mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-16 17:36:57 +07:00
b24413180f
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>
238 lines
6.1 KiB
C
238 lines
6.1 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
/*
|
|
* x86 single-step support code, common to 32-bit and 64-bit.
|
|
*/
|
|
#include <linux/sched.h>
|
|
#include <linux/sched/task_stack.h>
|
|
#include <linux/mm.h>
|
|
#include <linux/ptrace.h>
|
|
#include <asm/desc.h>
|
|
#include <asm/mmu_context.h>
|
|
|
|
unsigned long convert_ip_to_linear(struct task_struct *child, struct pt_regs *regs)
|
|
{
|
|
unsigned long addr, seg;
|
|
|
|
addr = regs->ip;
|
|
seg = regs->cs;
|
|
if (v8086_mode(regs)) {
|
|
addr = (addr & 0xffff) + (seg << 4);
|
|
return addr;
|
|
}
|
|
|
|
#ifdef CONFIG_MODIFY_LDT_SYSCALL
|
|
/*
|
|
* We'll assume that the code segments in the GDT
|
|
* are all zero-based. That is largely true: the
|
|
* TLS segments are used for data, and the PNPBIOS
|
|
* and APM bios ones we just ignore here.
|
|
*/
|
|
if ((seg & SEGMENT_TI_MASK) == SEGMENT_LDT) {
|
|
struct desc_struct *desc;
|
|
unsigned long base;
|
|
|
|
seg >>= 3;
|
|
|
|
mutex_lock(&child->mm->context.lock);
|
|
if (unlikely(!child->mm->context.ldt ||
|
|
seg >= child->mm->context.ldt->nr_entries))
|
|
addr = -1L; /* bogus selector, access would fault */
|
|
else {
|
|
desc = &child->mm->context.ldt->entries[seg];
|
|
base = get_desc_base(desc);
|
|
|
|
/* 16-bit code segment? */
|
|
if (!desc->d)
|
|
addr &= 0xffff;
|
|
addr += base;
|
|
}
|
|
mutex_unlock(&child->mm->context.lock);
|
|
}
|
|
#endif
|
|
|
|
return addr;
|
|
}
|
|
|
|
static int is_setting_trap_flag(struct task_struct *child, struct pt_regs *regs)
|
|
{
|
|
int i, copied;
|
|
unsigned char opcode[15];
|
|
unsigned long addr = convert_ip_to_linear(child, regs);
|
|
|
|
copied = access_process_vm(child, addr, opcode, sizeof(opcode),
|
|
FOLL_FORCE);
|
|
for (i = 0; i < copied; i++) {
|
|
switch (opcode[i]) {
|
|
/* popf and iret */
|
|
case 0x9d: case 0xcf:
|
|
return 1;
|
|
|
|
/* CHECKME: 64 65 */
|
|
|
|
/* opcode and address size prefixes */
|
|
case 0x66: case 0x67:
|
|
continue;
|
|
/* irrelevant prefixes (segment overrides and repeats) */
|
|
case 0x26: case 0x2e:
|
|
case 0x36: case 0x3e:
|
|
case 0x64: case 0x65:
|
|
case 0xf0: case 0xf2: case 0xf3:
|
|
continue;
|
|
|
|
#ifdef CONFIG_X86_64
|
|
case 0x40 ... 0x4f:
|
|
if (!user_64bit_mode(regs))
|
|
/* 32-bit mode: register increment */
|
|
return 0;
|
|
/* 64-bit mode: REX prefix */
|
|
continue;
|
|
#endif
|
|
|
|
/* CHECKME: f2, f3 */
|
|
|
|
/*
|
|
* pushf: NOTE! We should probably not let
|
|
* the user see the TF bit being set. But
|
|
* it's more pain than it's worth to avoid
|
|
* it, and a debugger could emulate this
|
|
* all in user space if it _really_ cares.
|
|
*/
|
|
case 0x9c:
|
|
default:
|
|
return 0;
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Enable single-stepping. Return nonzero if user mode is not using TF itself.
|
|
*/
|
|
static int enable_single_step(struct task_struct *child)
|
|
{
|
|
struct pt_regs *regs = task_pt_regs(child);
|
|
unsigned long oflags;
|
|
|
|
/*
|
|
* If we stepped into a sysenter/syscall insn, it trapped in
|
|
* kernel mode; do_debug() cleared TF and set TIF_SINGLESTEP.
|
|
* If user-mode had set TF itself, then it's still clear from
|
|
* do_debug() and we need to set it again to restore the user
|
|
* state so we don't wrongly set TIF_FORCED_TF below.
|
|
* If enable_single_step() was used last and that is what
|
|
* set TIF_SINGLESTEP, then both TF and TIF_FORCED_TF are
|
|
* already set and our bookkeeping is fine.
