1. 02 Nov, 2017 1 commit
    • Greg Kroah-Hartman's avatar
      License cleanup: add SPDX GPL-2.0 license identifier to files with no license · b2441318
      Greg Kroah-Hartman authored
      Many source files in the tree are missing licensing information, which
      makes it harder for compliance tools to determine the correct license.
      
      By default all files without license information are under the default
      license of the kernel, which is GPL version 2.
      
      Update the files which contain no license information with the 'GPL-2.0'
      SPDX license identifier.  The SPDX identifier is a legally binding
      shorthand, which can be used instead of the full boiler plate text.
      
      This patch is based on work done by Thomas Gleixner and Kate Stewart and
      Philippe Ombredanne.
      
      How this work was done:
      
      Patches were generated and checked against linux-4.14-rc6 for a subset of
      the use cases:
       - file had no licensing information it it.
       - file was a */uapi/* one with no licensing information in it,
       - file was a */uapi/* one with existing licensing information,
      
      Further patches will be generated in subsequent months to fix up cases
      where non-standard license headers were used, and references to license
      had to be inferred by heuristics based on keywords.
      
      The analysis to determine which SPDX License Identifier to be applied to
      a file was done in a spreadsheet of side by side results from of the
      output of two independent scanners (ScanCode & Windriver) producing SPDX
      tag:value files created by Philippe Ombredanne.  Philippe prepared the
      base worksheet, and did an initial spot review of a few 1000 files.
      
      The 4.13 kernel was the starting point of the analysis with 60,537 files
      assessed.  Kate Stewart did a file by file comparison of the scanner
      results in the spreadsheet to determine which SPDX license identifier(s)
      to be applied to the file. She confirmed any determination that was not
      immediately clear with lawyers working with the Linux Foundation.
      
      Criteria used to select files for SPDX license identifier tagging was:
       - Files considered eligible had to be source code files.
       - Make and config files were included as candidates if they contained >5
         lines of source
       - File already had some variant of a license header in it (even if <5
         lines).
      
      All documentation files were explicitly excluded.
      
      The following heuristics were used to determine which SPDX license
      identifiers to apply.
      
       - when both scanners couldn't find any license traces, file was
         considered to have no license information in it, and the top level
         COPYING file license applied.
      
         For non */uapi/* files that summary was:
      
         SPDX license identifier                            # files
         ---------------------------------------------------|-------
         GPL-2.0                                              11139
      
         and resulted in the first patch in this series.
      
         If that file was a */uapi/* path one, it was "GPL-2.0 WITH
         Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:
      
         SPDX license identifier                            # files
         ---------------------------------------------------|-------
         GPL-2.0 WITH Linux-syscall-note                        930
      
         and resulted in the second patch in this series.
      
       - if a file had some form of licensing information in it, and was one
         of the */uapi/* ones, it was denoted with the Linux-syscall-note if
         any GPL family license was found in the file or had no licensing in
         it (per prior point).  Results summary:
      
         SPDX license identifier                            # files
         ---------------------------------------------------|------
         GPL-2.0 WITH Linux-syscall-note                       270
         GPL-2.0+ WITH Linux-syscall-note                      169
         ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
         ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
         LGPL-2.1+ WITH Linux-syscall-note                      15
         GPL-1.0+ WITH Linux-syscall-note                       14
         ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
         LGPL-2.0+ WITH Linux-syscall-note                       4
         LGPL-2.1 WITH Linux-syscall-note                        3
         ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
         ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1
      
         and that resulted in the third patch in this series.
      
       - when the two scanners agreed on the detected license(s), that became
         the concluded license(s).
      
       - when there was disagreement between the two scanners (one detected a
         license but the other didn't, or they both detected different
         licenses) a manual inspection of the file occurred.
      
       - In most cases a manual inspection of the information in the file
         resulted in a clear resolution of the license that should apply (and
         which scanner probably needed to revisit its heuristics).
      
       - When it was not immediately clear, the license identifier was
         confirmed with lawyers working with the Linux Foundation.
      
       - If there was any question as to the appropriate license identifier,
         the file was flagged for further research and to be revisited later
         in time.
      
      In total, over 70 hours of logged manual review was done on the
      spreadsheet to determine the SPDX license identifiers to apply to the
      source files by Kate, Philippe, Thomas and, in some cases, confirmation
      by lawyers working with the Linux Foundation.
      
      Kate also obtained a third independent scan of the 4.13 code base from
      FOSSology, and compared selected files where the other two scanners
      disagreed against that SPDX file, to see if there was new insights.  The
      Windriver scanner is based on an older version of FOSSology in part, so
      they are related.
      
      Thomas did random spot checks in about 500 files from the spreadsheets
      for the uapi headers and agreed with SPDX license identifier in the
      files he inspected. For the non-uapi files Thomas did random spot checks
      in about 15000 files.
      
