1. 30 Jan, 2018 1 commit
  2. 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
  3. 29 Mar, 2017 1 commit
  4. 28 Mar, 2017 1 commit
  5. 06 Mar, 2017 1 commit
  6. 26 Jul, 2016 1 commit
  7. 23 May, 2016 1 commit
    • Linus Torvalds's avatar
      x86: remove more uaccess_32.h complexity · bd28b145
      Linus Torvalds authored
      
      
      I'm looking at trying to possibly merge the 32-bit and 64-bit versions
      of the x86 uaccess.h implementation, but first this needs to be cleaned
      up.
      
      For example, the 32-bit version of "__copy_from_user_inatomic()" is
      mostly the special cases for the constant size, and it's actually almost
      never relevant.  Most users aren't actually using a constant size
      anyway, and the few cases that do small constant copies are better off
      just using __get_user() instead.
      
      So get rid of the unnecessary complexity.
      
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      bd28b145
  8. 22 May, 2016 1 commit
    • Linus Torvalds's avatar
      x86: remove pointless uaccess_32.h complexity · 5b09c3ed
      Linus Torvalds authored
      
      
      I'm looking at trying to possibly merge the 32-bit and 64-bit versions
      of the x86 uaccess.h implementation, but first this needs to be cleaned
      up.
      
      For example, the 32-bit version of "__copy_to_user_inatomic()" is mostly
      the special cases for the constant size, and it's actually never
      relevant.  Every user except for one aren't actually using a constant
      size anyway, and the one user that uses it is better off just using
      __put_user() instead.
      
      So get rid of the unnecessary complexity.
      
      [ The same cleanup should likely happen to __copy_from_user_inatomic()
        as well, but that one has a lot more users that I need to take a look
        at first ]
      
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      5b09c3ed
  9. 24 Feb, 2016 1 commit
    • Linus Torvalds's avatar
      x86: fix SMAP in 32-bit environments · de9e478b
      Linus Torvalds authored
      In commit 11f1a4b9
      
       ("x86: reorganize SMAP handling in user space
      accesses") I changed how the stac/clac instructions were generated
      around the user space accesses, which then made it possible to do
      batched accesses efficiently for user string copies etc.
      
      However, in doing so, I completely spaced out, and didn't even think
      about the 32-bit case.  And nobody really even seemed to notice, because
      SMAP doesn't even exist until modern Skylake processors, and you'd have
      to be crazy to run 32-bit kernels on a modern CPU.
      
      Which brings us to Andy Lutomirski.
      
      He actually tested the 32-bit kernel on new hardware, and noticed that
      it doesn't work.  My bad.  The trivial fix is to add the required
      uaccess begin/end markers around the raw accesses in <asm/uaccess_32.h>.
      
      I feel a bit bad about this patch, just because that header file really
      should be cleaned up to avoid all the duplicated code in it, and this
      commit just expands on the problem.  But this just fixes the bug without
      any bigger cleanup surgery.
      
      Reported-and-tested-by: default avatarAndy Lutomirski <luto@kernel.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      de9e478b
  10. 19 May, 2015 1 commit
  11. 16 Apr, 2015 1 commit
  12. 26 Oct, 2013 2 commits
    • Jan Beulich's avatar
      x86: Unify copy_to_user() and add size checking to it · 7a3d9b0f
      Jan Beulich authored
      
      
      Similarly to copy_from_user(), where the range check is to
      protect against kernel memory corruption, copy_to_user() can
      benefit from such checking too: Here it protects against kernel
      information leaks.
      
      Signed-off-by: default avatarJan Beulich <jbeulich@suse.com>
      Cc: <arjan@linux.intel.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
      Link: http://lkml.kernel.org/r/5265059502000078000FC4F6@nat28.tlf.novell.com
      
      
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
      Cc: Arjan van de Ven <arjan@linux.intel.com>
      7a3d9b0f
    • Jan Beulich's avatar
      x86: Unify copy_from_user() size checking · 3df7b41a
      Jan Beulich authored
      Commits 4a312769 ("x86: Turn the
      copy_from_user check into an (optional) compile time warning")
      and 63312b6a ("x86: Add a
      Kconfig option to turn the copy_from_user warnings into errors")
      touched only the 32-bit variant of copy_from_user(), whereas the
      original commit 9f0cf4ad ("x86:
      Use __builtin_object_size() to validate the buffer size for
      copy_from_user()") also added the same code to the 64-bit one.
      
      Further the earlier conversion from an inline WARN() to the call
      to copy_from_user_overflow() went a little too far: When the
      number of bytes to be copied is not a constant (e.g. [looking at
      3.11] in drivers/net/tun.c:__tun_chr_ioctl() or
      drivers/pci/pcie/aer/aer_inject.c:aer_inject_write()), the
      compiler will always have to keep the funtion call, and hence
      there will always be a warning. By using __builtin_constant_p()
      we can avoid this.
      
