/* ptrace.c: Sparc process tracing support.
*
* Copyright (C) 1996 David S. Miller (davem@caipfs.rutgers.edu)
* Copyright (C) 1997 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
*
* Based upon code written by Ross Biro, Linus Torvalds, Bob Manson,
* and David Mosberger.
*
* Added Linux support -miguel (weird, eh?, the original 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/asi.h>
#include <asm/pgtable.h>
#include <asm/system.h>
#include <asm/uaccess.h>
#include <asm/psrcompat.h>
#include <asm/visasm.h>
#include <asm/spitfire.h>
/* 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->tstate |= (TSTATE_ICARRY | TSTATE_XCARRY);
regs->tpc = regs->tnpc;
regs->tnpc += 4;
}
static inline void pt_succ_return(struct pt_regs *regs, unsigned long value)
{
regs->u_regs[UREG_I0] = value;
regs->tstate &= ~(TSTATE_ICARRY | TSTATE_XCARRY);
regs->tpc = regs->tnpc;
regs->tnpc += 4;
}
static inline void
pt_succ_return_linux(struct pt_regs *regs, unsigned long value, void __user *addr)
{
if (test_thread_flag(TIF_32BIT)) {
if (put_user(value, (unsigned int __user *) addr)) {
pt_error_return(regs, EFAULT);
return;
}
} else {
if (put_user(value, (long __user *) addr)) {
pt_error_return(regs, EFAULT);
return;
}
}
regs->u_regs[UREG_I0] = 0;
regs->tstate &= ~(TSTATE_ICARRY | TSTATE_XCARRY);
regs->tpc = regs->tnpc;
regs->tnpc += 4;
}
static void
pt_os_succ_return (struct pt_regs *regs, unsigned long val, void __user *addr)
{
if (current->personality == PER_SUNOS)
pt_succ_return (regs, val);
else
pt_succ_return_linux (regs, val, addr);
}
/* #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 */
}
/* To get the necessary page struct, access_process_vm() first calls
* get_user_pages(). This has done a flush_dcache_page() on the
* accessed page. Then our caller (copy_{to,from}_user_page()) did
* to memcpy to read/write the data from that page.
*
* Now, the only thing we have to do is:
* 1) flush the D-cache if it's possible than an illegal alias
* has been created
* 2) flush the I-cache if this is pre-cheetah and we did a write
*/
void flush_ptrace_access(struct vm_area_struct *vma, struct page *page,
unsigned long uaddr, void *kaddr,
unsigned long len, int write)
{
BUG_ON(len > PAGE_SIZE);
#ifdef DCACHE_ALIASING_POSSIBLE
/* If bit 13 of the kernel address we used to access the
* user page is the same as the virtual address that page
* is mapped to in the user's address space, we can skip the
* D-cache flush.
*/
if ((uaddr ^ kaddr) & (1UL << 13)) {
unsigned long start = __pa(kaddr);
unsigned long end = start + len;
if (tlb_type == spitfire) {
for (; start < end; start += 32)
spitfire_put_dcache_tag(va & 0x3fe0, 0x0);
} else {
for (; start < end; start += 32)
__asm__ __volatile__(
"stxa %%g0, [%0] %1\n\t"
"membar #Sync"
: /* no outputs */
: "r" (va),
"i" (ASI_DCACHE_INVALIDATE));
}
}
#endif
if (write && tlb_type == spitfire) {
unsigned long start = (unsigned long) kaddr;
unsigned long end = start + len;
for (; start < end; start += 32)
flushi(start);
}
}
asmlinkage void do_ptrace(struct pt_regs *regs)
{
int request = regs->u_regs[UREG_I0];
