/*
* ptrace for 32-bit processes running on a 64-bit kernel.
*
* PowerPC version
* Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
*
* Derived from "arch/m68k/kernel/ptrace.c"
* Copyright (C) 1994 by Hamish Macdonald
* Taken from linux/kernel/ptrace.c and modified for M680x0.
* linux/kernel/ptrace.c is by Ross Biro 1/23/92, edited by Linus Torvalds
*
* Modified by Cort Dougan (cort@hq.fsmlabs.com)
* and Paul Mackerras (paulus@samba.org).
*
* 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.
*/
#include <linux/config.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/smp.h>
#include <linux/smp_lock.h>
#include <linux/errno.h>
#include <linux/ptrace.h>
#include <linux/user.h>
#include <linux/security.h>
#include <linux/signal.h>
#include <asm/uaccess.h>
#include <asm/page.h>
#include <asm/pgtable.h>
#include <asm/system.h>
#include <asm/ptrace-common.h>
/*
* does not yet catch signals sent when the child dies.
* in exit.c or in signal.c.
*/
long compat_sys_ptrace(int request, int pid, unsigned long addr,
unsigned long data)
{
struct task_struct *child;
int ret = -EPERM;
lock_kernel();
if (request == PTRACE_TRACEME) {
/* are we already being traced? */
if (current->ptrace & PT_PTRACED)
goto out;
ret = security_ptrace(current->parent, current);
if (ret)
goto out;
/* set the ptrace bit in the process flags. */
current->ptrace |= PT_PTRACED;
ret = 0;
goto out;
}
ret = -ESRCH;
read_lock(&tasklist_lock);
child = find_task_by_pid(pid);
if (child)
get_task_struct(child);
read_unlock(&tasklist_lock);
if (!child)
goto out;
ret = -EPERM;
if (pid == 1) /* you may not mess with init */
goto out_tsk;
if (request == PTRACE_ATTACH) {
ret = ptrace_attach(child);
goto out_tsk;
}
ret = ptrace_check_attach(child, request == PTRACE_KILL);
if (ret < 0)
goto out_tsk;
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: {
unsigned int tmp;
int copied;
copied = access_process_vm(child, addr, &tmp, sizeof(tmp), 0);
ret = -EIO;
if (copied != sizeof(tmp))
break;
ret = put_user(tmp, (u32 __user *)data);
break;
}
/*
* Read 4 bytes of the other process' storage
* data is a pointer specifying where the user wants the
* 4 bytes copied into
* addr is a pointer in the user's storage that contains an 8 byte
* address in the other process of the 4 bytes that is to be read
* (this is run in a 32-bit process looking at a 64-bit process)
* when I and D space are separate, these will need to be fixed.
*/
case PPC_PTRACE_PEEKTEXT_3264:
case PPC_PTRACE_PEEKDATA_3264: {
u32 tmp;
int copied;
u32 __user * addrOthers;
ret = -EIO;
/* Get the addr in the other process that we want to read */
if (get_user(addrOthers, (u32 __user * __user *)addr) != 0)
break;
copied = access_process_vm(child, (u64)addrOthers, &tmp,
sizeof(tmp), 0);
if (copied != sizeof(tmp))
break;
ret = put_user(tmp, (u32 __user *)data);
break;
}
/* Read a register (specified by ADDR) out of the "user area" */
case PTRACE_PEEKUSR: {
int index;
unsigned long tmp;
ret = -EIO;
/* convert to index and check */
index = (unsigned long) addr >> 2;
if ((addr & 3) || (index > PT_FPSCR32))
break;
if (index < PT_FPR0) {
tmp = get_reg(child, index);
} else {
flush_fp_to_thread(child);
/*
* the user space code considers the floating point
* to be an array of unsigned int (32 bits) - the
* index passed in is based on this assumption.
*/
tmp = ((unsigned int *)child->thread.fpr)[index - PT_FPR0];
}
ret = put_user((unsigned int)tmp, (u32 __user *)data);
break;
}
/*
* Read 4 bytes out of the other process' pt_regs area
* data is a pointer specifying where the user wants the
* 4 bytes copied into
* addr is the offset into the other process' pt_regs structure
* that is to be read
* (this is run in a 32-bit process looking at a 64-bit process)
*/
case PPC_PTRACE_PEEKUSR_3264: {
u32 index;
u32 reg32bits;
u64 tmp;
u32 numReg;
u32 part;
ret = -EIO;
/* Determine which register the user wants */
index = (u64)addr >> 2;
numReg = index / 2;
/* Determine which part of the register the user wants */
if (index % 2)
part = 1; /* want the 2nd half of the register (right-most). */
else
part = 0; /* want the 1st half of the register (left-most). */
/* Validate the input - check to see if address is on the wrong boundary or beyond the end of the user area */
if ((addr & 3) || numReg > PT_FPSCR)
break;
if (numReg >= PT_FPR0) {
flush_fp_to_thread(child);
tmp = ((unsigned long int *)child->thread.fpr)[numReg - PT_FPR0];
} else { /* register within PT_REGS struct */
tmp = get_reg(child, numReg);
}
reg32bits = ((u32*)&tmp)[part];
ret = put_user(reg32bits, (u32 __user *)data);
break;
}
/* If I and D space are separate, this will have to be fixed. */
case PTRACE_POKETEXT: /* write the word at location addr. */
case PTRACE_POKEDATA: {
unsigned int tmp;
tmp = data;
ret = 0;
if (access_process_vm(child, addr, &tmp, sizeof(tmp), 1)
== sizeof(tmp))
break;
ret = -EIO;
break;
}
/*
* Write 4 bytes into the other process' storage
* data is the 4 bytes that the user wants written
* addr is a pointer in the user's storage that contains an
* 8 byte address in the other process where the 4 bytes
* that is to be written
* (this is run in a 32-bit process looking at a 64-bit process)
* when I and D space are separate, these will need to be fixed.
