Commit Graph

12 Commits

Author SHA1 Message Date
Masahiro Yamada
c7c0eecf89 kbuild: re-implement detection of CONFIG options leaked to user-space
scripts/headers_check.pl can detect references to CONFIG options in
exported headers, but it has been disabled for more than a decade.

Reverting commit 7e3fa56141 ("kbuild: drop check for CONFIG_ in
headers_check") would emit the following warnings for headers_check
on x86:

usr/include/mtd/ubi-user.h:283: leaks CONFIG_MTD_UBI_BEB_LIMIT to userspace where it is not valid
usr/include/linux/cm4000_cs.h:26: leaks CONFIG_COMPAT to userspace where it is not valid
usr/include/linux/pkt_cls.h:301: leaks CONFIG_NET_CLS_ACT to userspace where it is not valid
usr/include/linux/videodev2.h:2465: leaks CONFIG_VIDEO_ADV_DEBUG to userspace where it is not valid
usr/include/linux/bpf.h:249: leaks CONFIG_EFFICIENT_UNALIGNED_ACCESS to userspace where it is not valid
usr/include/linux/bpf.h:819: leaks CONFIG_CGROUP_NET_CLASSID to userspace where it is not valid
usr/include/linux/bpf.h:1011: leaks CONFIG_IP_ROUTE_CLASSID to userspace where it is not valid
usr/include/linux/bpf.h:1742: leaks CONFIG_BPF_KPROBE_OVERRIDE to userspace where it is not valid
usr/include/linux/bpf.h:1747: leaks CONFIG_FUNCTION_ERROR_INJECTION to userspace where it is not valid
usr/include/linux/bpf.h:1936: leaks CONFIG_XFRM to userspace where it is not valid
usr/include/linux/bpf.h:2184: leaks CONFIG_BPF_LIRC_MODE2 to userspace where it is not valid
usr/include/linux/bpf.h:2210: leaks CONFIG_BPF_LIRC_MODE2 to userspace where it is not valid
usr/include/linux/bpf.h:2227: leaks CONFIG_SOCK_CGROUP_DATA to userspace where it is not valid
usr/include/linux/bpf.h:2311: leaks CONFIG_NET to userspace where it is not valid
usr/include/linux/bpf.h:2348: leaks CONFIG_NET to userspace where it is not valid
usr/include/linux/bpf.h:2422: leaks CONFIG_BPF_LIRC_MODE2 to userspace where it is not valid
usr/include/linux/bpf.h:2528: leaks CONFIG_NET to userspace where it is not valid
usr/include/linux/pktcdvd.h:37: leaks CONFIG_CDROM_PKTCDVD_WCACHE to userspace where it is not valid
usr/include/linux/hw_breakpoint.h:27: leaks CONFIG_HAVE_MIXED_BREAKPOINTS_REGS to userspace where it is not valid
usr/include/linux/raw.h:17: leaks CONFIG_MAX_RAW_DEVS to userspace where it is not valid
usr/include/linux/elfcore.h:62: leaks CONFIG_BINFMT_ELF_FDPIC to userspace where it is not valid
usr/include/linux/eventpoll.h:82: leaks CONFIG_PM_SLEEP to userspace where it is not valid
usr/include/linux/atmdev.h:104: leaks CONFIG_COMPAT to userspace where it is not valid
usr/include/asm-generic/unistd.h:651: leaks CONFIG_MMU to userspace where it is not valid
usr/include/asm-generic/bitsperlong.h:9: leaks CONFIG_64BIT to userspace where it is not valid
usr/include/asm-generic/fcntl.h:119: leaks CONFIG_64BIT to userspace where it is not valid
usr/include/asm/auxvec.h:14: leaks CONFIG_IA32_EMULATION to userspace where it is not valid
usr/include/asm/e820.h:14: leaks CONFIG_NODES_SHIFT to userspace where it is not valid
usr/include/asm/e820.h:39: leaks CONFIG_X86_PMEM_LEGACY to userspace where it is not valid
usr/include/asm/e820.h:49: leaks CONFIG_INTEL_TXT to userspace where it is not valid
usr/include/asm/mman.h:7: leaks CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS to userspace where it is not valid

Most of these are false positives because scripts/headers_check.pl
parses comment lines.

It is also false negative. arch/x86/include/uapi/asm/auxvec.h contains
CONFIG_IA32_EMULATION and CONFIG_X86_64, but the only former is reported.

It would be possible to fix scripts/headers_check.pl, of course.
However, we already have some duplicated checks between headers_check
and CONFIG_UAPI_HEADER_TEST. At this moment of time, there are still
dozens of headers excluded from the header test (usr/include/Makefile),
but we might be able to remove headers_check eventually.

