/*
* SuperH process tracing
*
* Copyright (C) 1999, 2000 Kaz Kojima & Niibe Yutaka
* Copyright (C) 2002 - 2009 Paul Mundt
*
* Audit support by Yuichi Nakamura <ynakam@hitachisoft.jp>
*
* 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/kernel.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/smp.h>
#include <linux/errno.h>
#include <linux/ptrace.h>
#include <linux/user.h>
#include <linux/slab.h>
#include <linux/security.h>
#include <linux/signal.h>
#include <linux/io.h>
#include <linux/audit.h>
#include <linux/seccomp.h>
#include <linux/tracehook.h>
#include <linux/elf.h>
#include <linux/regset.h>
#include <linux/hw_breakpoint.h>
#include <asm/uaccess.h>
#include <asm/pgtable.h>
#include <asm/system.h>
#include <asm/processor.h>
#include <asm/mmu_context.h>
#include <asm/syscalls.h>
#include <asm/fpu.h>
#define CREATE_TRACE_POINTS
#include <trace/events/syscalls.h>
/*
* This routine will get a word off of the process kernel stack.
*/
static inline int get_stack_long(struct task_struct *task, int offset)
{
unsigned char *stack;
stack = (unsigned char *)task_pt_regs(task);
stack += offset;
return (*((int *)stack));
}
/*
* This routine will put a word on the process kernel stack.
*/
static inline int put_stack_long(struct task_struct *task, int offset,
unsigned long data)
{
unsigned char *stack;
stack = (unsigned char *)task_pt_regs(task);
stack += offset;
*(unsigned long *) stack = data;
return 0;
}
void ptrace_triggered(struct perf_event *bp, int nmi,
struct perf_sample_data *data, struct pt_regs *regs)
{
struct perf_event_attr attr;
/*
* Disable the breakpoint request here since ptrace has defined a
* one-shot behaviour for breakpoint exceptions.
*/
attr = bp->attr;
attr.disabled = true;
modify_user_hw_breakpoint(bp, &attr);
}
static int set_single_step(struct task_struct *tsk, unsigned long addr)
{
struct thread_struct *thread = &tsk->thread;
struct perf_event *bp;
struct perf_event_attr attr;
bp = thread->ptrace_bps[0];
if (!bp) {
hw_breakpoint_init(&attr);
attr.bp_addr = addr;
attr.bp_len = HW_BREAKPOINT_LEN_2;
attr.bp_type = HW_BREAKPOINT_R;
bp = register_user_hw_breakpoint(&attr, ptrace_triggered, tsk);
if (IS_ERR(bp))
return PTR_ERR(bp);
thread->ptrace_bps[0] = bp;
} else {
int err;
attr = bp->attr;
attr.bp_addr = addr;
err = modify_user_hw_breakpoint(bp, &attr);
if (unlikely(err))
return err;
}
return 0;
}
void user_enable_single_step(struct task_struct *child)
{
unsigned long pc = get_stack_long(child, offsetof(struct pt_regs, pc));
set_tsk_thread_flag(child, TIF_SINGLESTEP);
set_single_step(child, pc);
}
void user_disable_single_step(struct task_struct *child)
{
clear_tsk_thread_flag(child, TIF_SINGLESTEP);
}
/*
* Called by kernel/ptrace.c when detaching..
*
* Make sure single step bits etc are not set.
