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 22:07:57 +08:00
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/* SPDX-License-Identifier: GPL-2.0 */
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2008-10-23 13:26:29 +08:00
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#ifndef _ASM_X86_STRING_32_H
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#define _ASM_X86_STRING_32_H
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2005-04-17 06:20:36 +08:00
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#ifdef __KERNEL__
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2008-03-23 16:03:33 +08:00
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/* Let gcc decide whether to inline or use the out of line functions */
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2005-04-17 06:20:36 +08:00
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#define __HAVE_ARCH_STRCPY
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2007-07-21 23:09:59 +08:00
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extern char *strcpy(char *dest, const char *src);
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2005-04-17 06:20:36 +08:00
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#define __HAVE_ARCH_STRNCPY
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2007-07-21 23:09:59 +08:00
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extern char *strncpy(char *dest, const char *src, size_t count);
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2005-04-17 06:20:36 +08:00
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#define __HAVE_ARCH_STRCAT
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2007-07-21 23:09:59 +08:00
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extern char *strcat(char *dest, const char *src);
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2005-04-17 06:20:36 +08:00
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#define __HAVE_ARCH_STRNCAT
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2007-07-21 23:09:59 +08:00
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extern char *strncat(char *dest, const char *src, size_t count);
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2005-04-17 06:20:36 +08:00
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#define __HAVE_ARCH_STRCMP
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2007-07-21 23:09:59 +08:00
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extern int strcmp(const char *cs, const char *ct);
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2005-04-17 06:20:36 +08:00
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#define __HAVE_ARCH_STRNCMP
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2007-07-21 23:09:59 +08:00
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extern int strncmp(const char *cs, const char *ct, size_t count);
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2005-04-17 06:20:36 +08:00
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#define __HAVE_ARCH_STRCHR
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2007-07-21 23:09:59 +08:00
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extern char *strchr(const char *s, int c);
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2005-04-17 06:20:36 +08:00
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#define __HAVE_ARCH_STRLEN
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2007-07-21 23:09:59 +08:00
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extern size_t strlen(const char *s);
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2005-04-17 06:20:36 +08:00
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2008-05-12 21:44:39 +08:00
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static __always_inline void *__memcpy(void *to, const void *from, size_t n)
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2005-04-17 06:20:36 +08:00
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{
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2008-05-12 21:44:39 +08:00
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int d0, d1, d2;
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asm volatile("rep ; movsl\n\t"
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"movl %4,%%ecx\n\t"
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"andl $3,%%ecx\n\t"
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"jz 1f\n\t"
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"rep ; movsb\n\t"
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"1:"
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: "=&c" (d0), "=&D" (d1), "=&S" (d2)
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: "0" (n / 4), "g" (n), "1" ((long)to), "2" ((long)from)
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: "memory");
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return to;
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2005-04-17 06:20:36 +08:00
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}
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/*
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2005-05-01 23:58:48 +08:00
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* This looks ugly, but the compiler can optimize it totally,
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2005-04-17 06:20:36 +08:00
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* as the count is constant.
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*/
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2008-05-12 21:44:39 +08:00
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static __always_inline void *__constant_memcpy(void *to, const void *from,
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size_t n)
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2005-04-17 06:20:36 +08:00
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{
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2005-05-01 23:58:48 +08:00
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long esi, edi;
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2008-05-12 21:44:39 +08:00
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if (!n)
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return to;
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2005-05-01 23:58:48 +08:00
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switch (n) {
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2008-05-12 21:44:39 +08:00
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case 1:
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*(char *)to = *(char *)from;
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return to;
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case 2:
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*(short *)to = *(short *)from;
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return to;
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case 4:
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*(int *)to = *(int *)from;
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return to;
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case 3:
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*(short *)to = *(short *)from;
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*((char *)to + 2) = *((char *)from + 2);
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return to;
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case 5:
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*(int *)to = *(int *)from;
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*((char *)to + 4) = *((char *)from + 4);
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return to;
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case 6:
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*(int *)to = *(int *)from;
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*((short *)to + 2) = *((short *)from + 2);
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return to;
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case 8:
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*(int *)to = *(int *)from;
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*((int *)to + 1) = *((int *)from + 1);
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return to;
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2005-05-01 23:58:48 +08:00
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}
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2008-05-12 21:44:39 +08:00
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esi = (long)from;
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edi = (long)to;
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if (n >= 5 * 4) {
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2005-05-01 23:58:48 +08:00
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/* large block: use rep prefix */
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int ecx;