pid_t 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;
if (test_thread_flag(TIF_32BIT)) {
addr &= 0xffffffffUL;
data &= 0xffffffffUL;
addr2 &= 0xffffffffUL;
}
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=%016lx addr2=%016lx\n",
pid, addr, addr2);
} else
printk("do_ptrace: rq=%s(%d) pid=%d addr=%016lx data=%016lx addr2=%016lx\n",
s, request, pid, addr, data, addr2);
}
#endif
if (request == PTRACE_TRACEME) {
int ret;
/* are we already being traced? */
if (current->ptrace & PT_PTRACED) {
pt_error_return(regs, EPERM);
goto out;
}
ret = security_ptrace(current->parent, current);
if (ret) {
pt_error_return(regs, -ret);
goto out;
}
/* set the ptrace bit in the process flags. */
current->ptrace |= PT_PTRACED;
pt_succ_return(regs, 0);
goto out;
}
#ifndef ALLOW_INIT_TRACING
if (pid == 1) {
/* Can't dork with init. */
pt_error_return(regs, EPERM);
goto out;
}
#endif
read_lock(&tasklist_lock);
child = find_task_by_pid(pid);
if (child)
get_task_struct(child);
read_unlock(&tasklist_lock);
if (!child) {
pt_error_return(regs, ESRCH);
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;
}
if (!(test_thread_flag(TIF_32BIT)) &&
((request == PTRACE_READDATA64) ||
(request == PTRACE_WRITEDATA64) ||
(request == PTRACE_READTEXT64) ||
(request == PTRACE_WRITETEXT64) ||
(request == PTRACE_PEEKTEXT64) ||
(request == PTRACE_POKETEXT64) ||
(request == PTRACE_PEEKDATA64) ||
(request == PTRACE_POKEDATA64))) {
addr = regs->u_regs[UREG_G2];
addr2 = regs->u_regs[UREG_G3];
request -= 30; /* wheee... */
}
switch(request) {
case PTRACE_PEEKTEXT: /* read word at location addr. */
case PTRACE_PEEKDATA: {
unsigned long tmp64;
unsigned int tmp32;
int res, copied;
res = -EIO;
if (test_thread_flag(TIF_32BIT)) {
copied = access_process_vm(child, addr,
&tmp32, sizeof(tmp32), 0);
tmp64 = (unsigned long) tmp32;
if (copied == sizeof(tmp32))
res = 0;
} else {
copied = access_process_vm(child, addr,
&tmp64, sizeof(tmp64), 0);
if (copied == sizeof(tmp64))
res = 0;
}
if (res < 0)
pt_error_return(regs, -res);
else
pt_os_succ_return(regs, tmp64, (void __user *) data);
goto out_tsk;
}
case PTRACE_POKETEXT: /* write the word at location addr. */
case PTRACE_POKEDATA: {
unsigned long tmp64;
unsigned int tmp32;
int copied, res = -EIO;
if (test_thread_flag(TIF_32BIT)) {
tmp32 = data;
copied = access_process_vm(child, addr,
&tmp32, sizeof(tmp32), 1);
if (copied == sizeof(tmp32))
res = 0;
} else {
tmp64 = data;
copied = access_process_vm(child, addr,
&tmp64, sizeof(tmp64), 1);
if (copied == sizeof(tmp64))
res = 0;
}
if (res < 0)
pt_error_return(regs, -res);
else
pt_succ_return(regs, res);
goto out_tsk;
}
case PTRACE_GETREGS: {
struct pt_regs32 __user *pregs =
(struct pt_regs32 __user *) addr;
struct pt_regs *cregs = child->thread_info->kregs;
int rval;
if (__put_user(tstate_to_psr(cregs->tstate), (&pregs->psr)) ||
__put_user(cregs->tpc, (&pregs->pc)) ||
__put_user(cregs->tnpc, (&pregs->npc)) ||
__put_user(cregs->y, (&pregs->y))) {
pt_error_return(regs, EFAULT);
goto out_tsk;
}
for (rval = 1; rval < 16; rval++)
if (__put_user(cregs->u_regs[rval], (&pregs->u_regs[rval - 1]))) {