      And then this slightly extends the effect of
      CONFIG_DEBUG_STRICT_USER_COPY_CHECKS in that apart from
      converting warnings to errors in the constant size case, it
      retains the (possibly wrong) warnings in the non-constant size
      case, such that if someone is prepared to get a few false
      positives, (s)he'll be able to recover the current behavior
      (except that these diagnostics now will never be converted to
      errors).
      
      Since the 32-bit variant (intentionally) didn't call
      might_fault(), the unification results in this being called
      twice now. Adding a suitable #ifdef would be the alternative if
      that's a problem.
      
      I'd like to point out though that with
      __compiletime_object_size() being restricted to gcc before 4.6,
      the whole construct is going to become more and more pointless
      going forward. I would question however that commit
      2fb0815c
      
       ("gcc4: disable
      __compiletime_object_size for GCC 4.6+") was really necessary,
      and instead this should have been dealt with as is done here
      from the beginning.
      
      Signed-off-by: default avatarJan Beulich <jbeulich@suse.com>
      Cc: Arjan van de Ven <arjan@linux.intel.com>
      Cc: Guenter Roeck <linux@roeck-us.net>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Link: http://lkml.kernel.org/r/5265056D02000078000FC4F3@nat28.tlf.novell.com
      
      
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
      3df7b41a
  13. 21 Sep, 2012 1 commit
  14. 26 May, 2012 1 commit
  15. 11 Apr, 2012 1 commit
    • Linus Torvalds's avatar
      x86: merge 32/64-bit versions of 'strncpy_from_user()' and speed it up · 92ae03f2
      Linus Torvalds authored
      
      
      This merges the 32- and 64-bit versions of the x86 strncpy_from_user()
      by just rewriting it in C rather than the ancient inline asm versions
      that used lodsb/stosb and had been duplicated for (trivial) differences
      between the 32-bit and 64-bit versions.
      
      While doing that, it also speeds them up by doing the accesses a word at
      a time.  Finally, the new routines also properly handle the case of
      hitting the end of the address space, which we have never done correctly
      before (fs/namei.c has a hack around it for that reason).
      
      Despite all these improvements, it actually removes more lines than it
      adds, due to the de-duplication.  Also, we no longer export (or define)
      the legacy __strncpy_from_user() function (that was defined to not do
      the user permission checks), since it's not actually used anywhere, and
      the user address space checks are built in to the new code.
      
      Other architecture maintainers have been notified that the old hack in
      fs/namei.c will be going away in the 3.5 merge window, in case they
      copied the x86 approach of being a bit cavalier about the end of the
      address space.
      
      Cc: linux-arch@vger.kernel.org
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: Peter Anvin" <hpa@zytor.com>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      92ae03f2
  16. 20 May, 2011 1 commit
    • Linus Torvalds's avatar
      sanitize <linux/prefetch.h> usage · 268bb0ce
      Linus Torvalds authored
      Commit e66eed65
      
       ("list: remove prefetching from regular list
      iterators") removed the include of prefetch.h from list.h, which
      uncovered several cases that had apparently relied on that rather
      obscure header file dependency.
      
      So this fixes things up a bit, using
      
         grep -L linux/prefetch.h $(git grep -l '[^a-z_]prefetchw*(' -- '*.[ch]')
         grep -L 'prefetchw*(' $(git grep -l 'linux/prefetch.h' -- '*.[ch]')
      
      to guide us in finding files that either need <linux/prefetch.h>
      inclusion, or have it despite not needing it.
      
      There are more of them around (mostly network drivers), but this gets
      many core ones.
      
      Reported-by: default avatarStephen Rothwell <sfr@canb.auug.org.au>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      268bb0ce
  17. 05 Jan, 2010 1 commit
  18. 02 Oct, 2009 1 commit
    • Arjan van de Ven's avatar
      x86: Add a Kconfig option to turn the copy_from_user warnings into errors · 63312b6a
      Arjan van de Ven authored
      
      
      For automated testing it is useful to have the option to turn
      the warnings on copy_from_user() etc checks into errors:
      
       In function ‘copy_from_user’,
           inlined from ‘fd_copyin’ at drivers/block/floppy.c:3080,
           inlined from ‘fd_ioctl’ at drivers/block/floppy.c:3503:
         linux/arch/x86/include/asm/uaccess_32.h:213:
        error: call to ‘copy_from_user_overflow’ declared with attribute error:
        copy_from_user buffer size is not provably correct
      
      Signed-off-by: default avatarArjan van de Ven <arjan@linux.intel.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      LKML-Reference: <20091002075050.4e9f7641@infradead.org>
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      63312b6a
  19. 01 Oct, 2009 1 commit
    • Arjan van de Ven's avatar
      x86: Turn the copy_from_user check into an (optional) compile time warning · 4a312769
      Arjan van de Ven authored
      
      
      A previous patch added the buffer size check to copy_from_user().
      
      One of the things learned from analyzing the result of the previous
      patch is that in general, gcc is really good at proving that the
      code contains sufficient security checks to not need to do a
      runtime check. But that for those cases where gcc could not prove
      this, there was a relatively high percentage of real security
      issues.
      
      This patch turns the case of "gcc cannot prove" into a compile time
      warning, as long as a sufficiently new gcc is in use that supports
      this. The objective is that these warnings will trigger developers
      checking new cases out before a security hole enters a linux kernel
      release.
      