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2008-05-12 21:44:39 +08:00
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asm volatile("rep ; movsl"
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: "=&c" (ecx), "=&D" (edi), "=&S" (esi)
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: "0" (n / 4), "1" (edi), "2" (esi)
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: "memory"
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2005-05-01 23:58:48 +08:00
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);
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} else {
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/* small block: don't clobber ecx + smaller code */
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2008-05-12 21:44:39 +08:00
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if (n >= 4 * 4)
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asm volatile("movsl"
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: "=&D"(edi), "=&S"(esi)
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: "0"(edi), "1"(esi)
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: "memory");
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if (n >= 3 * 4)
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asm volatile("movsl"
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: "=&D"(edi), "=&S"(esi)
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: "0"(edi), "1"(esi)
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: "memory");
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if (n >= 2 * 4)
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asm volatile("movsl"
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: "=&D"(edi), "=&S"(esi)
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: "0"(edi), "1"(esi)
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: "memory");
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if (n >= 1 * 4)
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asm volatile("movsl"
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: "=&D"(edi), "=&S"(esi)
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: "0"(edi), "1"(esi)
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: "memory");
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2005-05-01 23:58:48 +08:00
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}
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2005-04-17 06:20:36 +08:00
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switch (n % 4) {
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2005-05-01 23:58:48 +08:00
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/* tail */
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2008-05-12 21:44:39 +08:00
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case 0:
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return to;
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case 1:
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asm volatile("movsb"
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: "=&D"(edi), "=&S"(esi)
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: "0"(edi), "1"(esi)
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: "memory");
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return to;
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case 2:
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asm volatile("movsw"
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: "=&D"(edi), "=&S"(esi)
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: "0"(edi), "1"(esi)
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: "memory");
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return to;
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default:
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asm volatile("movsw\n\tmovsb"
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: "=&D"(edi), "=&S"(esi)
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: "0"(edi), "1"(esi)
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: "memory");
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return to;
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2005-04-17 06:20:36 +08:00
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}
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}
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#define __HAVE_ARCH_MEMCPY
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include/linux/string.h: add the option of fortified string.h functions
This adds support for compiling with a rough equivalent to the glibc
_FORTIFY_SOURCE=1 feature, providing compile-time and runtime buffer
overflow checks for string.h functions when the compiler determines the
size of the source or destination buffer at compile-time. Unlike glibc,
it covers buffer reads in addition to writes.
GNU C __builtin_*_chk intrinsics are avoided because they would force a
much more complex implementation. They aren't designed to detect read
overflows and offer no real benefit when using an implementation based
on inline checks. Inline checks don't add up to much code size and
allow full use of the regular string intrinsics while avoiding the need
for a bunch of _chk functions and per-arch assembly to avoid wrapper
overhead.
This detects various overflows at compile-time in various drivers and
some non-x86 core kernel code. There will likely be issues caught in
regular use at runtime too.
Future improvements left out of initial implementation for simplicity,
as it's all quite optional and can be done incrementally:
* Some of the fortified string functions (strncpy, strcat), don't yet
place a limit on reads from the source based on __builtin_object_size of
the source buffer.
* Extending coverage to more string functions like strlcat.
* It should be possible to optionally use __builtin_object_size(x, 1) for
some functions (C strings) to detect intra-object overflows (like
glibc's _FORTIFY_SOURCE=2), but for now this takes the conservative
approach to avoid likely compatibility issues.
* The compile-time checks should be made available via a separate config
option which can be enabled by default (or always enabled) once enough
time has passed to get the issues it catches fixed.
Kees said:
"This is great to have. While it was out-of-tree code, it would have
blocked at least CVE-2016-3858 from being exploitable (improper size
argument to strlcpy()). I've sent a number of fixes for
out-of-bounds-reads that this detected upstream already"
[arnd@arndb.de: x86: fix fortified memcpy]
Link: http://lkml.kernel.org/r/20170627150047.660360-1-arnd@arndb.de
[keescook@chromium.org: avoid panic() in favor of BUG()]
Link: http://lkml.kernel.org/r/20170626235122.GA25261@beast
[keescook@chromium.org: move from -mm, add ARCH_HAS_FORTIFY_SOURCE, tweak Kconfig help]
Link: http://lkml.kernel.org/r/20170526095404.20439-1-danielmicay@gmail.com
Link: http://lkml.kernel.org/r/1497903987-21002-8-git-send-email-keescook@chromium.org
Signed-off-by: Daniel Micay <danielmicay@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Daniel Axtens <dja@axtens.net>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-13 05:36:10 +08:00
|
|
|
extern void *memcpy(void *, const void *, size_t);
|
2005-04-17 06:20:36 +08:00
|
|
|
|
include/linux/string.h: add the option of fortified string.h functions
This adds support for compiling with a rough equivalent to the glibc
_FORTIFY_SOURCE=1 feature, providing compile-time and runtime buffer
overflow checks for string.h functions when the compiler determines the
size of the source or destination buffer at compile-time. Unlike glibc,
it covers buffer reads in addition to writes.
GNU C __builtin_*_chk intrinsics are avoided because they would force a
much more complex implementation. They aren't designed to detect read
overflows and offer no real benefit when using an implementation based
on inline checks. Inline checks don't add up to much code size and
allow full use of the regular string intrinsics while avoiding the need
for a bunch of _chk functions and per-arch assembly to avoid wrapper
overhead.
This detects various overflows at compile-time in various drivers and
some non-x86 core kernel code. There will likely be issues caught in
regular use at runtime too.
Future improvements left out of initial implementation for simplicity,
as it's all quite optional and can be done incrementally:
* Some of the fortified string functions (strncpy, strcat), don't yet
place a limit on reads from the source based on __builtin_object_size of
the source buffer.
* Extending coverage to more string functions like strlcat.
* It should be possible to optionally use __builtin_object_size(x, 1) for
some functions (C strings) to detect intra-object overflows (like
glibc's _FORTIFY_SOURCE=2), but for now this takes the conservative
approach to avoid likely compatibility issues.