pt_error_return(regs, EFAULT);
goto out_tsk;
}
pt_succ_return(regs, 0);
#ifdef DEBUG_PTRACE
printk ("PC=%lx nPC=%lx o7=%lx\n", cregs->tpc, cregs->tnpc, cregs->u_regs [15]);
#endif
goto out_tsk;
}
case PTRACE_GETREGS64: {
struct pt_regs __user *pregs = (struct pt_regs __user *) addr;
struct pt_regs *cregs = child->thread_info->kregs;
unsigned long tpc = cregs->tpc;
int rval;
if ((child->thread_info->flags & _TIF_32BIT) != 0)
tpc &= 0xffffffff;
if (__put_user(cregs->tstate, (&pregs->tstate)) ||
__put_user(tpc, (&pregs->tpc)) ||
__put_user(cregs->tnpc, (&pregs->tnpc)) ||
__put_user(cregs->y, (&pregs->y))) {
pt_error_return(regs, EFAULT);
goto out_tsk;
}
for (rval = 1; rval < 16; rval++)
if (__put_user(cregs->u_regs[rval], (&pregs->u_regs[rval - 1]))) {
pt_error_return(regs, EFAULT);
goto out_tsk;
}
pt_succ_return(regs, 0);
#ifdef DEBUG_PTRACE
printk ("PC=%lx nPC=%lx o7=%lx\n", cregs->tpc, cregs->tnpc, cregs->u_regs [15]);
#endif
goto out_tsk;
}
case PTRACE_SETREGS: {
struct pt_regs32 __user *pregs =
(struct pt_regs32 __user *) addr;
struct pt_regs *cregs = child->thread_info->kregs;
unsigned int psr, pc, npc, y;
int i;
/* Must be careful, tracing process can only set certain
* bits in the psr.
*/
if (__get_user(psr, (&pregs->psr)) ||
__get_user(pc, (&pregs->pc)) ||
__get_user(npc, (&pregs->npc)) ||
__get_user(y, (&pregs->y))) {
pt_error_return(regs, EFAULT);
goto out_tsk;
}
cregs->tstate &= ~(TSTATE_ICC);
cregs->tstate |= psr_to_tstate_icc(psr);
if (!((pc | npc) & 3)) {
cregs->tpc = pc;
cregs->tnpc = npc;
}
cregs->y = y;
for (i = 1; i < 16; i++) {
if (__get_user(cregs->u_regs[i], (&pregs->u_regs[i-1]))) {
pt_error_return(regs, EFAULT);
goto out_tsk;
}
}
pt_succ_return(regs, 0);
goto out_tsk;
}
case PTRACE_SETREGS64: {
struct pt_regs __user *pregs = (struct pt_regs __user *) addr;
struct pt_regs *cregs = child->thread_info->kregs;
unsigned long tstate, tpc, tnpc, y;
int i;
/* Must be careful, tracing process can only set certain
* bits in the psr.
*/
if (__get_user(tstate, (&pregs->tstate)) ||
__get_user(tpc, (&pregs->tpc)) ||
__get_user(tnpc, (&pregs->tnpc)) ||
__get_user(y, (&pregs->y))) {
pt_error_return(regs, EFAULT);
goto out_tsk;
}
if ((child->thread_info->flags & _TIF_32BIT) != 0) {
tpc &= 0xffffffff;
tnpc &= 0xffffffff;
}
tstate &= (TSTATE_ICC | TSTATE_XCC);
cregs->tstate &= ~(TSTATE_ICC | TSTATE_XCC);
cregs->tstate |= tstate;
if (!((tpc | tnpc) & 3)) {
cregs->tpc = tpc;
cregs->tnpc = tnpc;
}
cregs->y = y;
for (i = 1; i < 16; i++) {
if (__get_user(cregs->u_regs[i], (&pregs->u_regs[i-1]))) {
pt_error_return(regs, EFAULT);
goto out_tsk;
}
}
pt_succ_return(regs, 0);
goto out_tsk;
}
case PTRACE_GETFPREGS: {
struct fps {
unsigned int regs[32];
unsigned int fsr;
unsigned int flags;
unsigned int extra;
unsigned int fpqd;
struct fq {
unsigned int insnaddr;
unsigned int insn;
} fpq[16];
};
struct fps __user *fps = (struct fps __user *) addr;
unsigned long *fpregs = child->thread_info->fpregs;
if (copy_to_user(&fps->regs[0], fpregs,
(32 * sizeof(unsigned int))) ||