I re-implemented it in scripts/headers_install.sh by using sed because
the most of code in scripts/headers_install.sh is written in sed.

This patch works like this:

[1] Run scripts/unifdef first because we need to drop the code
    surrounded by #ifdef __KERNEL__ ... #endif

[2] Remove all C style comments. The sed code is somewhat complicated
    since we need to deal with both single and multi line comments.

    Precisely speaking, a comment block is replaced with a space just
    in case.

      CONFIG_FOO/* this is a comment */CONFIG_BAR

    should be converted into:

      CONFIG_FOO CONFIG_BAR

    instead of:

      CONFIG_FOOCONFIG_BAR

[3] Match CONFIG_... pattern. It correctly matches to all CONFIG
    options that appear in a single line.

After this commit, this would detect the following warnings, all of
which are real ones.

warning: include/uapi/linux/pktcdvd.h: leak CONFIG_CDROM_PKTCDVD_WCACHE to user-space
warning: include/uapi/linux/hw_breakpoint.h: leak CONFIG_HAVE_MIXED_BREAKPOINTS_REGS to user-space
warning: include/uapi/linux/raw.h: leak CONFIG_MAX_RAW_DEVS to user-space
warning: include/uapi/linux/elfcore.h: leak CONFIG_BINFMT_ELF_FDPIC to user-space
warning: include/uapi/linux/eventpoll.h: leak CONFIG_PM_SLEEP to user-space
warning: include/uapi/linux/atmdev.h: leak CONFIG_COMPAT to user-space
warning: include/uapi/asm-generic/fcntl.h: leak CONFIG_64BIT to user-space
warning: arch/x86/include/uapi/asm/auxvec.h: leak CONFIG_IA32_EMULATION to user-space
warning: arch/x86/include/uapi/asm/auxvec.h: leak CONFIG_X86_64 to user-space
warning: arch/x86/include/uapi/asm/mman.h: leak CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS to user-space

However, it is not nice to show them right now. I created a list of
existing leakages. They are not warned, but a new leakage will be
blocked by the 0-day bot.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
2019-08-21 21:05:21 +09:00
Masahiro Yamada
622445541b kbuild: detect missing "WITH Linux-syscall-note" for uapi headers
UAPI headers licensed under GPL are supposed to have exception
"WITH Linux-syscall-note" so that they can be included into non-GPL
user space application code.

Unfortunately, people often miss to add it. Break 'make headers'
when any of exported headers lacks the exception note so that the
0-day bot can easily catch it.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-07-29 10:05:41 +09:00
Masahiro Yamada
555187a879 kbuild: simplify scripts/headers_install.sh
Now that headers_install.sh is invoked per file, remove the for-loop
in the shell script.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-06-15 19:57:02 +09:00
Michael Forney
1fe7d2bb24 kbuild: Improve portability of some sed invocations
* Use BREs where EREs aren't necessary.
* Pass -E instead of -r to use EREs. This will be standardized in the
  next POSIX revision[0]. GNU sed supports this since 4.2 (May 2009),
  and busybox since 1.22.0 (Jan 2014).
* Use the [:space:] character class instead of ` \t` in bracket
  expressions. In bracket expressions, POSIX says that <backslash> loses
  its special meaning, so a conforming implementation cannot expand \t
  to <tab>[1].
* In BREs, use interval expressions (\{n,m\}) instead of non-standard
  features like \+ and \?.
* Use a loop instead of -s flag.

There are still plenty of other cases of non-standard sed invocations
(use of ERE features in BREs, in-place editing), but this fixes some
core ones.

[0] http://austingroupbugs.net/view.php?id=528
[1] http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap09.html#tag_09_03_05

Signed-off-by: Michael Forney <forney@google.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-03-26 02:01:18 +09:00
Ingo Molnar
8c5db92a70 Merge branch 'linus' into locking/core, to resolve conflicts
Conflicts:
	include/linux/compiler-clang.h
	include/linux/compiler-gcc.h
	include/linux/compiler-intel.h
	include/uapi/linux/stddef.h

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-07 10:32:44 +01:00
Greg Kroah-Hartman
b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license
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>
2017-11-02 11:10:55 +01:00
Will Deacon
d15155824c linux/compiler.h: Split into compiler.h and compiler_types.h
linux/compiler.h is included indirectly by linux/types.h via
uapi/linux/types.h -> uapi/linux/posix_types.h -> linux/stddef.h
-> uapi/linux/stddef.h and is needed to provide a proper definition of
offsetof.