* The compile-time checks should be made available via a separate config
option which can be enabled by default (or always enabled) once enough
time has passed to get the issues it catches fixed.
Kees said:
"This is great to have. While it was out-of-tree code, it would have
blocked at least CVE-2016-3858 from being exploitable (improper size
argument to strlcpy()). I've sent a number of fixes for
out-of-bounds-reads that this detected upstream already"
[arnd@arndb.de: x86: fix fortified memcpy]
Link: http://lkml.kernel.org/r/20170627150047.660360-1-arnd@arndb.de
[keescook@chromium.org: avoid panic() in favor of BUG()]
Link: http://lkml.kernel.org/r/20170626235122.GA25261@beast
[keescook@chromium.org: move from -mm, add ARCH_HAS_FORTIFY_SOURCE, tweak Kconfig help]
Link: http://lkml.kernel.org/r/20170526095404.20439-1-danielmicay@gmail.com
Link: http://lkml.kernel.org/r/1497903987-21002-8-git-send-email-keescook@chromium.org
Signed-off-by: Daniel Micay <danielmicay@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Daniel Axtens <dja@axtens.net>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-13 05:36:10 +08:00
|
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#ifndef CONFIG_FORTIFY_SOURCE
|
2005-04-17 06:20:36 +08:00
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|
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#ifdef CONFIG_X86_USE_3DNOW
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#include <asm/mmx.h>
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/*
|
|
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|
* This CPU favours 3DNow strongly (eg AMD Athlon)
|
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|
*/
|
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|
2008-05-12 21:44:39 +08:00
|
|
|
static inline void *__constant_memcpy3d(void *to, const void *from, size_t len)
|
2005-04-17 06:20:36 +08:00
|
|
|
{
|
|
|
|
if (len < 512)
|
|
|
|
return __constant_memcpy(to, from, len);
|
|
|
|
return _mmx_memcpy(to, from, len);
|
|
|
|
}
|
|
|
|
|
2008-05-12 21:44:39 +08:00
|
|
|
static inline void *__memcpy3d(void *to, const void *from, size_t len)
|
2005-04-17 06:20:36 +08:00
|
|
|
{
|
|
|
|
if (len < 512)
|
|
|
|
return __memcpy(to, from, len);
|
|
|
|
return _mmx_memcpy(to, from, len);
|
|
|
|
}
|
|
|
|
|
2008-05-12 21:44:39 +08:00
|
|
|
#define memcpy(t, f, n) \
|
|
|
|
(__builtin_constant_p((n)) \
|
|
|
|
? __constant_memcpy3d((t), (f), (n)) \
|
|
|
|
: __memcpy3d((t), (f), (n)))
|
2005-04-17 06:20:36 +08:00
|
|
|
|
|
|
|
#else
|
|
|
|
|
|
|
|
/*
|
|
|
|
* No 3D Now!
|
|
|
|
*/
|
2008-05-12 21:44:39 +08:00
|
|
|
|
x86: Use __builtin_memset and __builtin_memcpy for memset/memcpy
GCC provides reasonable memset/memcpy functions itself, with __builtin_memset
and __builtin_memcpy. For the "unknown" cases, it'll fall back to our
current existing functions, but for fixed size versions it'll inline
something smart. Quite often that will be the same as we have now,
but sometimes it can do something smarter (for example, if the code
then sets the first member of a struct, it can do a shorter memset).
In addition, and this is more important, gcc knows which registers and
such are not clobbered (while for our asm version it pretty much
acts like a compiler barrier), so for various cases it can avoid reloading
values.
The effect on codesize is shown below on my typical laptop .config:
text data bss dec hex filename
5605675 2041100 6525148 14171923 d83f13 vmlinux.before
5595849 2041668 6525148 14162665 d81ae9 vmlinux.after
Due to some not-so-good behavior in the gcc 3.x series, this change
is only done for GCC 4.x and above.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
LKML-Reference: <20090928142122.6fc57e9c@infradead.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-09-28 20:21:22 +08:00
|
|
|
#if (__GNUC__ >= 4)
|
|
|
|
#define memcpy(t, f, n) __builtin_memcpy(t, f, n)
|
|
|
|
#else
|
2008-05-12 21:44:39 +08:00
|
|
|
#define memcpy(t, f, n) \
|
|
|
|
(__builtin_constant_p((n)) \
|
|
|
|
? __constant_memcpy((t), (f), (n)) \
|
|
|
|
: __memcpy((t), (f), (n)))
|
x86: Use __builtin_memset and __builtin_memcpy for memset/memcpy
GCC provides reasonable memset/memcpy functions itself, with __builtin_memset
and __builtin_memcpy. For the "unknown" cases, it'll fall back to our
current existing functions, but for fixed size versions it'll inline
something smart. Quite often that will be the same as we have now,
but sometimes it can do something smarter (for example, if the code
then sets the first member of a struct, it can do a shorter memset).
In addition, and this is more important, gcc knows which registers and
such are not clobbered (while for our asm version it pretty much
acts like a compiler barrier), so for various cases it can avoid reloading
values.
