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>
2017-11-01 21:07:57 +07:00
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/* SPDX-License-Identifier: GPL-2.0 */
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2006-06-23 16:04:16 +07:00
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#ifndef __LINUX_UACCESS_H__
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#define __LINUX_UACCESS_H__
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2015-05-11 22:52:06 +07:00
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#include <linux/sched.h>
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2016-12-28 06:14:09 +07:00
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#include <linux/thread_info.h>
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2017-03-21 08:56:06 +07:00
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#include <linux/kasan-checks.h>
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2016-12-28 06:00:15 +07:00
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2017-03-21 08:08:07 +07:00
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#define uaccess_kernel() segment_eq(get_fs(), KERNEL_DS)
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2006-06-23 16:04:16 +07:00
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#include <asm/uaccess.h>
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2017-03-21 08:56:06 +07:00
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/*
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* Architectures should provide two primitives (raw_copy_{to,from}_user())
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2017-04-06 06:15:53 +07:00
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* and get rid of their private instances of copy_{to,from}_user() and
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* __copy_{to,from}_user{,_inatomic}().
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2017-03-21 08:56:06 +07:00
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*
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* raw_copy_{to,from}_user(to, from, size) should copy up to size bytes and
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* return the amount left to copy. They should assume that access_ok() has
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* already been checked (and succeeded); they should *not* zero-pad anything.
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* No KASAN or object size checks either - those belong here.
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*
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* Both of these functions should attempt to copy size bytes starting at from
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* into the area starting at to. They must not fetch or store anything
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* outside of those areas. Return value must be between 0 (everything
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* copied successfully) and size (nothing copied).
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*
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* If raw_copy_{to,from}_user(to, from, size) returns N, size - N bytes starting
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* at to must become equal to the bytes fetched from the corresponding area
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* starting at from. All data past to + size - N must be left unmodified.
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*
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* If copying succeeds, the return value must be 0. If some data cannot be
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* fetched, it is permitted to copy less than had been fetched; the only
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* hard requirement is that not storing anything at all (i.e. returning size)
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* should happen only when nothing could be copied. In other words, you don't
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* have to squeeze as much as possible - it is allowed, but not necessary.
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*
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* For raw_copy_from_user() to always points to kernel memory and no faults
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* on store should happen. Interpretation of from is affected by set_fs().
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* For raw_copy_to_user() it's the other way round.
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*
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* Both can be inlined - it's up to architectures whether it wants to bother
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* with that. They should not be used directly; they are used to implement
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* the 6 functions (copy_{to,from}_user(), __copy_{to,from}_user_inatomic())
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* that are used instead. Out of those, __... ones are inlined. Plain
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* copy_{to,from}_user() might or might not be inlined. If you want them
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* inlined, have asm/uaccess.h define INLINE_COPY_{TO,FROM}_USER.
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*
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* NOTE: only copy_from_user() zero-pads the destination in case of short copy.
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* Neither __copy_from_user() nor __copy_from_user_inatomic() zero anything
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* at all; their callers absolutely must check the return value.
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*
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* Biarch ones should also provide raw_copy_in_user() - similar to the above,
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* but both source and destination are __user pointers (affected by set_fs()
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* as usual) and both source and destination can trigger faults.
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*/
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static __always_inline unsigned long
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__copy_from_user_inatomic(void *to, const void __user *from, unsigned long n)
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{
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kasan_check_write(to, n);
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check_object_size(to, n, false);
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return raw_copy_from_user(to, from, n);
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}
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static __always_inline unsigned long
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__copy_from_user(void *to, const void __user *from, unsigned long n)
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{
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might_fault();
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kasan_check_write(to, n);
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check_object_size(to, n, false);
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return raw_copy_from_user(to, from, n);
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}
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/**
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* __copy_to_user_inatomic: - Copy a block of data into user space, with less checking.
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* @to: Destination address, in user space.
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* @from: Source address, in kernel space.
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* @n: Number of bytes to copy.
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*
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* Context: User context only.
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*
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* Copy data from kernel space to user space. Caller must check
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* the specified block with access_ok() before calling this function.
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* The caller should also make sure he pins the user space address
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* so that we don't result in page fault and sleep.
