mirror of
https://github.com/torvalds/linux
synced 2024-11-05 18:23:50 +00:00
35bca36cf7
ptrace_traceme() consolidation made ret = ptrace_traceme(); dead write. Signed-off-by: Alexey Dobriyan <adobriyan@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
601 lines
14 KiB
C
601 lines
14 KiB
C
/* ptrace.c: Sparc process tracing support.
|
|
*
|
|
* Copyright (C) 1996 David S. Miller (davem@caipfs.rutgers.edu)
|
|
*
|
|
* Based upon code written by Ross Biro, Linus Torvalds, Bob Manson,
|
|
* and David Mosberger.
|
|
*
|
|
* Added Linux support -miguel (weird, eh?, the orignal code was meant
|
|
* to emulate SunOS).
|
|
*/
|
|
|
|
#include <linux/kernel.h>
|
|
#include <linux/sched.h>
|
|
#include <linux/mm.h>
|
|
#include <linux/errno.h>
|
|
#include <linux/ptrace.h>
|
|
#include <linux/user.h>
|
|
#include <linux/smp.h>
|
|
#include <linux/smp_lock.h>
|
|
#include <linux/security.h>
|
|
#include <linux/signal.h>
|
|
|
|
#include <asm/pgtable.h>
|
|
#include <asm/system.h>
|
|
#include <asm/uaccess.h>
|
|
|
|
#define MAGIC_CONSTANT 0x80000000
|
|
|
|
|
|
/* Returning from ptrace is a bit tricky because the syscall return
|
|
* low level code assumes any value returned which is negative and
|
|
* is a valid errno will mean setting the condition codes to indicate
|
|
* an error return. This doesn't work, so we have this hook.
|
|
*/
|
|
static inline void pt_error_return(struct pt_regs *regs, unsigned long error)
|
|
{
|
|
regs->u_regs[UREG_I0] = error;
|
|
regs->psr |= PSR_C;
|
|
regs->pc = regs->npc;
|
|
regs->npc += 4;
|
|
}
|
|
|
|
static inline void pt_succ_return(struct pt_regs *regs, unsigned long value)
|
|
{
|
|
regs->u_regs[UREG_I0] = value;
|
|
regs->psr &= ~PSR_C;
|
|
regs->pc = regs->npc;
|
|
regs->npc += 4;
|
|
}
|
|
|
|
static void
|
|
pt_succ_return_linux(struct pt_regs *regs, unsigned long value, long __user *addr)
|
|
{
|
|
if (put_user(value, addr)) {
|
|
pt_error_return(regs, EFAULT);
|
|
return;
|
|
}
|
|
regs->u_regs[UREG_I0] = 0;
|
|
regs->psr &= ~PSR_C;
|
|
regs->pc = regs->npc;
|
|
regs->npc += 4;
|
|
}
|
|
|
|
static void
|
|
pt_os_succ_return (struct pt_regs *regs, unsigned long val, long __user *addr)
|
|
{
|
|
if (current->personality == PER_SUNOS)
|
|
pt_succ_return (regs, val);
|
|
else
|
|
pt_succ_return_linux (regs, val, addr);
|
|
}
|
|
|
|
/* Fuck me gently with a chainsaw... */
|
|
static inline void read_sunos_user(struct pt_regs *regs, unsigned long offset,
|
|
struct task_struct *tsk, long __user *addr)
|
|
{
|
|
struct pt_regs *cregs = tsk->thread.kregs;
|
|
struct thread_info *t = task_thread_info(tsk);