      Signed-off-by: default avatarArjan van de Ven <arjan@linux.intel.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: "David S. Miller" <davem@davemloft.net>
      Cc: James Morris <jmorris@namei.org>
      Cc: Jan Beulich <jbeulich@novell.com>
      LKML-Reference: <20090930130523.348ae6c4@infradead.org>
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      4a312769
  20. 26 Sep, 2009 1 commit
    • Arjan van de Ven's avatar
      x86: Use __builtin_object_size() to validate the buffer size for copy_from_user() · 9f0cf4ad
      Arjan van de Ven authored
      
      
      gcc (4.x) supports the __builtin_object_size() builtin, which
      reports the size of an object that a pointer point to, when known
      at compile time. If the buffer size is not known at compile time, a
      constant -1 is returned.
      
      This patch uses this feature to add a sanity check to
      copy_from_user(); if the target buffer is known to be smaller than
      the copy size, the copy is aborted and a WARNing is emitted in
      memory debug mode.
      
      These extra checks compile away when the object size is not known,
      or if both the buffer size and the copy length are constants.
      
      Signed-off-by: default avatarArjan van de Ven <arjan@linux.intel.com>
      LKML-Reference: <20090926143301.2c396b94@infradead.org>
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      9f0cf4ad
  21. 20 Sep, 2009 1 commit
  22. 02 Mar, 2009 1 commit
    • Ingo Molnar's avatar
      x86, mm: dont use non-temporal stores in pagecache accesses · f1800536
      Ingo Molnar authored
      Impact: standardize IO on cached ops
      
      On modern CPUs it is almost always a bad idea to use non-temporal stores,
      as the regression in this commit has shown it:
      
        30d697fa
      
      : x86: fix performance regression in write() syscall
      
      The kernel simply has no good information about whether using non-temporal
      stores is a good idea or not - and trying to add heuristics only increases
      complexity and inserts fragility.
      
      The regression on cached write()s took very long to be found - over two
      years. So dont take any chances and let the hardware decide how it makes
      use of its caches.
      
      The only exception is drivers/gpu/drm/i915/i915_gem.c: there were we are
      absolutely sure that another entity (the GPU) will pick up the dirty
      data immediately and that the CPU will not touch that data before the
      GPU will.
      
      Also, keep the _nocache() primitives to make it easier for people to
      experiment with these details. There may be more clear-cut cases where
      non-cached copies can be used, outside of filemap.c.
      
      Cc: Salman Qazi <sqazi@google.com>
      Cc: Nick Piggin <npiggin@suse.de>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      f1800536
  23. 25 Feb, 2009 1 commit
    • Ingo Molnar's avatar
      x86, mm: pass in 'total' to __copy_from_user_*nocache() · 3255aa2e
      Ingo Molnar authored
      
      
      Impact: cleanup, enable future change
      
      Add a 'total bytes copied' parameter to __copy_from_user_*nocache(),
      and update all the callsites.
      
      The parameter is not used yet - architecture code can use it to
      more intelligently decide whether the copy should be cached or
      non-temporal.
      
      Cc: Salman Qazi <sqazi@google.com>
      Cc: Nick Piggin <npiggin@suse.de>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      3255aa2e
  24. 23 Oct, 2008 2 commits
  25. 11 Sep, 2008 1 commit
  26. 10 Sep, 2008 1 commit
    • Nick Piggin's avatar
      x86: some lock annotations for user copy paths · c10d38dd
      Nick Piggin authored
      
      
      copy_to/from_user and all its variants (except the atomic ones) can take a
      page fault and perform non-trivial work like taking mmap_sem and entering
      the filesyste/pagecache.
      
      Unfortunately, this often escapes lockdep because a common pattern is to
      use it to read in some arguments just set up from userspace, or write data
      back to a hot buffer. In those cases, it will be unlikely for page reclaim
      to get a window in to cause copy_*_user to fault.
      
      With the new might_lock primitives, add some annotations to x86. I don't
      know if I caught all possible faulting points (it's a bit of a maze, and I
      didn't really look at 32-bit). But this is a starting point.
      
      Boots and runs OK so far.
      
      Signed-off-by: default avatarNick Piggin <npiggin@suse.de>
      Acked-by: default avatarPeter Zijlstra <a.p.zijlstra@chello.nl>
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      c10d38dd
  27. 22 Jul, 2008 1 commit
    • Vegard Nossum's avatar
      x86: consolidate header guards · 77ef50a5
      Vegard Nossum authored
      
      
      This patch is the result of an automatic script that consolidates the
      format of all the headers in include/asm-x86/.
      
      The format:
      
      1. No leading underscore. Names with leading underscores are reserved.
      2. Pathname components are separated by two underscores. So we can
         distinguish between mm_types.h and mm/types.h.
      3. Everything except letters and numbers are turned into single
         underscores.
      
      Signed-off-by: default avatarVegard Nossum <vegard.nossum@gmail.com>
      77ef50a5
  28. 09 Jul, 2008 11 commits