The effect on codesize is shown below on my typical laptop .config:
text data bss dec hex filename
5605675 2041100 6525148 14171923 d83f13 vmlinux.before
5595849 2041668 6525148 14162665 d81ae9 vmlinux.after
Due to some not-so-good behavior in the gcc 3.x series, this change
is only done for GCC 4.x and above.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
LKML-Reference: <20090928142122.6fc57e9c@infradead.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-09-28 20:21:22 +08:00
|
|
|
#endif
|
2005-04-17 06:20:36 +08:00
|
|
|
|
|
|
|
#endif
|
include/linux/string.h: add the option of fortified string.h functions
This adds support for compiling with a rough equivalent to the glibc
_FORTIFY_SOURCE=1 feature, providing compile-time and runtime buffer
overflow checks for string.h functions when the compiler determines the
size of the source or destination buffer at compile-time. Unlike glibc,
it covers buffer reads in addition to writes.
GNU C __builtin_*_chk intrinsics are avoided because they would force a
much more complex implementation. They aren't designed to detect read
overflows and offer no real benefit when using an implementation based
on inline checks. Inline checks don't add up to much code size and
allow full use of the regular string intrinsics while avoiding the need
for a bunch of _chk functions and per-arch assembly to avoid wrapper
overhead.
This detects various overflows at compile-time in various drivers and
some non-x86 core kernel code. There will likely be issues caught in
regular use at runtime too.
Future improvements left out of initial implementation for simplicity,
as it's all quite optional and can be done incrementally:
* Some of the fortified string functions (strncpy, strcat), don't yet
place a limit on reads from the source based on __builtin_object_size of
the source buffer.
* Extending coverage to more string functions like strlcat.
* It should be possible to optionally use __builtin_object_size(x, 1) for
some functions (C strings) to detect intra-object overflows (like
glibc's _FORTIFY_SOURCE=2), but for now this takes the conservative
approach to avoid likely compatibility issues.
* The compile-time checks should be made available via a separate config
option which can be enabled by default (or always enabled) once enough
time has passed to get the issues it catches fixed.
Kees said:
"This is great to have. While it was out-of-tree code, it would have
blocked at least CVE-2016-3858 from being exploitable (improper size
argument to strlcpy()). I've sent a number of fixes for
out-of-bounds-reads that this detected upstream already"
[arnd@arndb.de: x86: fix fortified memcpy]
Link: http://lkml.kernel.org/r/20170627150047.660360-1-arnd@arndb.de
[keescook@chromium.org: avoid panic() in favor of BUG()]
Link: http://lkml.kernel.org/r/20170626235122.GA25261@beast
[keescook@chromium.org: move from -mm, add ARCH_HAS_FORTIFY_SOURCE, tweak Kconfig help]
Link: http://lkml.kernel.org/r/20170526095404.20439-1-danielmicay@gmail.com
Link: http://lkml.kernel.org/r/1497903987-21002-8-git-send-email-keescook@chromium.org
Signed-off-by: Daniel Micay <danielmicay@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Daniel Axtens <dja@axtens.net>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-13 05:36:10 +08:00
|
|
|
#endif /* !CONFIG_FORTIFY_SOURCE */
|
2005-04-17 06:20:36 +08:00
|
|
|
|
|
|
|
#define __HAVE_ARCH_MEMMOVE
|
2008-05-12 21:44:39 +08:00
|
|
|
void *memmove(void *dest, const void *src, size_t n);
|
2005-04-17 06:20:36 +08:00
|
|
|
|
include/linux/string.h: add the option of fortified string.h functions
This adds support for compiling with a rough equivalent to the glibc
_FORTIFY_SOURCE=1 feature, providing compile-time and runtime buffer
overflow checks for string.h functions when the compiler determines the
size of the source or destination buffer at compile-time. Unlike glibc,
it covers buffer reads in addition to writes.
GNU C __builtin_*_chk intrinsics are avoided because they would force a
much more complex implementation. They aren't designed to detect read
overflows and offer no real benefit when using an implementation based
on inline checks. Inline checks don't add up to much code size and
allow full use of the regular string intrinsics while avoiding the need
for a bunch of _chk functions and per-arch assembly to avoid wrapper
overhead.
This detects various overflows at compile-time in various drivers and
some non-x86 core kernel code. There will likely be issues caught in
regular use at runtime too.
Future improvements left out of initial implementation for simplicity,
as it's all quite optional and can be done incrementally:
* Some of the fortified string functions (strncpy, strcat), don't yet
place a limit on reads from the source based on __builtin_object_size of
the source buffer.
* Extending coverage to more string functions like strlcat.
* It should be possible to optionally use __builtin_object_size(x, 1) for
some functions (C strings) to detect intra-object overflows (like
glibc's _FORTIFY_SOURCE=2), but for now this takes the conservative
approach to avoid likely compatibility issues.
* The compile-time checks should be made available via a separate config
option which can be enabled by default (or always enabled) once enough
time has passed to get the issues it catches fixed.