|
|
int v;
|
|
|
|
if(offset >= 1024)
|
|
offset -= 1024; /* whee... */
|
|
if(offset & ((sizeof(unsigned long) - 1))) {
|
|
pt_error_return(regs, EIO);
|
|
return;
|
|
}
|
|
if(offset >= 16 && offset < 784) {
|
|
offset -= 16; offset >>= 2;
|
|
pt_os_succ_return(regs, *(((unsigned long *)(&t->reg_window[0]))+offset), addr);
|
|
return;
|
|
}
|
|
if(offset >= 784 && offset < 832) {
|
|
offset -= 784; offset >>= 2;
|
|
pt_os_succ_return(regs, *(((unsigned long *)(&t->rwbuf_stkptrs[0]))+offset), addr);
|
|
return;
|
|
}
|
|
switch(offset) {
|
|
case 0:
|
|
v = t->ksp;
|
|
break;
|
|
case 4:
|
|
v = t->kpc;
|
|
break;
|
|
case 8:
|
|
v = t->kpsr;
|
|
break;
|
|
case 12:
|
|
v = t->uwinmask;
|
|
break;
|
|
case 832:
|
|
v = t->w_saved;
|
|
break;
|
|
case 896:
|
|
v = cregs->u_regs[UREG_I0];
|
|
break;
|
|
case 900:
|
|
v = cregs->u_regs[UREG_I1];
|
|
break;
|
|
case 904:
|
|
v = cregs->u_regs[UREG_I2];
|
|
break;
|
|
case 908:
|
|
v = cregs->u_regs[UREG_I3];
|
|
break;
|
|
case 912:
|
|
v = cregs->u_regs[UREG_I4];
|
|
break;
|
|
case 916:
|
|
v = cregs->u_regs[UREG_I5];
|
|
break;
|
|
case 920:
|
|
v = cregs->u_regs[UREG_I6];
|
|
break;
|
|
case 924:
|
|
if(tsk->thread.flags & MAGIC_CONSTANT)
|
|
v = cregs->u_regs[UREG_G1];
|
|
else
|
|
v = 0;
|
|
break;
|
|
case 940:
|
|
v = cregs->u_regs[UREG_I0];
|
|
break;
|
|
case 944:
|
|
v = cregs->u_regs[UREG_I1];
|
|
break;
|
|
|
|
case 948:
|
|
/* Isn't binary compatibility _fun_??? */
|
|
if(cregs->psr & PSR_C)
|
|
v = cregs->u_regs[UREG_I0] << 24;
|
|
else
|
|
v = 0;
|
|
break;
|
|
|
|
/* Rest of them are completely unsupported. */
|
|
default:
|
|
printk("%s [%d]: Wants to read user offset %ld\n",
|
|
current->comm, current->pid, offset);
|
|
pt_error_return(regs, EIO);
|
|
return;
|
|
}
|
|
if (current->personality == PER_SUNOS)
|
|
pt_succ_return (regs, v);
|
|
else
|
|
pt_succ_return_linux (regs, v, addr);
|
|
return;
|
|
}
|
|
|
|
static inline void write_sunos_user(struct pt_regs *regs, unsigned long offset,
|
|
struct task_struct *tsk)
|
|
{
|
|
struct pt_regs *cregs = tsk->thread.kregs;
|
|
struct thread_info *t = task_thread_info(tsk);
|
|
unsigned long value = regs->u_regs[UREG_I3];
|
|
|
|
if(offset >= 1024)
|
|
offset -= 1024; /* whee... */
|
|
if(offset & ((sizeof(unsigned long) - 1)))
|
|
goto failure;
|
|
if(offset >= 16 && offset < 784) {
|
|
offset -= 16; offset >>= 2;
|
|
*(((unsigned long *)(&t->reg_window[0]))+offset) = value;
|
|
goto success;
|
|
}
|
|
if(offset >= 784 && offset < 832) {
|
|
offset -= 784; offset >>= 2;
|
|
*(((unsigned long *)(&t->rwbuf_stkptrs[0]))+offset) = value;