|
|
*/
|
|
if (unlikely(test_tsk_thread_flag(child, TIF_SINGLESTEP)))
|
|
regs->flags |= X86_EFLAGS_TF;
|
|
|
|
/*
|
|
* Always set TIF_SINGLESTEP - this guarantees that
|
|
* we single-step system calls etc.. This will also
|
|
* cause us to set TF when returning to user mode.
|
|
*/
|
|
set_tsk_thread_flag(child, TIF_SINGLESTEP);
|
|
|
|
oflags = regs->flags;
|
|
|
|
/* Set TF on the kernel stack.. */
|
|
regs->flags |= X86_EFLAGS_TF;
|
|
|
|
/*
|
|
* ..but if TF is changed by the instruction we will trace,
|
|
* don't mark it as being "us" that set it, so that we
|
|
* won't clear it by hand later.
|
|
*
|
|
* Note that if we don't actually execute the popf because
|
|
* of a signal arriving right now or suchlike, we will lose
|
|
* track of the fact that it really was "us" that set it.
|
|
*/
|
|
if (is_setting_trap_flag(child, regs)) {
|
|
clear_tsk_thread_flag(child, TIF_FORCED_TF);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* If TF was already set, check whether it was us who set it.
|
|
* If not, we should never attempt a block step.
|
|
*/
|
|
if (oflags & X86_EFLAGS_TF)
|
|
return test_tsk_thread_flag(child, TIF_FORCED_TF);
|
|
|
|
set_tsk_thread_flag(child, TIF_FORCED_TF);
|
|
|
|
return 1;
|
|
}
|
|
|
|
void set_task_blockstep(struct task_struct *task, bool on)
|
|
{
|
|
unsigned long debugctl;
|
|
|
|
/*
|
|
* Ensure irq/preemption can't change debugctl in between.
|
|
* Note also that both TIF_BLOCKSTEP and debugctl should
|
|
* be changed atomically wrt preemption.
|
|
*
|
|
* NOTE: this means that set/clear TIF_BLOCKSTEP is only safe if
|
|
* task is current or it can't be running, otherwise we can race
|
|
* with __switch_to_xtra(). We rely on ptrace_freeze_traced() but
|
|
* PTRACE_KILL is not safe.
|
|
*/
|
|
local_irq_disable();
|
|
debugctl = get_debugctlmsr();
|
|
if (on) {
|
|
debugctl |= DEBUGCTLMSR_BTF;
|
|
set_tsk_thread_flag(task, TIF_BLOCKSTEP);
|
|
} else {
|
|
debugctl &= ~DEBUGCTLMSR_BTF;
|
|
clear_tsk_thread_flag(task, TIF_BLOCKSTEP);
|
|
}
|
|
if (task == current)
|
|
update_debugctlmsr(debugctl);
|
|
local_irq_enable();
|
|
}
|
|
|
|
/*
|
|
* Enable single or block step.
|
|
*/
|
|
static void enable_step(struct task_struct *child, bool block)
|
|
{
|
|
/*
|
|
* Make sure block stepping (BTF) is not enabled unless it should be.
|
|
* Note that we don't try to worry about any is_setting_trap_flag()
|
|
* instructions after the first when using block stepping.
|
|
* So no one should try to use debugger block stepping in a program
|
|
* that uses user-mode single stepping itself.
|
|
*/
|
|
if (enable_single_step(child) && block)
|
|
set_task_blockstep(child, true);
|
|
else if (test_tsk_thread_flag(child, TIF_BLOCKSTEP))
|
|
set_task_blockstep(child, false);
|
|
}
|
|
|
|
void user_enable_single_step(struct task_struct *child)
|
|
{
|
|
enable_step(child, 0);
|
|
}
|
|
|
|
void user_enable_block_step(struct task_struct *child)
|
|
{
|
|
enable_step(child, 1);
|
|
}
|
|
|
|
void user_disable_single_step(struct task_struct *child)
|
|
{
|
|
/*
|
|
* Make sure block stepping (BTF) is disabled.
|
|
*/
|
|
if (test_tsk_thread_flag(child, TIF_BLOCKSTEP))
|
|
set_task_blockstep(child, false);
|
|
|
|
/* Always clear TIF_SINGLESTEP... */
|
|
clear_tsk_thread_flag(child, TIF_SINGLESTEP);
|
|
|
|
/* But touch TF only if it was set by us.. */
|
|
if (test_and_clear_tsk_thread_flag(child, TIF_FORCED_TF))
|
|
task_pt_regs(child)->flags &= ~X86_EFLAGS_TF;
|
|
}
|