Kees said:
"This is great to have. While it was out-of-tree code, it would have
blocked at least CVE-2016-3858 from being exploitable (improper size
argument to strlcpy()). I've sent a number of fixes for
out-of-bounds-reads that this detected upstream already"
[arnd@arndb.de: x86: fix fortified memcpy]
Link: http://lkml.kernel.org/r/20170627150047.660360-1-arnd@arndb.de
[keescook@chromium.org: avoid panic() in favor of BUG()]
Link: http://lkml.kernel.org/r/20170626235122.GA25261@beast
[keescook@chromium.org: move from -mm, add ARCH_HAS_FORTIFY_SOURCE, tweak Kconfig help]
Link: http://lkml.kernel.org/r/20170526095404.20439-1-danielmicay@gmail.com
Link: http://lkml.kernel.org/r/1497903987-21002-8-git-send-email-keescook@chromium.org
Signed-off-by: Daniel Micay <danielmicay@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Daniel Axtens <dja@axtens.net>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-13 05:36:10 +08:00
|
|
|
extern int memcmp(const void *, const void *, size_t);
|
|
|
|
#ifndef CONFIG_FORTIFY_SOURCE
|
2005-04-17 06:20:36 +08:00
|
|
|
#define memcmp __builtin_memcmp
|
include/linux/string.h: add the option of fortified string.h functions
This adds support for compiling with a rough equivalent to the glibc
_FORTIFY_SOURCE=1 feature, providing compile-time and runtime buffer
overflow checks for string.h functions when the compiler determines the
size of the source or destination buffer at compile-time. Unlike glibc,
it covers buffer reads in addition to writes.
GNU C __builtin_*_chk intrinsics are avoided because they would force a
much more complex implementation. They aren't designed to detect read
overflows and offer no real benefit when using an implementation based
on inline checks. Inline checks don't add up to much code size and
allow full use of the regular string intrinsics while avoiding the need
for a bunch of _chk functions and per-arch assembly to avoid wrapper
overhead.
This detects various overflows at compile-time in various drivers and
some non-x86 core kernel code. There will likely be issues caught in
regular use at runtime too.
Future improvements left out of initial implementation for simplicity,
as it's all quite optional and can be done incrementally:
* Some of the fortified string functions (strncpy, strcat), don't yet
place a limit on reads from the source based on __builtin_object_size of
the source buffer.
* Extending coverage to more string functions like strlcat.
* It should be possible to optionally use __builtin_object_size(x, 1) for
some functions (C strings) to detect intra-object overflows (like
glibc's _FORTIFY_SOURCE=2), but for now this takes the conservative
approach to avoid likely compatibility issues.
* The compile-time checks should be made available via a separate config
option which can be enabled by default (or always enabled) once enough
time has passed to get the issues it catches fixed.
Kees said:
"This is great to have. While it was out-of-tree code, it would have
blocked at least CVE-2016-3858 from being exploitable (improper size
argument to strlcpy()). I've sent a number of fixes for
out-of-bounds-reads that this detected upstream already"
[arnd@arndb.de: x86: fix fortified memcpy]
Link: http://lkml.kernel.org/r/20170627150047.660360-1-arnd@arndb.de
[keescook@chromium.org: avoid panic() in favor of BUG()]
Link: http://lkml.kernel.org/r/20170626235122.GA25261@beast
[keescook@chromium.org: move from -mm, add ARCH_HAS_FORTIFY_SOURCE, tweak Kconfig help]
Link: http://lkml.kernel.org/r/20170526095404.20439-1-danielmicay@gmail.com
Link: http://lkml.kernel.org/r/1497903987-21002-8-git-send-email-keescook@chromium.org
Signed-off-by: Daniel Micay <danielmicay@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Daniel Axtens <dja@axtens.net>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-13 05:36:10 +08:00
|
|
|
#endif
|
2005-04-17 06:20:36 +08:00
|
|
|
|
|
|
|
#define __HAVE_ARCH_MEMCHR
|
2008-05-12 21:44:39 +08:00
|
|
|
extern void *memchr(const void *cs, int c, size_t count);
|
2005-04-17 06:20:36 +08:00
|
|
|
|
2008-05-12 21:44:39 +08:00
|
|
|
static inline void *__memset_generic(void *s, char c, size_t count)
|
2005-04-17 06:20:36 +08:00
|
|
|
{
|
2008-05-12 21:44:39 +08:00
|
|
|
int d0, d1;
|
|
|
|
asm volatile("rep\n\t"
|
|
|
|
"stosb"
|
|
|
|
: "=&c" (d0), "=&D" (d1)
|
|
|
|
: "a" (c), "1" (s), "0" (count)
|
|
|
|
: "memory");
|
|
|
|
return s;
|
2005-04-17 06:20:36 +08:00
|
|
|
}
|
|
|
|
|
|
|
|
/* we might want to write optimized versions of these later */
|
2008-05-12 21:44:39 +08:00
|
|
|
#define __constant_count_memset(s, c, count) __memset_generic((s), (c), (count))
|
2005-04-17 06:20:36 +08:00
|
|
|
|
|
|
|
/*
|
2008-05-12 21:44:39 +08:00
|
|
|
* memset(x, 0, y) is a reasonably common thing to do, so we want to fill
|
2005-04-17 06:20:36 +08:00
|
|
|
* things 32 bits at a time even when we don't know the size of the
|
|
|
|
* area at compile-time..