|
|
goto success;
|
|
}
|
|
switch(offset) {
|
|
case 896:
|
|
cregs->u_regs[UREG_I0] = value;
|
|
break;
|
|
case 900:
|
|
cregs->u_regs[UREG_I1] = value;
|
|
break;
|
|
case 904:
|
|
cregs->u_regs[UREG_I2] = value;
|
|
break;
|
|
case 908:
|
|
cregs->u_regs[UREG_I3] = value;
|
|
break;
|
|
case 912:
|
|
cregs->u_regs[UREG_I4] = value;
|
|
break;
|
|
case 916:
|
|
cregs->u_regs[UREG_I5] = value;
|
|
break;
|
|
case 920:
|
|
cregs->u_regs[UREG_I6] = value;
|
|
break;
|
|
case 924:
|
|
cregs->u_regs[UREG_I7] = value;
|
|
break;
|
|
case 940:
|
|
cregs->u_regs[UREG_I0] = value;
|
|
break;
|
|
case 944:
|
|
cregs->u_regs[UREG_I1] = value;
|
|
break;
|
|
|
|
/* Rest of them are completely unsupported or "no-touch". */
|
|
default:
|
|
printk("%s [%d]: Wants to write user offset %ld\n",
|
|
current->comm, current->pid, offset);
|
|
goto failure;
|
|
}
|
|
success:
|
|
pt_succ_return(regs, 0);
|
|
return;
|
|
failure:
|
|
pt_error_return(regs, EIO);
|
|
return;
|
|
}
|
|
|
|
/* #define ALLOW_INIT_TRACING */
|
|
/* #define DEBUG_PTRACE */
|
|
|
|
#ifdef DEBUG_PTRACE
|
|
char *pt_rq [] = {
|
|
/* 0 */ "TRACEME", "PEEKTEXT", "PEEKDATA", "PEEKUSR",
|
|
/* 4 */ "POKETEXT", "POKEDATA", "POKEUSR", "CONT",
|
|
/* 8 */ "KILL", "SINGLESTEP", "SUNATTACH", "SUNDETACH",
|
|
/* 12 */ "GETREGS", "SETREGS", "GETFPREGS", "SETFPREGS",
|
|
/* 16 */ "READDATA", "WRITEDATA", "READTEXT", "WRITETEXT",
|
|
/* 20 */ "GETFPAREGS", "SETFPAREGS", "unknown", "unknown",
|
|
/* 24 */ "SYSCALL", ""
|
|
};
|
|
#endif
|
|
|
|
/*
|
|
* Called by kernel/ptrace.c when detaching..
|
|
*
|
|
* Make sure single step bits etc are not set.
|
|
*/
|
|
void ptrace_disable(struct task_struct *child)
|
|
{
|
|
/* nothing to do */
|
|
}
|
|
|
|
asmlinkage void do_ptrace(struct pt_regs *regs)
|
|
{
|
|
unsigned long request = regs->u_regs[UREG_I0];
|
|
unsigned long pid = regs->u_regs[UREG_I1];
|
|
unsigned long addr = regs->u_regs[UREG_I2];
|
|
unsigned long data = regs->u_regs[UREG_I3];
|
|
unsigned long addr2 = regs->u_regs[UREG_I4];
|
|
struct task_struct *child;
|
|
int ret;
|
|
|
|
lock_kernel();
|
|
#ifdef DEBUG_PTRACE
|
|
{
|
|
char *s;
|
|
|
|
if ((request >= 0) && (request <= 24))
|
|
s = pt_rq [request];
|
|
else
|
|
s = "unknown";
|
|
|
|
if (request == PTRACE_POKEDATA && data == 0x91d02001){
|
|
printk ("do_ptrace: breakpoint pid=%d, addr=%08lx addr2=%08lx\n",
|
|
pid, addr, addr2);
|
|
} else
|
|
printk("do_ptrace: rq=%s(%d) pid=%d addr=%08lx data=%08lx addr2=%08lx\n",
|
|
s, (int) request, (int) pid, addr, data, addr2);
|
|
}
|
|
#endif
|
|
|
|