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*/
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static __always_inline unsigned long
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__copy_to_user_inatomic(void __user *to, const void *from, unsigned long n)
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{
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kasan_check_read(from, n);
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check_object_size(from, n, true);
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return raw_copy_to_user(to, from, n);
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}
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static __always_inline unsigned long
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__copy_to_user(void __user *to, const void *from, unsigned long n)
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{
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might_fault();
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kasan_check_read(from, n);
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check_object_size(from, n, true);
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return raw_copy_to_user(to, from, n);
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}
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#ifdef INLINE_COPY_FROM_USER
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static inline unsigned long
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_copy_from_user(void *to, const void __user *from, unsigned long n)
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{
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unsigned long res = n;
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2017-06-30 08:39:54 +07:00
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might_fault();
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Remove 'type' argument from access_ok() function
Nobody has actually used the type (VERIFY_READ vs VERIFY_WRITE) argument
of the user address range verification function since we got rid of the
old racy i386-only code to walk page tables by hand.
It existed because the original 80386 would not honor the write protect
bit when in kernel mode, so you had to do COW by hand before doing any
user access. But we haven't supported that in a long time, and these
days the 'type' argument is a purely historical artifact.
A discussion about extending 'user_access_begin()' to do the range
checking resulted this patch, because there is no way we're going to
move the old VERIFY_xyz interface to that model. And it's best done at
the end of the merge window when I've done most of my merges, so let's
just get this done once and for all.
This patch was mostly done with a sed-script, with manual fix-ups for
the cases that weren't of the trivial 'access_ok(VERIFY_xyz' form.
There were a couple of notable cases:
- csky still had the old "verify_area()" name as an alias.
- the iter_iov code had magical hardcoded knowledge of the actual
values of VERIFY_{READ,WRITE} (not that they mattered, since nothing
really used it)
- microblaze used the type argument for a debug printout
but other than those oddities this should be a total no-op patch.
I tried to fix up all architectures, did fairly extensive grepping for
access_ok() uses, and the changes are trivial, but I may have missed
something. Any missed conversion should be trivially fixable, though.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-01-04 09:57:57 +07:00
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if (likely(access_ok(from, n))) {
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2017-06-30 08:39:54 +07:00
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kasan_check_write(to, n);
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2017-03-21 08:56:06 +07:00
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res = raw_copy_from_user(to, from, n);
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2017-06-30 08:39:54 +07:00
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}
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2017-03-21 08:56:06 +07:00
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if (unlikely(res))
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memset(to + (n - res), 0, res);
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return res;
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}
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#else
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extern unsigned long
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_copy_from_user(void *, const void __user *, unsigned long);
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#endif
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#ifdef INLINE_COPY_TO_USER
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static inline unsigned long
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_copy_to_user(void __user *to, const void *from, unsigned long n)
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{
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2017-06-30 08:39:54 +07:00
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might_fault();
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Remove 'type' argument from access_ok() function
Nobody has actually used the type (VERIFY_READ vs VERIFY_WRITE) argument
of the user address range verification function since we got rid of the
old racy i386-only code to walk page tables by hand.
It existed because the original 80386 would not honor the write protect
bit when in kernel mode, so you had to do COW by hand before doing any
user access. But we haven't supported that in a long time, and these
days the 'type' argument is a purely historical artifact.
A discussion about extending 'user_access_begin()' to do the range
checking resulted this patch, because there is no way we're going to
move the old VERIFY_xyz interface to that model. And it's best done at
the end of the merge window when I've done most of my merges, so let's
just get this done once and for all.
This patch was mostly done with a sed-script, with manual fix-ups for
the cases that weren't of the trivial 'access_ok(VERIFY_xyz' form.
There were a couple of notable cases:
- csky still had the old "verify_area()" name as an alias.
- the iter_iov code had magical hardcoded knowledge of the actual
values of VERIFY_{READ,WRITE} (not that they mattered, since nothing
really used it)
- microblaze used the type argument for a debug printout
but other than those oddities this should be a total no-op patch.