|
|
|
|
*/
|
2008-05-12 21:44:39 +08:00
|
|
|
static __always_inline
|
|
|
|
void *__constant_c_memset(void *s, unsigned long c, size_t count)
|
2005-04-17 06:20:36 +08:00
|
|
|
{
|
2008-05-12 21:44:39 +08:00
|
|
|
int d0, d1;
|
|
|
|
asm volatile("rep ; stosl\n\t"
|
|
|
|
"testb $2,%b3\n\t"
|
|
|
|
"je 1f\n\t"
|
|
|
|
"stosw\n"
|
|
|
|
"1:\ttestb $1,%b3\n\t"
|
|
|
|
"je 2f\n\t"
|
|
|
|
"stosb\n"
|
|
|
|
"2:"
|
|
|
|
: "=&c" (d0), "=&D" (d1)
|
|
|
|
: "a" (c), "q" (count), "0" (count/4), "1" ((long)s)
|
|
|
|
: "memory");
|
|
|
|
return s;
|
2005-04-17 06:20:36 +08:00
|
|
|
}
|
|
|
|
|
|
|
|
/* Added by Gertjan van Wingerde to make minix and sysv module work */
|
|
|
|
#define __HAVE_ARCH_STRNLEN
|
2008-05-12 21:44:39 +08:00
|
|
|
extern size_t strnlen(const char *s, size_t count);
|
2005-04-17 06:20:36 +08:00
|
|
|
/* end of additional stuff */
|
|
|
|
|
|
|
|
#define __HAVE_ARCH_STRSTR
|
|
|
|
extern char *strstr(const char *cs, const char *ct);
|
|
|
|
|
|
|
|
/*
|
|
|
|
* This looks horribly ugly, but the compiler can optimize it totally,
|
|
|
|
* as we by now know that both pattern and count is constant..
|
|
|
|
*/
|
2008-05-12 21:44:39 +08:00
|
|
|
static __always_inline
|
|
|
|
void *__constant_c_and_count_memset(void *s, unsigned long pattern,
|
|
|
|
size_t count)
|
2005-04-17 06:20:36 +08:00
|
|
|
{
|
|
|
|
switch (count) {
|
2008-05-12 21:44:39 +08:00
|
|
|
case 0:
|
|
|
|
return s;
|
|
|
|
case 1:
|
|
|
|
*(unsigned char *)s = pattern & 0xff;
|
|
|
|
return s;
|
|
|
|
case 2:
|
|
|
|
*(unsigned short *)s = pattern & 0xffff;
|
|
|
|
return s;
|
|
|
|
case 3:
|
|
|
|
*(unsigned short *)s = pattern & 0xffff;
|
|
|
|
*((unsigned char *)s + 2) = pattern & 0xff;
|
|
|
|
return s;
|
|
|
|
case 4:
|
|
|
|
*(unsigned long *)s = pattern;
|
|
|
|
return s;
|
|
|
|
}
|
|
|
|
|
|
|
|
#define COMMON(x) \
|
|
|
|
asm volatile("rep ; stosl" \
|
|
|
|
x \
|
|
|
|
: "=&c" (d0), "=&D" (d1) \
|
2008-05-27 04:36:53 +08:00
|
|
|
: "a" (eax), "0" (count/4), "1" ((long)s) \
|
2008-05-12 21:44:39 +08:00
|
|
|
: "memory")
|
|
|
|
|
|
|
|
{
|
|
|
|
int d0, d1;
|
2008-05-27 04:36:53 +08:00
|
|
|
#if __GNUC__ == 4 && __GNUC_MINOR__ == 0
|
|
|
|
/* Workaround for broken gcc 4.0 */
|
|
|
|
register unsigned long eax asm("%eax") = pattern;
|
|
|
|
#else
|
|
|
|
unsigned long eax = pattern;
|
|
|
|
#endif
|
|
|
|
|
2008-05-12 21:44:39 +08:00
|
|
|
switch (count % 4) {
|
2005-04-17 06:20:36 +08:00
|
|
|
case 0:
|
2008-05-12 21:44:39 +08:00
|
|
|
COMMON("");
|
2005-04-17 06:20:36 +08:00
|
|
|
return s;
|
|
|
|
case 1:
|
2008-05-12 21:44:39 +08:00
|
|
|
COMMON("\n\tstosb");
|
2005-04-17 06:20:36 +08:00
|
|
|
return s;
|
|
|
|
case 2:
|
2008-05-12 21:44:39 +08:00
|
|
|
COMMON("\n\tstosw");
|
2005-04-17 06:20:36 +08:00
|
|
|
return s;
|
2008-05-12 21:44:39 +08:00
|
|
|
default:
|
|
|
|
COMMON("\n\tstosw\n\tstosb");
|
2005-04-17 06:20:36 +08:00
|
|
|
return s;
|
2008-05-12 21:44:39 +08:00
|
|
|
}
|
2005-04-17 06:20:36 +08:00
|
|
|
}
|
2008-05-12 21:44:39 +08:00
|
|
|
|
2005-04-17 06:20:36 +08:00
|
|
|
#undef COMMON
|
|
|
|
}
|
|
|
|
|
2008-05-12 21:44:39 +08:00
|
|
|
#define __constant_c_x_memset(s, c, count) \
|
|
|
|
(__builtin_constant_p(count) \
|
|
|
|
? __constant_c_and_count_memset((s), (c), (count)) \
|
|
|
|
: __constant_c_memset((s), (c), (count)))
|
2005-04-17 06:20:36 +08:00
|
|
|
|
2008-05-12 21:44:39 +08:00
|
|
|
#define __memset(s, c, count) \
|
|
|
|
(__builtin_constant_p(count) \
|
|
|
|
? __constant_count_memset((s), (c), (count)) \
|
|
|
|
: __memset_generic((s), (c), (count)))
|
2005-04-17 06:20:36 +08:00
|
|
|
|
|
|
|
#define __HAVE_ARCH_MEMSET
|
include/linux/string.h: add the option of fortified string.h functions
This adds support for compiling with a rough equivalent to the glibc
_FORTIFY_SOURCE=1 feature, providing compile-time and runtime buffer
overflow checks for string.h functions when the compiler determines the
size of the source or destination buffer at compile-time. Unlike glibc,
it covers buffer reads in addition to writes.
