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: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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 <aconole@bytheb.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This field is only useful for nf_queue, so store it in the
nf_queue_entry structure instead, away from the core path. Pass
hook_head to nf_hook_slow().
Since we always have a valid entry on the first iteration in
nf_iterate(), we can use 'do { ... } while (entry)' loop instead.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Patch c5136b15ea ("netfilter: bridge: add and use br_nf_hook_thresh")
introduced br_nf_hook_thresh().
Replace NF_HOOK_THRESH() by br_nf_hook_thresh from
br_nf_forward_finish(), so we have no more callers for this macro.
As a result, state->thresh and explicit thresh parameter in the hook
state structure is not required anymore. And we can get rid of
skip-hook-under-thresh loop in nf_iterate() in the core path that is
only used by br_netfilter to search for the filter hook.
Suggested-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The netfilter hook list never uses the prev pointer, and so can be trimmed to
be a simple singly-linked list.
In addition to having a more light weight structure for hook traversal,
struct net becomes 5568 bytes (down from 6400) and struct net_device becomes
2176 bytes (down from 2240).
Signed-off-by: Aaron Conole <aconole@bytheb.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This makes things simpler because we can store the head of the list
in the nf_state structure without worrying about concurrent add/delete
of hook elements from the list.
A future commit will make use of this to implement a simpler
linked-list.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Aaron Conole <aconole@bytheb.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The input and output interfaces in nf_hook_state_init() are flipped.
This fixes iif matching on nftables.
Reported-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
nf_hook_list_active() always returns true once at least one device has
NF_INGRESS hook enabled.
Thus, don't use this function. Instead, inverse the test and use the static
key to elide list_empty test if no NF_INGRESS hooks are active.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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: Pablo Neira Ayuso <pablo@netfilter.org>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Greg Kroah-Hartman