I tried to fix up all architectures, did fairly extensive grepping for
access_ok() uses, and the changes are trivial, but I may have missed
something. Any missed conversion should be trivially fixable, though.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-01-04 09:57:57 +07:00
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if (access_ok(to, n)) {
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2017-06-30 08:39:54 +07:00
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kasan_check_read(from, n);
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2017-03-21 08:56:06 +07:00
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n = raw_copy_to_user(to, from, n);
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2017-06-30 08:39:54 +07:00
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}
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2017-03-21 08:56:06 +07:00
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return n;
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}
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#else
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extern unsigned long
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_copy_to_user(void __user *, const void *, unsigned long);
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#endif
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static __always_inline unsigned long __must_check
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copy_from_user(void *to, const void __user *from, unsigned long n)
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{
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2017-06-30 08:42:43 +07:00
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if (likely(check_copy_size(to, n, false)))
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2017-03-21 08:56:06 +07:00
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n = _copy_from_user(to, from, n);
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return n;
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}
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static __always_inline unsigned long __must_check
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copy_to_user(void __user *to, const void *from, unsigned long n)
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{
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2017-06-30 08:42:43 +07:00
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if (likely(check_copy_size(from, n, true)))
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2017-03-21 08:56:06 +07:00
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n = _copy_to_user(to, from, n);
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return n;
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}
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#ifdef CONFIG_COMPAT
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static __always_inline unsigned long __must_check
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2017-08-24 05:29:10 +07:00
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copy_in_user(void __user *to, const void __user *from, unsigned long n)
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2017-03-21 08:56:06 +07:00
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{
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might_fault();
|
Remove 'type' argument from access_ok() function
Nobody has actually used the type (VERIFY_READ vs VERIFY_WRITE) argument
of the user address range verification function since we got rid of the
old racy i386-only code to walk page tables by hand.
It existed because the original 80386 would not honor the write protect
bit when in kernel mode, so you had to do COW by hand before doing any
user access. But we haven't supported that in a long time, and these
days the 'type' argument is a purely historical artifact.
A discussion about extending 'user_access_begin()' to do the range
checking resulted this patch, because there is no way we're going to
move the old VERIFY_xyz interface to that model. And it's best done at
the end of the merge window when I've done most of my merges, so let's
just get this done once and for all.
This patch was mostly done with a sed-script, with manual fix-ups for
the cases that weren't of the trivial 'access_ok(VERIFY_xyz' form.
There were a couple of notable cases:
- csky still had the old "verify_area()" name as an alias.
- the iter_iov code had magical hardcoded knowledge of the actual
values of VERIFY_{READ,WRITE} (not that they mattered, since nothing
really used it)
- microblaze used the type argument for a debug printout
but other than those oddities this should be a total no-op patch.
I tried to fix up all architectures, did fairly extensive grepping for
access_ok() uses, and the changes are trivial, but I may have missed
something. Any missed conversion should be trivially fixable, though.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-01-04 09:57:57 +07:00
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if (access_ok(to, n) && access_ok(from, n))
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2017-03-21 08:56:06 +07:00
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n = raw_copy_in_user(to, from, n);
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return n;
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}
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#endif
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2015-05-11 22:52:06 +07:00
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static __always_inline void pagefault_disabled_inc(void)
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{
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current->pagefault_disabled++;
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}
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static __always_inline void pagefault_disabled_dec(void)
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{
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current->pagefault_disabled--;
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}
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2006-12-07 11:32:20 +07:00
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/*
|
2015-05-11 22:52:06 +07:00
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* These routines enable/disable the pagefault handler. If disabled, it will
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* not take any locks and go straight to the fixup table.
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*
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2015-05-11 22:52:20 +07:00
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* User access methods will not sleep when called from a pagefault_disabled()
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* environment.
|
2006-12-07 11:32:20 +07:00
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*/
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static inline void pagefault_disable(void)
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{
|
2015-05-11 22:52:06 +07:00
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pagefault_disabled_inc();
|
2006-12-07 11:32:20 +07:00
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/*
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* make sure to have issued the store before a pagefault
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* can hit.