      In initial set of patches against 4.14-rc6, 3 files were found to have
      copy/paste license identifier errors, and have been fixed to reflect the
      correct identifier.
      
      Additionally Philippe spent 10 hours this week doing a detailed manual
      inspection and review of the 12,461 patched files from the initial patch
      version early this week with:
       - a full scancode scan run, collecting the matched texts, detected
         license ids and scores
       - reviewing anything where there was a license detected (about 500+
         files) to ensure that the applied SPDX license was correct
       - reviewing anything where there was no detection but the patch license
         was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
         SPDX license was correct
      
      This produced a worksheet with 20 files needing minor correction.  This
      worksheet was then exported into 3 different .csv files for the
      different types of files to be modified.
      
      These .csv files were then reviewed by Greg.  Thomas wrote a script to
      parse the csv files and add the proper SPDX tag to the file, in the
      format that the file expected.  This script was further refined by Greg
      based on the output to detect more types of files automatically and to
      distinguish between header and source .c files (which need different
      comment types.)  Finally Greg ran the script using the .csv files to
      generate the patches.
      Reviewed-by: default avatarKate Stewart <kstewart@linuxfoundation.org>
      Reviewed-by: default avatarPhilippe Ombredanne <pombredanne@nexb.com>
      Reviewed-by: default avatarThomas Gleixner <tglx@linutronix.de>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      b2441318
  2. 28 Aug, 2017 1 commit
    • Aaron Conole's avatar
      netfilter: convert hook list to an array · 960632ec
      Aaron Conole authored
      This converts the storage and layout of netfilter hook entries from a
      linked list to an array.  After this commit, hook entries will be
      stored adjacent in memory.  The next pointer is no longer required.
      
      The ops pointers are stored at the end of the array as they are only
      used in the register/unregister path and in the legacy br_netfilter code.
      
      nf_unregister_net_hooks() is slower than needed as it just calls
      nf_unregister_net_hook in a loop (i.e. at least n synchronize_net()
      calls), this will be addressed in followup patch.
      
      Test setup:
       - ixgbe 10gbit
       - netperf UDP_STREAM, 64 byte packets
       - 5 hooks: (raw + mangle prerouting, mangle+filter input, inet filter):
      empty mangle and raw prerouting, mangle and filter input hooks:
      353.9
      this patch:
      364.2
      Signed-off-by: Aaron Conole's avatarAaron Conole <aconole@bytheb.org>
      Signed-off-by: default avatarFlorian Westphal <fw@strlen.de>
      Signed-off-by: default avatarPablo Neira Ayuso <pablo@netfilter.org>
      960632ec
  3. 06 Dec, 2016 1 commit
    • Florian Westphal's avatar
      netfilter: ingress: translate 0 nf_hook_slow retval to -1 · df122f58
      Florian Westphal authored
      The caller assumes that < 0 means that skb was stolen (or free'd).
      
      All other return values continue skb processing.
      
      nf_hook_slow returns 3 different return value types:
      
      A) a (negative) errno value: the skb was dropped (NF_DROP, e.g.
      by iptables '-j DROP' rule).
      
      B) 0. The skb was stolen by the hook or queued to userspace.
      
      C) 1. all hooks returned NF_ACCEPT so the caller should invoke
         the okfn so packet processing can continue.
      
      nft ingress facility currently doesn't have the 'okfn' that
      the NF_HOOK() macros use; there is no nfqueue support either.
      
      So 1 means that nf_hook_ingress() caller should go on processing the skb.
      
      In order to allow use of NF_STOLEN from ingress we need to translate
      this to an errno number, else we'd crash because we continue with
      already-free'd (or about to be free-d) skb.
      
      The errno value isn't checked, its just important that its less than 0,
      so return -1.
      Signed-off-by: default avatarFlorian Westphal <fw@strlen.de>
      Signed-off-by: default avatarPablo Neira Ayuso <pablo@netfilter.org>
      df122f58
  4. 03 Nov, 2016 2 commits
  5. 25 Sep, 2016 1 commit
  6. 24 Sep, 2016 1 commit
  7. 06 Nov, 2015 2 commits
  8. 18 Sep, 2015 1 commit
  9. 14 May, 2015 1 commit
    • Pablo Neira's avatar
      netfilter: add netfilter ingress hook after handle_ing() under unique static key · e687ad60
      Pablo Neira authored
      This patch adds the Netfilter ingress hook just after the existing tc ingress
      hook, that seems to be the consensus solution for this.
      
      Note that the Netfilter hook resides under the global static key that enables
      ingress filtering. Nonetheless, Netfilter still also has its own static key for
      minimal impact on the existing handle_ing().
      