*/
case PPC_PTRACE_POKETEXT_3264:
case PPC_PTRACE_POKEDATA_3264: {
u32 tmp = data;
u32 __user * addrOthers;
/* Get the addr in the other process that we want to write into */
ret = -EIO;
if (get_user(addrOthers, (u32 __user * __user *)addr) != 0)
break;
ret = 0;
if (access_process_vm(child, (u64)addrOthers, &tmp,
sizeof(tmp), 1) == sizeof(tmp))
break;
ret = -EIO;
break;
}
/* write the word at location addr in the USER area */
case PTRACE_POKEUSR: {
unsigned long index;
ret = -EIO;
/* convert to index and check */
index = (unsigned long) addr >> 2;
if ((addr & 3) || (index > PT_FPSCR32))
break;
if (index == PT_ORIG_R3)
break;
if (index < PT_FPR0) {
ret = put_reg(child, index, data);
} else {
flush_fp_to_thread(child);
/*
* the user space code considers the floating point
* to be an array of unsigned int (32 bits) - the
* index passed in is based on this assumption.
*/
((unsigned int *)child->thread.fpr)[index - PT_FPR0] = data;
ret = 0;
}
break;
}
/*
* Write 4 bytes into the other process' pt_regs area
* data is the 4 bytes that the user wants written
* addr is the offset into the other process' pt_regs structure
* that is to be written into
* (this is run in a 32-bit process looking at a 64-bit process)
*/
case PPC_PTRACE_POKEUSR_3264: {
u32 index;
u32 numReg;
ret = -EIO;
/* Determine which register the user wants */
index = (u64)addr >> 2;
numReg = index / 2;
/*
* Validate the input - check to see if address is on the
* wrong boundary or beyond the end of the user area
*/
if ((addr & 3) || (numReg > PT_FPSCR))
break;
/* Insure it is a register we let them change */
if ((numReg == PT_ORIG_R3)
|| ((numReg > PT_CCR) && (numReg < PT_FPR0)))
break;
if (numReg >= PT_FPR0) {
flush_fp_to_thread(child);
}
if (numReg == PT_MSR)
data = (data & MSR_DEBUGCHANGE)
| (child->thread.regs->msr & ~MSR_DEBUGCHANGE);
((u32*)child->thread.regs)[index] = data;
ret = 0;
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;
/* make sure the single step bit is not set. */
clear_single_step(child);
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;
/* make sure the single step bit is not set. */
clear_single_step(child);
wake_up_process(child);
break;
}
case PTRACE_SINGLESTEP: { /* set the trap flag. */
ret = -EIO;
if (!valid_signal(data))
break;
clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
set_single_step(child);
child->exit_code = data;
/* give it a chance to run. */
wake_up_process(child);
ret = 0;
break;
}
case PTRACE_GET_DEBUGREG: {
ret = -EINVAL;
/* We only support one DABR and no IABRS at the moment */
if (addr > 0)
break;
ret = put_user(child->thread.dabr, (u32 __user *)data);
break;
}
case PTRACE_SET_DEBUGREG:
ret = ptrace_set_debugreg(child, addr, data);
break;
case PTRACE_DETACH:
ret = ptrace_detach(child, data);
break;
case PPC_PTRACE_GETREGS: { /* Get GPRs 0 - 31. */
int i;
unsigned long *reg = &((unsigned long *)child->thread.regs)[0];
unsigned int __user *tmp = (unsigned int __user *)addr;
for (i = 0; i < 32; i++) {
ret = put_user(*reg, tmp);
if (ret)
break;
reg++;
tmp++;
}
break;
}
case PPC_PTRACE_SETREGS: { /* Set GPRs 0 - 31. */
int i;
unsigned long *reg = &((unsigned long *)child->thread.regs)[0];
unsigned int __user *tmp = (unsigned int __user *)addr;
for (i = 0; i < 32; i++) {
ret = get_user(*reg, tmp);
if (ret)
break;
reg++;
tmp++;
}
break;
}
case PPC_PTRACE_GETFPREGS: { /* Get FPRs 0 - 31. */
int i;
unsigned long *reg = &((unsigned long *)child->thread.fpr)[0];
unsigned int __user *tmp = (unsigned int __user *)addr;
flush_fp_to_thread(child);
for (i = 0; i < 32; i++) {
ret = put_user(*reg, tmp);
if (ret)
break;
reg++;
tmp++;
}
break;
}
case PPC_PTRACE_SETFPREGS: { /* Get FPRs 0 - 31. */
int i;
unsigned long *reg = &((unsigned long *)child->thread.fpr)[0];
unsigned int __user *tmp = (unsigned int __user *)addr;
flush_fp_to_thread(child);
for (i = 0; i < 32; i++) {
ret = get_user(*reg, tmp);
if (ret)
break;
reg++;
tmp++;
}
break;
}
case PTRACE_GETEVENTMSG:
ret = put_user(child->ptrace_message, (unsigned int __user *) data);
break;
#ifdef CONFIG_ALTIVEC
case PTRACE_GETVRREGS:
/* Get the child altivec register state. */
flush_altivec_to_thread(child);
ret = get_vrregs((unsigned long __user *)data, child);
break;
case PTRACE_SETVRREGS:
/* Set the child altivec register state. */
flush_altivec_to_thread(child);
ret = set_vrregs(child, (unsigned long __user *)data);
break;
#endif
default:
ret = ptrace_request(child, request, addr, data);
break;
}
out_tsk:
put_task_struct(child);
out:
unlock_kernel();
return ret;
}