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*/
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barrier();
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}
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static inline void pagefault_enable(void)
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{
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/*
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* make sure to issue those last loads/stores before enabling
|
|
|
|
* the pagefault handler again.
|
|
|
|
*/
|
|
|
|
barrier();
|
2015-05-11 22:52:06 +07:00
|
|
|
pagefault_disabled_dec();
|
2006-12-07 11:32:20 +07:00
|
|
|
}
|
|
|
|
|
2015-05-11 22:52:06 +07:00
|
|
|
/*
|
|
|
|
* Is the pagefault handler disabled? If so, user access methods will not sleep.
|
|
|
|
*/
|
2019-05-15 12:38:06 +07:00
|
|
|
static inline bool pagefault_disabled(void)
|
|
|
|
{
|
|
|
|
return current->pagefault_disabled != 0;
|
|
|
|
}
|
2015-05-11 22:52:06 +07:00
|
|
|
|
2015-05-11 22:52:11 +07:00
|
|
|
/*
|
|
|
|
* The pagefault handler is in general disabled by pagefault_disable() or
|
|
|
|
* when in irq context (via in_atomic()).
|
|
|
|
*
|
|
|
|
* This function should only be used by the fault handlers. Other users should
|
|
|
|
* stick to pagefault_disabled().
|
|
|
|
* Please NEVER use preempt_disable() to disable the fault handler. With
|
|
|
|
* !CONFIG_PREEMPT_COUNT, this is like a NOP. So the handler won't be disabled.
|
|
|
|
* in_atomic() will report different values based on !CONFIG_PREEMPT_COUNT.
|
|
|
|
*/
|
|
|
|
#define faulthandler_disabled() (pagefault_disabled() || in_atomic())
|
|
|
|
|
2006-06-23 16:04:16 +07:00
|
|
|
#ifndef ARCH_HAS_NOCACHE_UACCESS
|
|
|
|
|
|
|
|
static inline unsigned long __copy_from_user_inatomic_nocache(void *to,
|
|
|
|
const void __user *from, unsigned long n)
|
|
|
|
{
|
|
|
|
return __copy_from_user_inatomic(to, from, n);
|
|
|
|
}
|
|
|
|
|
|
|
|
#endif /* ARCH_HAS_NOCACHE_UACCESS */
|
|
|
|
|
2008-04-18 01:05:36 +07:00
|
|
|
/*
|
|
|
|
* probe_kernel_read(): safely attempt to read from a location
|
|
|
|
* @dst: pointer to the buffer that shall take the data
|
|
|
|
* @src: address to read from
|
|
|
|
* @size: size of the data chunk
|
|
|
|
*
|
|
|
|
* Safely read from address @src to the buffer at @dst. If a kernel fault
|
|
|
|
* happens, handle that and return -EFAULT.
|
|
|
|
*/
|
2011-05-20 01:35:33 +07:00
|
|
|
extern long probe_kernel_read(void *dst, const void *src, size_t size);
|
|
|
|
extern long __probe_kernel_read(void *dst, const void *src, size_t size);
|
2008-04-18 01:05:36 +07:00
|
|
|
|
2019-05-15 12:38:18 +07:00
|
|
|
/*
|
|
|
|
* probe_user_read(): safely attempt to read from a location in user space
|
|
|
|
* @dst: pointer to the buffer that shall take the data
|
|
|
|
* @src: address to read from
|
|
|
|
* @size: size of the data chunk
|
|
|
|
*
|
|
|
|
* Safely read from address @src to the buffer at @dst. If a kernel fault
|
|
|
|
* happens, handle that and return -EFAULT.
|
|
|
|
*/
|
|
|
|
extern long probe_user_read(void *dst, const void __user *src, size_t size);
|
2019-05-22 15:27:44 +07:00
|
|
|
extern long __probe_user_read(void *dst, const void __user *src, size_t size);
|
2019-05-15 12:38:18 +07:00
|
|
|
|
2008-04-18 01:05:36 +07:00
|
|
|
/*
|
|
|
|
* probe_kernel_write(): safely attempt to write to a location
|
|
|
|
* @dst: address to write to
|
|
|
|
* @src: pointer to the data that shall be written
|
|
|
|
* @size: size of the data chunk
|
|
|
|
*
|
|
|
|
* Safely write to address @dst from the buffer at @src. If a kernel fault
|
|
|
|
* happens, handle that and return -EFAULT.