if (request == PTRACE_TRACEME) {
|
|
ret = ptrace_traceme();
|
|
if (ret < 0)
|
|
pt_error_return(regs, -ret);
|
|
else
|
|
pt_succ_return(regs, 0);
|
|
goto out;
|
|
}
|
|
|
|
child = ptrace_get_task_struct(pid);
|
|
if (IS_ERR(child)) {
|
|
ret = PTR_ERR(child);
|
|
pt_error_return(regs, -ret);
|
|
goto out;
|
|
}
|
|
|
|
if ((current->personality == PER_SUNOS && request == PTRACE_SUNATTACH)
|
|
|| (current->personality != PER_SUNOS && request == PTRACE_ATTACH)) {
|
|
if (ptrace_attach(child)) {
|
|
pt_error_return(regs, EPERM);
|
|
goto out_tsk;
|
|
}
|
|
pt_succ_return(regs, 0);
|
|
goto out_tsk;
|
|
}
|
|
|
|
ret = ptrace_check_attach(child, request == PTRACE_KILL);
|
|
if (ret < 0) {
|
|
pt_error_return(regs, -ret);
|
|
goto out_tsk;
|
|
}
|
|
|
|
switch(request) {
|
|
case PTRACE_PEEKTEXT: /* read word at location addr. */
|
|
case PTRACE_PEEKDATA: {
|
|
unsigned long tmp;
|
|
|
|
if (access_process_vm(child, addr,
|
|
&tmp, sizeof(tmp), 0) == sizeof(tmp))
|
|
pt_os_succ_return(regs, tmp, (long __user *)data);
|
|
else
|
|
pt_error_return(regs, EIO);
|
|
goto out_tsk;
|
|
}
|
|
|
|
case PTRACE_PEEKUSR:
|
|
read_sunos_user(regs, addr, child, (long __user *) data);
|
|
goto out_tsk;
|
|
|
|
case PTRACE_POKEUSR:
|
|
write_sunos_user(regs, addr, child);
|
|
goto out_tsk;
|
|
|
|
case PTRACE_POKETEXT: /* write the word at location addr. */
|
|
case PTRACE_POKEDATA: {
|
|
if (access_process_vm(child, addr,
|
|
&data, sizeof(data), 1) == sizeof(data))
|
|
pt_succ_return(regs, 0);
|
|
else
|
|
pt_error_return(regs, EIO);
|
|
goto out_tsk;
|
|
}
|
|
|
|
case PTRACE_GETREGS: {
|
|
struct pt_regs __user *pregs = (struct pt_regs __user *) addr;
|
|
struct pt_regs *cregs = child->thread.kregs;
|
|
int rval;
|
|
|
|
if (!access_ok(VERIFY_WRITE, pregs, sizeof(struct pt_regs))) {
|
|
rval = -EFAULT;
|
|
pt_error_return(regs, -rval);
|
|
goto out_tsk;
|
|
}
|
|
__put_user(cregs->psr, (&pregs->psr));
|
|
__put_user(cregs->pc, (&pregs->pc));
|
|
__put_user(cregs->npc, (&pregs->npc));
|
|
__put_user(cregs->y, (&pregs->y));
|
|
for(rval = 1; rval < 16; rval++)
|
|
__put_user(cregs->u_regs[rval], (&pregs->u_regs[rval - 1]));
|
|
pt_succ_return(regs, 0);
|
|
#ifdef DEBUG_PTRACE
|
|
printk ("PC=%x nPC=%x o7=%x\n", cregs->pc, cregs->npc, cregs->u_regs [15]);
|
|
#endif
|
|
goto out_tsk;
|
|
}
|
|
|
|
case PTRACE_SETREGS: {
|
|
struct pt_regs __user *pregs = (struct pt_regs __user *) addr;
|
|
struct pt_regs *cregs = child->thread.kregs;
|
|
unsigned long psr, pc, npc, y;
|
|
int i;
|
|
|
|
/* Must be careful, tracing process can only set certain
|
|
* bits in the psr.
