linux-stable/arch/x86/entry/syscall_64.c

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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 14:07:57 +00:00
// SPDX-License-Identifier: GPL-2.0
/* System call table for x86-64. */
#include <linux/linkage.h>
#include <linux/sys.h>
#include <linux/cache.h>
#include <asm/asm-offsets.h>
#include <asm/syscall.h>
syscalls/x86: Use 'struct pt_regs' based syscall calling convention for 64-bit syscalls Let's make use of ARCH_HAS_SYSCALL_WRAPPER=y on pure 64-bit x86-64 systems: Each syscall defines a stub which takes struct pt_regs as its only argument. It decodes just those parameters it needs, e.g: asmlinkage long sys_xyzzy(const struct pt_regs *regs) { return SyS_xyzzy(regs->di, regs->si, regs->dx); } This approach avoids leaking random user-provided register content down the call chain. For example, for sys_recv() which is a 4-parameter syscall, the assembly now is (in slightly reordered fashion): <sys_recv>: callq <__fentry__> /* decode regs->di, ->si, ->dx and ->r10 */ mov 0x70(%rdi),%rdi mov 0x68(%rdi),%rsi mov 0x60(%rdi),%rdx mov 0x38(%rdi),%rcx [ SyS_recv() is automatically inlined by the compiler, as it is not [yet] used anywhere else ] /* clear %r9 and %r8, the 5th and 6th args */ xor %r9d,%r9d xor %r8d,%r8d /* do the actual work */ callq __sys_recvfrom /* cleanup and return */ cltq retq The only valid place in an x86-64 kernel which rightfully calls a syscall function on its own -- vsyscall -- needs to be modified to pass struct pt_regs onwards as well. To keep the syscall table generation working independent of SYSCALL_PTREGS being enabled, the stubs are named the same as the "original" syscall stubs, i.e. sys_*(). This patch is based on an original proof-of-concept | From: Linus Torvalds <torvalds@linux-foundation.org> | Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> and was split up and heavily modified by me, in particular to base it on ARCH_HAS_SYSCALL_WRAPPER, to limit it to 64-bit-only for the time being, and to update the vsyscall to the new calling convention. Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20180405095307.3730-4-linux@dominikbrodowski.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-04-05 09:53:02 +00:00
/* this is a lie, but it does not hurt as sys_ni_syscall just returns -EINVAL */
extern asmlinkage long sys_ni_syscall(const struct pt_regs *);
#define __SYSCALL_64(nr, sym, qual) extern asmlinkage long sym(const struct pt_regs *);
x86/syscalls: Split the x32 syscalls into their own table For unfortunate historical reasons, the x32 syscalls and the x86_64 syscalls are not all numbered the same. As an example, ioctl() is nr 16 on x86_64 but 514 on x32. This has potentially nasty consequences, since it means that there are two valid RAX values to do ioctl(2) and two invalid RAX values. The valid values are 16 (i.e. ioctl(2) using the x86_64 ABI) and (514 | 0x40000000) (i.e. ioctl(2) using the x32 ABI). The invalid values are 514 and (16 | 0x40000000). 514 will enter the "COMPAT_SYSCALL_DEFINE3(ioctl, ...)" entry point with in_compat_syscall() and in_x32_syscall() returning false, whereas (16 | 0x40000000) will enter the native entry point with in_compat_syscall() and in_x32_syscall() returning true. Both are bogus, and both will exercise code paths in the kernel and in any running seccomp filters that really ought to be unreachable. Splitting out the x32 syscalls into their own tables, allows both bogus invocations to return -ENOSYS. I've checked glibc, musl, and Bionic, and all of them appear to call syscalls with their correct numbers, so this change should have no effect on them. There is an added benefit going forward: new syscalls that need special handling on x32 can share the same number on x32 and x86_64. This means that the special syscall range 512-547 can be treated as a legacy wart instead of something that may need to be extended in the future. Also add a selftest to verify the new behavior. Signed-off-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/208024256b764312598f014ebfb0a42472c19354.1562185330.git.luto@kernel.org
2019-07-03 20:34:04 +00:00
#define __SYSCALL_X32(nr, sym, qual) __SYSCALL_64(nr, sym, qual)
#include <asm/syscalls_64.h>
#undef __SYSCALL_64
x86/syscalls: Split the x32 syscalls into their own table For unfortunate historical reasons, the x32 syscalls and the x86_64 syscalls are not all numbered the same. As an example, ioctl() is nr 16 on x86_64 but 514 on x32. This has potentially nasty consequences, since it means that there are two valid RAX values to do ioctl(2) and two invalid RAX values. The valid values are 16 (i.e. ioctl(2) using the x86_64 ABI) and (514 | 0x40000000) (i.e. ioctl(2) using the x32 ABI). The invalid values are 514 and (16 | 0x40000000). 