|
|
|
|
*/
|
2011-05-20 01:35:33 +07:00
|
|
|
extern long notrace probe_kernel_write(void *dst, const void *src, size_t size);
|
|
|
|
extern long notrace __probe_kernel_write(void *dst, const void *src, size_t size);
|
2008-04-18 01:05:36 +07:00
|
|
|
|
2015-08-29 05:56:22 +07:00
|
|
|
extern long strncpy_from_unsafe(char *dst, const void *unsafe_addr, long count);
|
2019-05-15 12:38:18 +07:00
|
|
|
extern long strncpy_from_unsafe_user(char *dst, const void __user *unsafe_addr,
|
|
|
|
long count);
|
|
|
|
extern long strnlen_unsafe_user(const void __user *unsafe_addr, long count);
|
2015-08-29 05:56:22 +07:00
|
|
|
|
2015-11-06 09:46:03 +07:00
|
|
|
/**
|
|
|
|
* probe_kernel_address(): safely attempt to read from a location
|
|
|
|
* @addr: address to read from
|
|
|
|
* @retval: read into this variable
|
|
|
|
*
|
|
|
|
* Returns 0 on success, or -EFAULT.
|
|
|
|
*/
|
|
|
|
#define probe_kernel_address(addr, retval) \
|
|
|
|
probe_kernel_read(&retval, addr, sizeof(retval))
|
|
|
|
|
2015-12-18 00:57:27 +07:00
|
|
|
#ifndef user_access_begin
|
2019-01-05 03:56:09 +07:00
|
|
|
#define user_access_begin(ptr,len) access_ok(ptr, len)
|
2015-12-18 00:57:27 +07:00
|
|
|
#define user_access_end() do { } while (0)
|
unsafe_[get|put]_user: change interface to use a error target label
When I initially added the unsafe_[get|put]_user() helpers in commit
5b24a7a2aa20 ("Add 'unsafe' user access functions for batched
accesses"), I made the mistake of modeling the interface on our
traditional __[get|put]_user() functions, which return zero on success,
or -EFAULT on failure.
That interface is fairly easy to use, but it's actually fairly nasty for
good code generation, since it essentially forces the caller to check
the error value for each access.
In particular, since the error handling is already internally
implemented with an exception handler, and we already use "asm goto" for
various other things, we could fairly easily make the error cases just
jump directly to an error label instead, and avoid the need for explicit
checking after each operation.
So switch the interface to pass in an error label, rather than checking
the error value in the caller. Best do it now before we start growing
more users (the signal handling code in particular would be a good place
to use the new interface).
So rather than
if (unsafe_get_user(x, ptr))
... handle error ..
the interface is now
unsafe_get_user(x, ptr, label);
where an error during the user mode fetch will now just cause a jump to
'label' in the caller.
Right now the actual _implementation_ of this all still ends up being a
"if (err) goto label", and does not take advantage of any exception
label tricks, but for "unsafe_put_user()" in particular it should be
fairly straightforward to convert to using the exception table model.
Note that "unsafe_get_user()" is much harder to convert to a clever
exception table model, because current versions of gcc do not allow the
use of "asm goto" (for the exception) with output values (for the actual
value to be fetched). But that is hopefully not a limitation in the
long term.
[ Also note that it might be a good idea to switch unsafe_get_user() to
actually _return_ the value it fetches from user space, but this
commit only changes the error handling semantics ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-09 03:02:01 +07:00
|
|
|
#define unsafe_get_user(x, ptr, err) do { if (unlikely(__get_user(x, ptr))) goto err; } while (0)
|
|
|
|
#define unsafe_put_user(x, ptr, err) do { if (unlikely(__put_user(x, ptr))) goto err; } while (0)
|
2019-04-03 14:39:48 +07:00
|
|
|
static inline unsigned long user_access_save(void) { return 0UL; }
|
|
|
|
static inline void user_access_restore(unsigned long flags) { }
|
2015-12-18 00:57:27 +07:00
|
|
|
#endif
|
|
|
|
|
2018-01-11 05:22:38 +07:00
|
|
|
#ifdef CONFIG_HARDENED_USERCOPY
|
2018-01-11 06:17:01 +07:00
|
|
|
void usercopy_warn(const char *name, const char *detail, bool to_user,
|
|
|
|
unsigned long offset, unsigned long len);
|
2018-01-11 05:22:38 +07:00
|
|
|
void __noreturn usercopy_abort(const char *name, const char *detail,
|
|
|
|
bool to_user, unsigned long offset,
|
|
|
|
unsigned long len);
|
|
|
|
#endif
|
|
|
|
|
2006-06-23 16:04:16 +07:00
|
|
|
#endif /* __LINUX_UACCESS_H__ */
|