress qdisc just for
      that (case of IFF_NO_QUEUE devices, for example).
      
      The realization can be done without any changes to the scheduler core
      framework. All it takes is that we have two a-priori defined minors/child
      classes, where we can mux between ingress and egress classifier list
      (dev->ingress_cl_list and dev->egress_cl_list, latter stored close to
      dev->_tx to avoid extra cacheline miss for moderate loads). The egress
      part is a bit similar modelled to handle_ing() and patched to a noop in
      case the functionality is not used. Both handlers are now called
      sch_handle_ingress() and sch_handle_egress(), code sharing among the two
      doesn't seem practical as there are various minor differences in both
      paths, so that making them conditional in a single handler would rather
      slow things down.
      
      Full compatibility to ingress qdisc is provided as well. Since both
      piggyback on TC_H_CLSACT, only one of them (ingress/clsact) can exist
      per netdevice, and thus ingress qdisc specific behaviour can be retained
      for user space. This means, either a user does 'tc qdisc add dev foo ingress'
      and configures ingress qdisc as usual, or the 'tc qdisc add dev foo clsact'
      alternative, where both, ingress and egress classifier can be configured
      as in the below example. ingress qdisc supports attaching classifier to any
      minor number whereas clsact has two fixed minors for muxing between the
      lists, therefore to not break user space setups, they are better done as
      two separate qdiscs.
      
      I decided to extend the sch_ingress module with clsact functionality so
      that commonly used code can be reused, the module is being aliased with
      sch_clsact so that it can be auto-loaded properly. Alternative would have been
      to add a flag when initializing ingress to alter its behaviour plus aliasing
      to a different name (as it's more than just ingress). However, the first would
      end up, based on the flag, choosing the new/old behaviour by calling different
      function implementations to handle each anyway, the latter would require to
      register ingress qdisc once again under different alias. So, this really begs
      to provide a minimal, cleaner approach to have Qdisc_ops and Qdisc_class_ops
      by its own that share callbacks used by both.
      
      Example, adding qdisc:
      
         # tc qdisc add dev foo clsact
         # tc qdisc show dev foo
         qdisc mq 0: root
         qdisc pfifo_fast 0: parent :1 bands 3 priomap  1 2 2 2 1 2 0 0 1 1 1 1 1 1 1 1
         qdisc pfifo_fast 0: parent :2 bands 3 priomap  1 2 2 2 1 2 0 0 1 1 1 1 1 1 1 1
         qdisc pfifo_fast 0: parent :3 bands 3 priomap  1 2 2 2 1 2 0 0 1 1 1 1 1 1 1 1
         qdisc pfifo_fast 0: parent :4 bands 3 priomap  1 2 2 2 1 2 0 0 1 1 1 1 1 1 1 1
         qdisc clsact ffff: parent ffff:fff1
      
      Adding filters (deleting, etc works analogous by specifying ingress/egress):
      
         # tc filter add dev foo ingress bpf da obj bar.o sec ingress
         # tc filter add dev foo egress  bpf da obj bar.o sec egress
         # tc filter show dev foo ingress
         filter protocol all pref 49152 bpf
         filter protocol all pref 49152 bpf handle 0x1 bar.o:[ingress] direct-action
         # tc filter show dev foo egress
         filter protocol all pref 49152 bpf
         filter protocol all pref 49152 bpf handle 0x1 bar.o:[egress] direct-action
      
      A 'tc filter show dev foo' or 'tc filter show dev foo parent ffff:' will
      show an empty list for clsact. Either using the parent names (ingress/egress)
      or specifying the full major/minor will then show the related filter lists.
      
      Prior work on a mqprio prequeue() facility [1] was done mainly by John Fastabend.
      
        [1] http://patchwork.ozlabs.org/patch/512949/Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
      Acked-by: NJohn Fastabend <john.r.fastabend@intel.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      1f211a1b
  33. 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
  34. 30 9月, 2015 1 次提交
  35. 22 7月, 2015 1 次提交
  36. 14 5月, 2015 1 次提交
  37. 07 1月, 2015 1 次提交
  38. 03 12月, 2014 1 次提交