Unfortunately, compiler.h requires a definition of
smp_read_barrier_depends() for defining lockless_dereference() and soon
for defining READ_ONCE(), which means that all
users of READ_ONCE() will need to include asm/barrier.h to avoid splats
such as:

   In file included from include/uapi/linux/stddef.h:1:0,
                    from include/linux/stddef.h:4,
                    from arch/h8300/kernel/asm-offsets.c:11:
   include/linux/list.h: In function 'list_empty':
>> include/linux/compiler.h:343:2: error: implicit declaration of function 'smp_read_barrier_depends' [-Werror=implicit-function-declaration]
     smp_read_barrier_depends(); /* Enforce dependency ordering from x */ \
     ^

A better alternative is to include asm/barrier.h in linux/compiler.h,
but this requires a type definition for "bool" on some architectures
(e.g. x86), which is defined later by linux/types.h. Type "bool" is also
used directly in linux/compiler.h, so the whole thing is pretty fragile.

This patch splits compiler.h in two: compiler_types.h contains type
annotations, definitions and the compiler-specific parts, whereas
compiler.h #includes compiler-types.h and additionally defines macros
such as {READ,WRITE.ACCESS}_ONCE().

uapi/linux/stddef.h and linux/linkage.h are then moved over to include
linux/compiler_types.h, which fixes the build for h8 and blackfin.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1508840570-22169-2-git-send-email-will.deacon@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-10-24 13:17:32 +02:00
Linus Torvalds
f33a3faa25 Merge branch 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild
Pull kbuild changes from Michal Marek:
 - fix for handling dependencies of *-objs targets by Masahiro Yamada
 - lots of cleanups in the kbuild machinery, also by Masahiro
 - fixes for the kconfig build to use an UTF-8 capable ncurses library
   if possible and to build on not-so-standard installs
 - some more minor fixes

* 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
  kbuild: Do not reference *-n variables in the Makefile
  kbuild: simplify build, clean, modbuiltin shorthands
  kbuild: arm: Do not define "comma" twice
  kbuild: remove obj-n and lib-n handling
  kbuild: remove unnecessary variable initializaions
  kbuild: remove unnecessary "obj- := dummy.o" trick
  kbuild: handle C=... and M=... after entering into build directory
  kbuild: use $(Q) for sub-make target
  kbuild: fake the "Entering directory ..." message more simply
  kconfig/lxdialog: get ncurses CFLAGS with pkg-config
  kconfig: nconfig: fix multi-byte UTF handling
  kconfig: lxdialog: fix spelling
  kbuild: Make scripts executable
  kbuild: remove redundant clean-files from scripts/kconfig/Makefile
  kbuild: refactor script/kconfig/Makefile
  kbuild: handle the dependency of multi-objs hostprogs appropriately
  kbuild: handle multi-objs dependency appropriately
2014-10-14 09:22:26 +02:00
Javier Barrio
f9a4d1103c scripts/headers_install.sh: fix error handling
- headers_install requires at least two arguments

- missed closing quote

Signed-off-by: Javier Barrio <javier.barrio.mart@gmail.com>
Cc: Michal Marek <mmarek@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-10-14 02:18:23 +02:00
Michal Marek
06ed5c2bfa kbuild: Make scripts executable
The Makefiles call the respective interpreter explicitly, but this makes
it easier to use the scripts manually.

Signed-off-by: Michal Marek <mmarek@suse.cz>
2014-08-20 16:03:45 +02:00
Nicolas Dichtel
c0ff68f161 kbuild: fix make headers_install when path is too long
If headers_install is executed from a deep/long directory structure, the
shell's maximum argument length can be execeeded, which breaks the operation
with:

| make[2]: execvp: /bin/sh: Argument list too long
| make[2]: ***

Instead of passing each files name with the entire path, I give only the file
name without the source path and give this path as a new argument to
headers_install.pl.

Because there is three possible paths, I have tree input-files list, one per
path.

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Tested-by: Bruce Ashfield <bruce.ashfield@windriver.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2013-05-17 22:10:35 +02:00
Rob Landley
e0e2fa4b51 headers_install.pl: convert to headers_install.sh
Remove perl from make headers_install by replacing a perl script (doing a
simple regex search and replace) with a smaller, faster, simpler,
POSIX-2008 shell script implementation.  The new shell script is a single
for loop calling sed and piping its output through unifdef to produce the
target file.

Same as last time except for minor tweak to deal with code review from
here: http://lkml.indiana.edu/hypermail/linux/kernel/1302.3/00078.html

(Note that this drops the "arch" argument, which isn't used. Kbuild
already points to the right input files on the command line.)

Signed-off-by: Rob Landley <rob@landley.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Josh Boyer <jwboyer@redhat.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: David Howells <dhowell@redhat.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2013-04-09 12:50:29 +02:00