1. 03 4月, 2018 17 次提交
  2. 25 1月, 2018 7 次提交
  3. 20 1月, 2018 1 次提交
  4. 11 1月, 2018 1 次提交
  5. 10 1月, 2018 1 次提交
    • A
      bpf: introduce BPF_JIT_ALWAYS_ON config · 290af866
      Alexei Starovoitov 提交于
      The BPF interpreter has been used as part of the spectre 2 attack CVE-2017-5715.
      
      A quote from goolge project zero blog:
      "At this point, it would normally be necessary to locate gadgets in
      the host kernel code that can be used to actually leak data by reading
      from an attacker-controlled location, shifting and masking the result
      appropriately and then using the result of that as offset to an
      attacker-controlled address for a load. But piecing gadgets together
      and figuring out which ones work in a speculation context seems annoying.
      So instead, we decided to use the eBPF interpreter, which is built into
      the host kernel - while there is no legitimate way to invoke it from inside
      a VM, the presence of the code in the host kernel's text section is sufficient
      to make it usable for the attack, just like with ordinary ROP gadgets."
      
      To make attacker job harder introduce BPF_JIT_ALWAYS_ON config
      option that removes interpreter from the kernel in favor of JIT-only mode.
      So far eBPF JIT is supported by:
      x64, arm64, arm32, sparc64, s390, powerpc64, mips64
      
      The start of JITed program is randomized and code page is marked as read-only.
      In addition "constant blinding" can be turned on with net.core.bpf_jit_harden
      
      v2->v3:
      - move __bpf_prog_ret0 under ifdef (Daniel)
      
      v1->v2:
      - fix init order, test_bpf and cBPF (Daniel's feedback)
      - fix offloaded bpf (Jakub's feedback)
      - add 'return 0' dummy in case something can invoke prog->bpf_func
      - retarget bpf tree. For bpf-next the patch would need one extra hunk.
        It will be sent when the trees are merged back to net-next
      
      Considered doing:
        int bpf_jit_enable __read_mostly = BPF_EBPF_JIT_DEFAULT;
      but it seems better to land the patch as-is and in bpf-next remove
      bpf_jit_enable global variable from all JITs, consolidate in one place
      and remove this jit_init() function.
      Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
      Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
      290af866
  6. 19 12月, 2017 1 次提交
    • T
      sock: Move the socket inuse to namespace. · 648845ab
      Tonghao Zhang 提交于
      In some case, we want to know how many sockets are in use in
      different _net_ namespaces. It's a key resource metric.
      
      This patch add a member in struct netns_core. This is a counter
      for socket-inuse in the _net_ namespace. The patch will add/sub
      counter in the sk_alloc, sk_clone_lock and __sk_free.
      
      This patch will not counter the socket created in kernel.
      It's not very useful for userspace to know how many kernel
      sockets we created.
      
      The main reasons for doing this are that:
      
      1. When linux calls the 'do_exit' for process to exit, the functions
      'exit_task_namespaces' and 'exit_task_work' will be called sequentially.
      'exit_task_namespaces' may have destroyed the _net_ namespace, but
      'sock_release' called in 'exit_task_work' may use the _net_ namespace
      if we counter the socket-inuse in sock_release.
      
      2. socket and sock are in pair. More important, sock holds the _net_
      namespace. We counter the socket-inuse in sock, for avoiding holding
      _net_ namespace again in socket. It's a easy way to maintain the code.
      Signed-off-by: NMartin Zhang <zhangjunweimartin@didichuxing.com>
      Signed-off-by: NTonghao Zhang <zhangtonghao@didichuxing.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      648845ab
  7. 06 12月, 2017 2 次提交
  8. 28 11月, 2017 2 次提交
  9. 16 11月, 2017 1 次提交
  10. 17 8月, 2017 1 次提交
  11. 02 8月, 2017 1 次提交
  12. 26 7月, 2017 1 次提交
  13. 25 7月, 2017 1 次提交
  14. 05 7月, 2017 1 次提交
  15. 14 6月, 2017 1 次提交
  16. 23 5月, 2017 1 次提交