|
|
*/
|
|
if (!access_ok(VERIFY_READ, pregs, sizeof(struct pt_regs))) {
|
|
pt_error_return(regs, EFAULT);
|
|
goto out_tsk;
|
|
}
|
|
__get_user(psr, (&pregs->psr));
|
|
__get_user(pc, (&pregs->pc));
|
|
__get_user(npc, (&pregs->npc));
|
|
__get_user(y, (&pregs->y));
|
|
psr &= PSR_ICC;
|
|
cregs->psr &= ~PSR_ICC;
|
|
cregs->psr |= psr;
|
|
if (!((pc | npc) & 3)) {
|
|
cregs->pc = pc;
|
|
cregs->npc =npc;
|
|
}
|
|
cregs->y = y;
|
|
for(i = 1; i < 16; i++)
|
|
__get_user(cregs->u_regs[i], (&pregs->u_regs[i-1]));
|
|
pt_succ_return(regs, 0);
|
|
goto out_tsk;
|
|
}
|
|
|
|
case PTRACE_GETFPREGS: {
|
|
struct fps {
|
|
unsigned long regs[32];
|
|
unsigned long fsr;
|
|
unsigned long flags;
|
|
unsigned long extra;
|
|
unsigned long fpqd;
|
|
struct fq {
|
|
unsigned long *insnaddr;
|
|
unsigned long insn;
|
|
} fpq[16];
|
|
};
|
|
struct fps __user *fps = (struct fps __user *) addr;
|
|
int i;
|
|
|
|
if (!access_ok(VERIFY_WRITE, fps, sizeof(struct fps))) {
|
|
i = -EFAULT;
|
|
pt_error_return(regs, -i);
|
|
goto out_tsk;
|
|
}
|
|
for(i = 0; i < 32; i++)
|
|
__put_user(child->thread.float_regs[i], (&fps->regs[i]));
|
|
__put_user(child->thread.fsr, (&fps->fsr));
|
|
__put_user(child->thread.fpqdepth, (&fps->fpqd));
|
|
__put_user(0, (&fps->flags));
|
|
__put_user(0, (&fps->extra));
|
|
for(i = 0; i < 16; i++) {
|
|
__put_user(child->thread.fpqueue[i].insn_addr,
|
|
(&fps->fpq[i].insnaddr));
|
|
__put_user(child->thread.fpqueue[i].insn, (&fps->fpq[i].insn));
|
|
}
|
|
pt_succ_return(regs, 0);
|
|
goto out_tsk;
|
|
}
|
|
|
|
case PTRACE_SETFPREGS: {
|
|
struct fps {
|
|
unsigned long regs[32];
|
|
unsigned long fsr;
|
|
unsigned long flags;
|
|
unsigned long extra;
|
|
unsigned long fpqd;
|
|
struct fq {
|
|
unsigned long *insnaddr;
|
|
unsigned long insn;
|
|
} fpq[16];
|
|
};
|
|
struct fps __user *fps = (struct fps __user *) addr;
|
|
int i;
|
|
|
|
if (!access_ok(VERIFY_READ, fps, sizeof(struct fps))) {
|
|
i = -EFAULT;
|
|
pt_error_return(regs, -i);
|
|
goto out_tsk;
|
|
}
|
|
copy_from_user(&child->thread.float_regs[0], &fps->regs[0], (32 * sizeof(unsigned long)));
|
|
__get_user(child->thread.fsr, (&fps->fsr));
|
|
__get_user(child->thread.fpqdepth, (&fps->fpqd));
|
|
for(i = 0; i < 16; i++) {
|
|
__get_user(child->thread.fpqueue[i].insn_addr,
|
|
(&fps->fpq[i].insnaddr));
|
|
__get_user(child->thread.fpqueue[i].insn, (&fps->fpq[i].insn));
|
|
}
|
|
pt_succ_return(regs, 0);
|
|
goto out_tsk;
|
|
}
|
|
|
|
case PTRACE_READTEXT:
|
|
case PTRACE_READDATA: {
|
|
int res = ptrace_readdata(child, addr,
|
|
(void __user *) addr2, data);
|
|
|
|
if (res == data) {
|