GNU C __builtin_*_chk intrinsics are avoided because they would force a
much more complex implementation. They aren't designed to detect read
overflows and offer no real benefit when using an implementation based
on inline checks. Inline checks don't add up to much code size and
allow full use of the regular string intrinsics while avoiding the need
for a bunch of _chk functions and per-arch assembly to avoid wrapper
overhead.
This detects various overflows at compile-time in various drivers and
some non-x86 core kernel code. There will likely be issues caught in
regular use at runtime too.
Future improvements left out of initial implementation for simplicity,
as it's all quite optional and can be done incrementally:
* Some of the fortified string functions (strncpy, strcat), don't yet
place a limit on reads from the source based on __builtin_object_size of
the source buffer.
* Extending coverage to more string functions like strlcat.
* It should be possible to optionally use __builtin_object_size(x, 1) for
some functions (C strings) to detect intra-object overflows (like
glibc's _FORTIFY_SOURCE=2), but for now this takes the conservative
approach to avoid likely compatibility issues.
* The compile-time checks should be made available via a separate config
option which can be enabled by default (or always enabled) once enough
time has passed to get the issues it catches fixed.
Kees said:
"This is great to have. While it was out-of-tree code, it would have
blocked at least CVE-2016-3858 from being exploitable (improper size
argument to strlcpy()). I've sent a number of fixes for
out-of-bounds-reads that this detected upstream already"
[arnd@arndb.de: x86: fix fortified memcpy]
Link: http://lkml.kernel.org/r/20170627150047.660360-1-arnd@arndb.de
[keescook@chromium.org: avoid panic() in favor of BUG()]
Link: http://lkml.kernel.org/r/20170626235122.GA25261@beast
[keescook@chromium.org: move from -mm, add ARCH_HAS_FORTIFY_SOURCE, tweak Kconfig help]
Link: http://lkml.kernel.org/r/20170526095404.20439-1-danielmicay@gmail.com
Link: http://lkml.kernel.org/r/1497903987-21002-8-git-send-email-keescook@chromium.org
Signed-off-by: Daniel Micay <danielmicay@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Daniel Axtens <dja@axtens.net>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-13 05:36:10 +08:00
|
|
|
extern void *memset(void *, int, size_t);
|
|
|
|
#ifndef CONFIG_FORTIFY_SOURCE
|
x86: Use __builtin_memset and __builtin_memcpy for memset/memcpy
GCC provides reasonable memset/memcpy functions itself, with __builtin_memset
and __builtin_memcpy. For the "unknown" cases, it'll fall back to our
current existing functions, but for fixed size versions it'll inline
something smart. Quite often that will be the same as we have now,
but sometimes it can do something smarter (for example, if the code
then sets the first member of a struct, it can do a shorter memset).
In addition, and this is more important, gcc knows which registers and
such are not clobbered (while for our asm version it pretty much
acts like a compiler barrier), so for various cases it can avoid reloading
values.
The effect on codesize is shown below on my typical laptop .config:
text data bss dec hex filename
5605675 2041100 6525148 14171923 d83f13 vmlinux.before
5595849 2041668 6525148 14162665 d81ae9 vmlinux.after
Due to some not-so-good behavior in the gcc 3.x series, this change
is only done for GCC 4.x and above.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
LKML-Reference: <20090928142122.6fc57e9c@infradead.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-09-28 20:21:22 +08:00
|
|
|
#if (__GNUC__ >= 4)
|
|
|
|
#define memset(s, c, count) __builtin_memset(s, c, count)
|
|
|
|
#else
|
2008-05-12 21:44:39 +08:00
|
|
|
#define memset(s, c, count) \
|
|
|
|
(__builtin_constant_p(c) \
|
|
|
|
? __constant_c_x_memset((s), (0x01010101UL * (unsigned char)(c)), \
|
|
|
|
(count)) \
|
|
|
|
: __memset((s), (c), (count)))
|
x86: Use __builtin_memset and __builtin_memcpy for memset/memcpy
GCC provides reasonable memset/memcpy functions itself, with __builtin_memset
and __builtin_memcpy. For the "unknown" cases, it'll fall back to our
current existing functions, but for fixed size versions it'll inline
something smart. Quite often that will be the same as we have now,
but sometimes it can do something smarter (for example, if the code
then sets the first member of a struct, it can do a shorter memset).