__put_user(child->thread_info->xfsr[0], (&fps->fsr)) ||
__put_user(0, (&fps->fpqd)) ||
__put_user(0, (&fps->flags)) ||
__put_user(0, (&fps->extra)) ||
clear_user(&fps->fpq[0], 32 * sizeof(unsigned int))) {
pt_error_return(regs, EFAULT);
goto out_tsk;
}
pt_succ_return(regs, 0);
goto out_tsk;
}
case PTRACE_GETFPREGS64: {
struct fps {
unsigned int regs[64];
unsigned long fsr;
};
struct fps __user *fps = (struct fps __user *) addr;
unsigned long *fpregs = child->thread_info->fpregs;
if (copy_to_user(&fps->regs[0], fpregs,
(64 * sizeof(unsigned int))) ||
__put_user(child->thread_info->xfsr[0], (&fps->fsr))) {
pt_error_return(regs, EFAULT);
goto out_tsk;
}
pt_succ_return(regs, 0);
goto out_tsk;
}
case PTRACE_SETFPREGS: {
struct fps {
unsigned int regs[32];
unsigned int fsr;
unsigned int flags;
unsigned int extra;
unsigned int fpqd;
struct fq {
unsigned int insnaddr;
unsigned int insn;
} fpq[16];
};
struct fps __user *fps = (struct fps __user *) addr;
unsigned long *fpregs = child->thread_info->fpregs;
unsigned fsr;
if (copy_from_user(fpregs, &fps->regs[0],
(32 * sizeof(unsigned int))) ||
__get_user(fsr, (&fps->fsr))) {
pt_error_return(regs, EFAULT);
goto out_tsk;
}
child->thread_info->xfsr[0] &= 0xffffffff00000000UL;
child->thread_info->xfsr[0] |= fsr;
if (!(child->thread_info->fpsaved[0] & FPRS_FEF))
child->thread_info->gsr[0] = 0;
child->thread_info->fpsaved[0] |= (FPRS_FEF | FPRS_DL);
pt_succ_return(regs, 0);
goto out_tsk;
}
case PTRACE_SETFPREGS64: {
struct fps {
unsigned int regs[64];
unsigned long fsr;
};
struct fps __user *fps = (struct fps __user *) addr;
unsigned long *fpregs = child->thread_info->fpregs;
if (copy_from_user(fpregs, &fps->regs[0],
(64 * sizeof(unsigned int))) ||
__get_user(child->thread_info->xfsr[0], (&fps->fsr))) {
pt_error_return(regs, EFAULT);
goto out_tsk;
}
if (!(child->thread_info->fpsaved[0] & FPRS_FEF))
child->thread_info->gsr[0] = 0;
child->thread_info->fpsaved[0] |= (FPRS_FEF | FPRS_DL | FPRS_DU);
pt_succ_return(regs, 0);
goto out_tsk;
}
case PTRACE_READTEXT:
case PTRACE_READDATA: {
int res = ptrace_readdata(child, addr,
(char __user *)addr2, data);
if (res == data) {
pt_succ_return(regs, 0);
goto out_tsk;
}
if (res >= 0)
res = -EIO;
pt_error_return(regs, -res);
goto out_tsk;
}
case PTRACE_WRITETEXT:
case PTRACE_WRITEDATA: {
int res = ptrace_writedata(child, (char __user *) addr2,
addr, data);
if (res == data) {
pt_succ_return(regs, 0);
goto out_tsk;
}
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_info->kregs->tpc,
child->thread_info->kregs->tnpc);
#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;
}
child->exit_code = SIGKILL;
wake_up_process(child);
pt_succ_return(regs, 0);
goto out_tsk;
}
case PTRACE_SUNDETACH: { /* detach a process that was attached. */
int error = ptrace_detach(child, data);
if (error) {
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)
{
/* do the secure computing check first */
secure_computing(current_thread_info()->kregs->u_regs[UREG_G1]);
if (!test_thread_flag(TIF_SYSCALL_TRACE))
return;
if (!(current->ptrace & PT_PTRACED))
return;
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;
}
}