|
pt_succ_return(regs, 0);
|
|
goto out_tsk;
|
|
}
|
|
/* Partial read is an IO failure */
|
|
if (res >= 0)
|
|
res = -EIO;
|
|
pt_error_return(regs, -res);
|
|
goto out_tsk;
|
|
}
|
|
|
|
case PTRACE_WRITETEXT:
|
|
case PTRACE_WRITEDATA: {
|
|
int res = ptrace_writedata(child, (void __user *) addr2,
|
|
addr, data);
|
|
|
|
if (res == data) {
|
|
pt_succ_return(regs, 0);
|
|
goto out_tsk;
|
|
}
|
|
/* Partial write is an IO failure */
|
|
if (res >= 0)
|
|
res = -EIO;
|
|
pt_error_return(regs, -res);
|
|
goto out_tsk;
|
|
}
|
|
|
|
case PTRACE_SYSCALL: /* continue and stop at (return from) syscall */
|
|
addr = 1;
|
|
|
|
case PTRACE_CONT: { /* restart after signal. */
|
|
if (!valid_signal(data)) {
|
|
pt_error_return(regs, EIO);
|
|
goto out_tsk;
|
|
}
|
|
|
|
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;
|
|
#ifdef DEBUG_PTRACE
|
|
printk("CONT: %s [%d]: set exit_code = %x %lx %lx\n",
|
|
child->comm, child->pid, child->exit_code,
|
|
child->thread.kregs->pc,
|
|
child->thread.kregs->npc);
|
|
#endif
|
|
wake_up_process(child);
|
|
pt_succ_return(regs, 0);
|
|
goto out_tsk;
|
|
}
|
|
|
|
/*
|
|
* 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: {
|
|
if (child->exit_state == EXIT_ZOMBIE) { /* already dead */
|
|
pt_succ_return(regs, 0);
|
|
goto out_tsk;
|
|
}
|
|
wake_up_process(child);
|
|
child->exit_code = SIGKILL;
|
|
pt_succ_return(regs, 0);
|
|
goto out_tsk;
|
|
}
|
|
|
|
case PTRACE_SUNDETACH: { /* detach a process that was attached. */
|
|
int err = ptrace_detach(child, data);
|
|
if (err) {
|
|
pt_error_return(regs, EIO);
|
|
goto out_tsk;
|
|
}
|
|
pt_succ_return(regs, 0);
|
|
goto out_tsk;
|
|
}
|
|
|
|
/* PTRACE_DUMPCORE unsupported... */
|
|
|
|
default: {
|
|
int err = ptrace_request(child, request, addr, data);
|
|
if (err)
|
|
pt_error_return(regs, -err);
|
|
else
|
|
pt_succ_return(regs, 0);
|
|
goto out_tsk;
|
|
}
|
|
}
|
|
out_tsk:
|
|
if (child)
|
|
put_task_struct(child);
|
|
out:
|
|
unlock_kernel();
|
|
}
|
|
|
|
asmlinkage void syscall_trace(void)
|
|
{
|
|
#ifdef DEBUG_PTRACE
|
|
printk("%s [%d]: syscall_trace\n", current->comm, current->pid);
|
|
#endif
|
|
if (!test_thread_flag(TIF_SYSCALL_TRACE))
|
|
return;
|
|
if (!(current->ptrace & PT_PTRACED))
|
|
return;
|
|
current->thread.flags ^= MAGIC_CONSTANT;
|
|
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
|
|
*/
|
|
#ifdef DEBUG_PTRACE
|
|
printk("%s [%d]: syscall_trace exit= %x\n", current->comm,
|
|
current->pid, current->exit_code);
|
|
#endif
|
|
if (current->exit_code) {
|
|
send_sig (current->exit_code, current, 1);
|
|
current->exit_code = 0;
|
|
}
|
|
}
|