514 will enter the "COMPAT_SYSCALL_DEFINE3(ioctl, ...)" entry point with in_compat_syscall() and in_x32_syscall() returning false, whereas (16 | 0x40000000) will enter the native entry point with in_compat_syscall() and in_x32_syscall() returning true. Both are bogus, and both will exercise code paths in the kernel and in any running seccomp filters that really ought to be unreachable. Splitting out the x32 syscalls into their own tables, allows both bogus invocations to return -ENOSYS. I've checked glibc, musl, and Bionic, and all of them appear to call syscalls with their correct numbers, so this change should have no effect on them. There is an added benefit going forward: new syscalls that need special handling on x32 can share the same number on x32 and x86_64. This means that the special syscall range 512-547 can be treated as a legacy wart instead of something that may need to be extended in the future. Also add a selftest to verify the new behavior. Signed-off-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/208024256b764312598f014ebfb0a42472c19354.1562185330.git.luto@kernel.org
2019-07-03 20:34:04 +00:00
#undef __SYSCALL_X32
#define __SYSCALL_64(nr, sym, qual) [nr] = sym,
x86/syscalls: Split the x32 syscalls into their own table For unfortunate historical reasons, the x32 syscalls and the x86_64 syscalls are not all numbered the same. As an example, ioctl() is nr 16 on x86_64 but 514 on x32. This has potentially nasty consequences, since it means that there are two valid RAX values to do ioctl(2) and two invalid RAX values. The valid values are 16 (i.e. ioctl(2) using the x86_64 ABI) and (514 | 0x40000000) (i.e. ioctl(2) using the x32 ABI). The invalid values are 514 and (16 | 0x40000000). 514 will enter the "COMPAT_SYSCALL_DEFINE3(ioctl, ...)" entry point with in_compat_syscall() and in_x32_syscall() returning false, whereas (16 | 0x40000000) will enter the native entry point with in_compat_syscall() and in_x32_syscall() returning true. Both are bogus, and both will exercise code paths in the kernel and in any running seccomp filters that really ought to be unreachable. Splitting out the x32 syscalls into their own tables, allows both bogus invocations to return -ENOSYS. I've checked glibc, musl, and Bionic, and all of them appear to call syscalls with their correct numbers, so this change should have no effect on them. There is an added benefit going forward: new syscalls that need special handling on x32 can share the same number on x32 and x86_64. This means that the special syscall range 512-547 can be treated as a legacy wart instead of something that may need to be extended in the future. Also add a selftest to verify the new behavior. Signed-off-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/208024256b764312598f014ebfb0a42472c19354.1562185330.git.luto@kernel.org
2019-07-03 20:34:04 +00:00
#define __SYSCALL_X32(nr, sym, qual)
asmlinkage const sys_call_ptr_t sys_call_table[__NR_syscall_max+1] = {
/*
* Smells like a compiler bug -- it doesn't work
* when the & below is removed.
*/
[0 ... __NR_syscall_max] = &sys_ni_syscall,
#include <asm/syscalls_64.h>
};
x86/syscalls: Split the x32 syscalls into their own table For unfortunate historical reasons, the x32 syscalls and the x86_64 syscalls are not all numbered the same. As an example, ioctl() is nr 16 on x86_64 but 514 on x32. This has potentially nasty consequences, since it means that there are two valid RAX values to do ioctl(2) and two invalid RAX values. The valid values are 16 (i.e. ioctl(2) using the x86_64 ABI) and (514 | 0x40000000) (i.e. ioctl(2) using the x32 ABI). The invalid values are 514 and (16 | 0x40000000). 514 will enter the "COMPAT_SYSCALL_DEFINE3(ioctl, ...)" entry point with in_compat_syscall() and in_x32_syscall() returning false, whereas (16 | 0x40000000) will enter the native entry point with in_compat_syscall() and in_x32_syscall() returning true. Both are bogus, and both will exercise code paths in the kernel and in any running seccomp filters that really ought to be unreachable. Splitting out the x32 syscalls into their own tables, allows both bogus invocations to return -ENOSYS. I've checked glibc, musl, and Bionic, and all of them appear to call syscalls with their correct numbers, so this change should have no effect on them. There is an added benefit going forward: new syscalls that need special handling on x32 can share the same number on x32 and x86_64. This means that the special syscall range 512-547 can be treated as a legacy wart instead of something that may need to be extended in the future. Also add a selftest to verify the new behavior. Signed-off-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/208024256b764312598f014ebfb0a42472c19354.1562185330.git.luto@kernel.org
2019-07-03 20:34:04 +00:00
#undef __SYSCALL_64
#undef __SYSCALL_X32
#ifdef CONFIG_X86_X32_ABI
#define __SYSCALL_64(nr, sym, qual)
#define __SYSCALL_X32(nr, sym, qual) [nr] = sym,
asmlinkage const sys_call_ptr_t x32_sys_call_table[__NR_syscall_x32_max+1] = {
/*
* Smells like a compiler bug -- it doesn't work
* when the & below is removed.
*/
[0 ... __NR_syscall_x32_max] = &sys_ni_syscall,
#include <asm/syscalls_64.h>
};
#undef __SYSCALL_64
#undef __SYSCALL_X32
#endif