In addition, and this is more important, gcc knows which registers and
such are not clobbered (while for our asm version it pretty much
acts like a compiler barrier), so for various cases it can avoid reloading
values.
The effect on codesize is shown below on my typical laptop .config:
text data bss dec hex filename
5605675 2041100 6525148 14171923 d83f13 vmlinux.before
5595849 2041668 6525148 14162665 d81ae9 vmlinux.after
Due to some not-so-good behavior in the gcc 3.x series, this change
is only done for GCC 4.x and above.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
LKML-Reference: <20090928142122.6fc57e9c@infradead.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-09-28 20:21:22 +08:00
|
|
|
#endif
|
include/linux/string.h: add the option of fortified string.h functions
This adds support for compiling with a rough equivalent to the glibc
_FORTIFY_SOURCE=1 feature, providing compile-time and runtime buffer
overflow checks for string.h functions when the compiler determines the
size of the source or destination buffer at compile-time. Unlike glibc,
it covers buffer reads in addition to writes.
GNU C __builtin_*_chk intrinsics are avoided because they would force a
much more complex implementation. They aren't designed to detect read
overflows and offer no real benefit when using an implementation based
on inline checks. Inline checks don't add up to much code size and
allow full use of the regular string intrinsics while avoiding the need
for a bunch of _chk functions and per-arch assembly to avoid wrapper
overhead.
This detects various overflows at compile-time in various drivers and
some non-x86 core kernel code. There will likely be issues caught in
regular use at runtime too.
Future improvements left out of initial implementation for simplicity,
as it's all quite optional and can be done incrementally:
* Some of the fortified string functions (strncpy, strcat), don't yet
place a limit on reads from the source based on __builtin_object_size of
the source buffer.
* Extending coverage to more string functions like strlcat.
* It should be possible to optionally use __builtin_object_size(x, 1) for
some functions (C strings) to detect intra-object overflows (like
glibc's _FORTIFY_SOURCE=2), but for now this takes the conservative
approach to avoid likely compatibility issues.
* The compile-time checks should be made available via a separate config
option which can be enabled by default (or always enabled) once enough
time has passed to get the issues it catches fixed.
Kees said:
"This is great to have. While it was out-of-tree code, it would have
blocked at least CVE-2016-3858 from being exploitable (improper size
argument to strlcpy()). I've sent a number of fixes for
out-of-bounds-reads that this detected upstream already"
[arnd@arndb.de: x86: fix fortified memcpy]
Link: http://lkml.kernel.org/r/20170627150047.660360-1-arnd@arndb.de
[keescook@chromium.org: avoid panic() in favor of BUG()]
Link: http://lkml.kernel.org/r/20170626235122.GA25261@beast
[keescook@chromium.org: move from -mm, add ARCH_HAS_FORTIFY_SOURCE, tweak Kconfig help]
Link: http://lkml.kernel.org/r/20170526095404.20439-1-danielmicay@gmail.com
Link: http://lkml.kernel.org/r/1497903987-21002-8-git-send-email-keescook@chromium.org
Signed-off-by: Daniel Micay <danielmicay@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Daniel Axtens <dja@axtens.net>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-13 05:36:10 +08:00
|
|
|
#endif /* !CONFIG_FORTIFY_SOURCE */
|
2005-04-17 06:20:36 +08:00
|
|
|
|
2017-09-09 07:13:56 +08:00
|
|
|
#define __HAVE_ARCH_MEMSET16
|
|
|
|
static inline void *memset16(uint16_t *s, uint16_t v, size_t n)
|
|
|
|
{
|
|
|
|
int d0, d1;
|
|
|
|
asm volatile("rep\n\t"
|
|
|
|
"stosw"
|
|
|
|
: "=&c" (d0), "=&D" (d1)
|
|
|
|
: "a" (v), "1" (s), "0" (n)
|
|
|
|
: "memory");
|
|
|
|
return s;
|
|
|
|
}
|
|
|
|
|
|
|
|
#define __HAVE_ARCH_MEMSET32
|
|
|
|
static inline void *memset32(uint32_t *s, uint32_t v, size_t n)
|
|
|
|
{
|
|
|
|
int d0, d1;
|
|
|
|
asm volatile("rep\n\t"
|
|
|
|
"stosl"
|
|
|
|
: "=&c" (d0), "=&D" (d1)
|
|
|
|
: "a" (v), "1" (s), "0" (n)
|
|
|
|
: "memory");
|
|
|
|
return s;
|
|
|
|
}
|
|
|
|
|
2005-04-17 06:20:36 +08:00
|
|
|
/*
|
|
|
|
* find the first occurrence of byte 'c', or 1 past the area if none
|
|
|
|
*/
|
|
|
|
#define __HAVE_ARCH_MEMSCAN
|
2008-05-12 21:44:39 +08:00
|
|
|
extern void *memscan(void *addr, int c, size_t size);
|
2005-04-17 06:20:36 +08:00
|
|
|
|
|
|
|
#endif /* __KERNEL__ */
|
|
|
|
|
2008-10-23 13:26:29 +08:00
|
|
|
#endif /* _ASM_X86_STRING_32_H */
|