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/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 1992 Ross Biro
* Copyright (C) Linus Torvalds
* Copyright (C) 1994, 95, 96, 97, 98, 2000 Ralf Baechle
* Copyright (C) 1996 David S. Miller
* Kevin D. Kissell, kevink@mips.com and Carsten Langgaard, carstenl@mips.com
* Copyright (C) 1999 MIPS Technologies, Inc.
* Copyright (C) 2000 Ulf Carlsson
*
* At this time Linux/MIPS64 only supports syscall tracing, even for 32-bit
* binaries.
*/
#include <linux/compiler.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/errno.h>
#include <linux/ptrace.h>
#include <linux/smp.h>
#include <linux/user.h>
#include <linux/security.h>
#include <linux/audit.h>
#include <linux/seccomp.h>
#include <asm/byteorder.h>
#include <asm/cpu.h>
#include <asm/rlxregs.h>
#include <asm/pgtable.h>
#include <asm/page.h>
#include <asm/system.h>
#include <asm/uaccess.h>
#include <asm/bootinfo.h>
#include <asm/reg.h>
/*
* Called by kernel/ptrace.c when detaching..
*
* Make sure single step bits etc are not set.
*/
void ptrace_disable(struct task_struct *child)
{
/* Don't load the watchpoint registers for the ex-child. */
//clear_tsk_thread_flag(child, TIF_LOAD_WATCH);
}
/*
* Read a general register set. We always use the 64-bit format, even
* for 32-bit kernels and for 32-bit processes on a 64-bit kernel.
* Registers are sign extended to fill the available space.
*/
int ptrace_getregs(struct task_struct *child, __s64 __user *data)
{
struct pt_regs *regs;
int i;
if (!access_ok(VERIFY_WRITE, data, 38 * 8))
return -EIO;
regs = task_pt_regs(child);
for (i = 0; i < 32; i++)
__put_user((long)regs->regs[i], data + i);
__put_user((long)regs->lo, data + EF_LO - EF_R0);
__put_user((long)regs->hi, data + EF_HI - EF_R0);
__put_user((long)regs->cp0_epc, data + EF_CP0_EPC - EF_R0);
__put_user((long)regs->cp0_badvaddr, data + EF_CP0_BADVADDR - EF_R0);
__put_user((long)regs->cp0_status, data + EF_CP0_STATUS - EF_R0);
__put_user((long)regs->cp0_cause, data + EF_CP0_CAUSE - EF_R0);
return 0;
}
/*
* Write a general register set. As for PTRACE_GETREGS, we always use
* the 64-bit format. On a 32-bit kernel only the lower order half
* (according to endianness) will be used.
*/
int ptrace_setregs(struct task_struct *child, __s64 __user *data)
{
struct pt_regs *regs;
int i;
if (!access_ok(VERIFY_READ, data, 38 * 8))
return -EIO;
regs = task_pt_regs(child);
for (i = 0; i < 32; i++)
__get_user(regs->regs[i], data + i);
__get_user(regs->lo, data + EF_LO - EF_R0);
__get_user(regs->hi, data + EF_HI - EF_R0);
__get_user(regs->cp0_epc, data + EF_CP0_EPC - EF_R0);
/* badvaddr, status, and cause may not be written. */
return 0;
}
long arch_ptrace(struct task_struct *child, long request, long addr, long data)
{
int ret;
switch (request) {
/* when I and D space are separate, these will need to be fixed. */
case PTRACE_PEEKTEXT: /* read word at location addr. */
case PTRACE_PEEKDATA:
ret = generic_ptrace_peekdata(child, addr, data);
break;
/* Read the word at location addr in the USER area. */
case PTRACE_PEEKUSR: {
struct pt_regs *regs;
unsigned long tmp = 0;
regs = task_pt_regs(child);
ret = 0; /* Default return value. */
switch (addr) {
case 0 ... 31:
tmp = regs->regs[addr];
break;
case PC:
tmp = regs->cp0_epc;
break;
case CAUSE:
tmp = regs->cp0_cause;
break;
case BADVADDR:
tmp = regs->cp0_badvaddr;
break;
case MMHI:
tmp = regs->hi;
break;
case MMLO:
tmp = regs->lo;
break;
default:
tmp = 0;
ret = -EIO;
goto out;
}
ret = put_user(tmp, (unsigned long __user *) data);
break;
}
/* when I and D space are separate, this will have to be fixed. */
case PTRACE_POKETEXT: /* write the word at location addr. */
case PTRACE_POKEDATA:
ret = generic_ptrace_pokedata(child, addr, data);
break;
case PTRACE_POKEUSR: {
struct pt_regs *regs;
ret = 0;
regs = task_pt_regs(child);
switch (addr) {
case 0 ... 31:
regs->regs[addr] = data;
break;
case PC:
regs->cp0_epc = data;
break;
case MMHI:
regs->hi = data;
break;
case MMLO:
regs->lo = data;
break;
default:
/* The rest are not allowed. */
ret = -EIO;
break;
}
break;
}
case PTRACE_GETREGS:
ret = ptrace_getregs(child, (__s64 __user *) data);
break;
case PTRACE_SETREGS:
ret = ptrace_setregs(child, (__s64 __user *) data);
break;
case PTRACE_SYSCALL: /* continue and stop at next (return from) syscall */
case PTRACE_CONT: { /* restart after signal. */
ret = -EIO;
if (!valid_signal(data))
break;
if (request == PTRACE_SYSCALL) {
set_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
}
else {
clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
}
child->exit_code = data;
wake_up_process(child);
ret = 0;
break;
}
/*
* make the child exit. Best I can do is send it a sigkill.
* perhaps it should be put in the status that it wants to
* exit.
*/
case PTRACE_KILL:
ret = 0;
if (child->exit_state == EXIT_ZOMBIE) /* already dead */
break;
child->exit_code = SIGKILL;
wake_up_process(child);
break;
case PTRACE_GET_THREAD_AREA:
ret = put_user(task_thread_info(child)->tp_value,
(unsigned long __user *) data);
break;
default:
ret = ptrace_request(child, request, addr, data);
break;
}
out:
return ret;
}
static inline int audit_arch(void)
{
int arch = EM_MIPS;
#ifdef CONFIG_CPU_LITTLE_ENDIAN
arch |= __AUDIT_ARCH_LE;
#endif
return arch;
}
/*
* Notification of system call entry/exit
* - triggered by current->work.syscall_trace
*/
asmlinkage void do_syscall_trace(struct pt_regs *regs, int entryexit)
{
/* do the secure computing check first */
if (!entryexit)
secure_computing(regs->regs[0]);
if (unlikely(current->audit_context) && entryexit)
audit_syscall_exit(AUDITSC_RESULT(regs->regs[2]),
regs->regs[2]);
if (!(current->ptrace & PT_PTRACED))
goto out;
if (!test_thread_flag(TIF_SYSCALL_TRACE))
goto out;
/* The 0x80 provides a way for the tracing parent to distinguish
between a syscall stop and SIGTRAP delivery */
ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD) ?
0x80 : 0));
/*
* this isn't the same as continuing with a signal, but it will do
* for normal use. strace only continues with a signal if the
* stopping signal is not SIGTRAP. -brl
*/
if (current->exit_code) {
send_sig(current->exit_code, current, 1);
current->exit_code = 0;
}
out:
if (unlikely(current->audit_context) && !entryexit)
audit_syscall_entry(audit_arch(), regs->regs[0],
regs->regs[4], regs->regs[5],
regs->regs[6], regs->regs[7]);
}
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