linux/arch/sparc64/kernel/ptrace.c
David S. Miller fb65b9619b [PATCH] sparc: Fix PTRACE_CONT bogosity
SunOS aparently had this weird PTRACE_CONT semantic which
we copied.  If the addr argument is something other than
1, it sets the process program counter to whatever that
value is.

This is different from every other Linux architecture, which
don't do anything with the addr and data args.

This difference in particular breaks the Linux native GDB support
for fork and vfork tracing on sparc and sparc64.

There is no interest in running SunOS binaries using this weird
PTRACE_CONT behavior, so just delete it so we behave like other
platforms do.

Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-04-17 18:03:11 -07:00

628 lines
16 KiB
C

/* 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 <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 */
}
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 flush_and_out;
}
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 flush_and_out;
}
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 flush_and_out;
}
if (res >= 0)
res = -EIO;
pt_error_return(regs, -res);
goto flush_and_out;
}
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 flush_and_out;
}
if (res >= 0)
res = -EIO;
pt_error_return(regs, -res);
goto flush_and_out;
}
case PTRACE_SYSCALL: /* continue and stop at (return from) syscall */
addr = 1;
case PTRACE_CONT: { /* restart after signal. */
if (data > _NSIG) {
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;
}
}
flush_and_out:
{
unsigned long va;
if (tlb_type == cheetah || tlb_type == cheetah_plus) {
for (va = 0; va < (1 << 16); va += (1 << 5))
spitfire_put_dcache_tag(va, 0x0);
/* No need to mess with I-cache on Cheetah. */
} else {
for (va = 0; va < L1DCACHE_SIZE; va += 32)
spitfire_put_dcache_tag(va, 0x0);
if (request == PTRACE_PEEKTEXT ||
request == PTRACE_POKETEXT ||
request == PTRACE_READTEXT ||
request == PTRACE_WRITETEXT) {
for (va = 0; va < (PAGE_SIZE << 1); va += 32)
spitfire_put_icache_tag(va, 0x0);
__asm__ __volatile__("flush %g6");
}
}
}
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;
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;
}
}