      * Without this patch:
      
      Result: OK: 6216490(c6216338+d152) usec, 100000000 (60byte,0frags)
        16086246pps 7721Mb/sec (7721398080bps) errors: 100000000
      
          42.46%  kpktgend_0   [kernel.kallsyms]   [k] __netif_receive_skb_core
          25.92%  kpktgend_0   [kernel.kallsyms]   [k] kfree_skb
           7.81%  kpktgend_0   [pktgen]            [k] pktgen_thread_worker
           5.62%  kpktgend_0   [kernel.kallsyms]   [k] ip_rcv
           2.70%  kpktgend_0   [kernel.kallsyms]   [k] netif_receive_skb_internal
           2.34%  kpktgend_0   [kernel.kallsyms]   [k] netif_receive_skb_sk
           1.44%  kpktgend_0   [kernel.kallsyms]   [k] __build_skb
      
      * With this patch:
      
      Result: OK: 6214833(c6214731+d101) usec, 100000000 (60byte,0frags)
        16090536pps 7723Mb/sec (7723457280bps) errors: 100000000
      
          41.23%  kpktgend_0      [kernel.kallsyms]  [k] __netif_receive_skb_core
          26.57%  kpktgend_0      [kernel.kallsyms]  [k] kfree_skb
           7.72%  kpktgend_0      [pktgen]           [k] pktgen_thread_worker
           5.55%  kpktgend_0      [kernel.kallsyms]  [k] ip_rcv
           2.78%  kpktgend_0      [kernel.kallsyms]  [k] netif_receive_skb_internal
           2.06%  kpktgend_0      [kernel.kallsyms]  [k] netif_receive_skb_sk
           1.43%  kpktgend_0      [kernel.kallsyms]  [k] __build_skb
      
      * Without this patch + tc ingress:
      
              tc filter add dev eth4 parent ffff: protocol ip prio 1 \
                      u32 match ip dst 4.3.2.1/32
      
      Result: OK: 9269001(c9268821+d179) usec, 100000000 (60byte,0frags)
        10788648pps 5178Mb/sec (5178551040bps) errors: 100000000
      
          40.99%  kpktgend_0   [kernel.kallsyms]  [k] __netif_receive_skb_core
          17.50%  kpktgend_0   [kernel.kallsyms]  [k] kfree_skb
          11.77%  kpktgend_0   [cls_u32]          [k] u32_classify
           5.62%  kpktgend_0   [kernel.kallsyms]  [k] tc_classify_compat
           5.18%  kpktgend_0   [pktgen]           [k] pktgen_thread_worker
           3.23%  kpktgend_0   [kernel.kallsyms]  [k] tc_classify
           2.97%  kpktgend_0   [kernel.kallsyms]  [k] ip_rcv
           1.83%  kpktgend_0   [kernel.kallsyms]  [k] netif_receive_skb_internal
           1.50%  kpktgend_0   [kernel.kallsyms]  [k] netif_receive_skb_sk
           0.99%  kpktgend_0   [kernel.kallsyms]  [k] __build_skb
      
      * With this patch + tc ingress:
      
              tc filter add dev eth4 parent ffff: protocol ip prio 1 \
                      u32 match ip dst 4.3.2.1/32
      
      Result: OK: 9308218(c9308091+d126) usec, 100000000 (60byte,0frags)
        10743194pps 5156Mb/sec (5156733120bps) errors: 100000000
      
          42.01%  kpktgend_0   [kernel.kallsyms]   [k] __netif_receive_skb_core
          17.78%  kpktgend_0   [kernel.kallsyms]   [k] kfree_skb
          11.70%  kpktgend_0   [cls_u32]           [k] u32_classify
           5.46%  kpktgend_0   [kernel.kallsyms]   [k] tc_classify_compat
           5.16%  kpktgend_0   [pktgen]            [k] pktgen_thread_worker
           2.98%  kpktgend_0   [kernel.kallsyms]   [k] ip_rcv
           2.84%  kpktgend_0   [kernel.kallsyms]   [k] tc_classify
           1.96%  kpktgend_0   [kernel.kallsyms]   [k] netif_receive_skb_internal
           1.57%  kpktgend_0   [kernel.kallsyms]   [k] netif_receive_skb_sk
      
      Note that the results are very similar before and after.
      
      I can see gcc gets the code under the ingress static key out of the hot path.
      Then, on that cold branch, it generates the code to accomodate the netfilter
      ingress static key. My explanation for this is that this reduces the pressure
      on the instruction cache for non-users as the new code is out of the hot path,
      and it comes with minimal impact for tc ingress users.
      
      Using gcc version 4.8.4 on:
      
      Architecture:          x86_64
      CPU op-mode(s):        32-bit, 64-bit
      Byte Order:            Little Endian
      CPU(s):                8
      [...]
      L1d cache:             16K
      L1i cache:             64K
      L2 cache:              2048K
      L3 cache:              8192K
      Signed-off-by: default avatarPablo Neira Ayuso <pablo@netfilter.org>
      Acked-by: default avatarAlexei Starovoitov <ast@plumgrid.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      e687ad60