*/
void ptrace_disable(struct task_struct *child)
{
user_disable_single_step(child);
}
static int genregs_get(struct task_struct *target,
const struct user_regset *regset,
unsigned int pos, unsigned int count,
void *kbuf, void __user *ubuf)
{
const struct pt_regs *regs = task_pt_regs(target);
int ret;
ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
regs->regs,
0, 16 * sizeof(unsigned long));
if (!ret)
/* PC, PR, SR, GBR, MACH, MACL, TRA */
ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
®s->pc,
offsetof(struct pt_regs, pc),
sizeof(struct pt_regs));
if (!ret)
ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
sizeof(struct pt_regs), -1);
return ret;
}
static int genregs_set(struct task_struct *target,
const struct user_regset *regset,
unsigned int pos, unsigned int count,
const void *kbuf, const void __user *ubuf)
{
struct pt_regs *regs = task_pt_regs(target);
int ret;
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
regs->regs,
0, 16 * sizeof(unsigned long));
if (!ret && count > 0)
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
®s->pc,
offsetof(struct pt_regs, pc),
sizeof(struct pt_regs));
if (!ret)
ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
sizeof(struct pt_regs), -1);
return ret;
}
#ifdef CONFIG_SH_FPU
int fpregs_get(struct task_struct *target,
const struct user_regset *regset,
unsigned int pos, unsigned int count,
void *kbuf, void __user *ubuf)
{
int ret;
ret = init_fpu(target);
if (ret)
return ret;
if ((boot_cpu_data.flags & CPU_HAS_FPU))
return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
&target->thread.xstate->hardfpu, 0, -1);
return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
&target->thread.xstate->softfpu, 0, -1);
}
static int fpregs_set(struct task_struct *target,
const struct user_regset *regset,
unsigned int pos, unsigned int count,
const void *kbuf, const void __user *ubuf)
{
int ret;
ret = init_fpu(target);
if (ret)
return ret;
set_stopped_child_used_math(target);
if ((boot_cpu_data.flags & CPU_HAS_FPU))
return user_regset_copyin(&pos, &count, &kbuf, &ubuf,
&target->thread.xstate->hardfpu, 0, -1);
return user_regset_copyin(&pos, &count, &kbuf, &ubuf,
&target->thread.xstate->softfpu, 0, -1);
}
static int fpregs_active(struct task_struct *target,
const struct user_regset *regset)
{
return tsk_used_math(target) ? regset->n : 0;
}
#endif
#ifdef CONFIG_SH_DSP
static int dspregs_get(struct task_struct *target,
const struct user_regset *regset,
unsigned int pos, unsigned int count,
void *kbuf, void __user *ubuf)
{
const struct pt_dspregs *regs =
(struct pt_dspregs *)&target->thread.dsp_status.dsp_regs;
int ret;
ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, regs,
0, sizeof(struct pt_dspregs));
if (!ret)
ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
sizeof(struct pt_dspregs), -1);
return ret;
}
static int dspregs_set(struct task_struct *target,
const struct user_regset *regset,
unsigned int pos, unsigned int count,
const void *kbuf, const void __user *ubuf)
{
struct pt_dspregs *regs =
(struct pt_dspregs *)&target->thread.dsp_status.dsp_regs;
int ret;
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, regs,
0, sizeof(struct pt_dspregs));
if (!ret)
ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
sizeof(struct pt_dspregs), -1);
return ret;
}
static int dspregs_active(struct task_struct *target,
const struct user_regset *regset)
{
struct pt_regs *regs = task_pt_regs(target);
return regs->sr & SR_DSP ? regset->n : 0;
}
#endif
/*
* These are our native regset flavours.
*/
enum sh_regset {
REGSET_GENERAL,
#ifdef CONFIG_SH_FPU
REGSET_FPU,
#endif
#ifdef CONFIG_SH_DSP
REGSET_DSP,
#endif
};
static const struct user_regset sh_regsets[] = {
/*
* Format is:
* R0 --> R15
* PC, PR, SR, GBR, MACH, MACL, TRA
*/
[REGSET_GENERAL] = {
.core_note_type = NT_PRSTATUS,
.n = ELF_NGREG,
.size = sizeof(long),
.align = sizeof(long),
.get = genregs_get,
.set = genregs_set,
},
#ifdef CONFIG_SH_FPU
[REGSET_FPU] = {
.core_note_type = NT_PRFPREG,
.n = sizeof(struct user_fpu_struct) / sizeof(long),
.size = sizeof(long),
.align = sizeof(long),
.get = fpregs_get,
.set = fpregs_set,
.active = fpregs_active,
},
#endif
#ifdef CONFIG_SH_DSP
[REGSET_DSP] = {
.n = sizeof(struct pt_dspregs) / sizeof(long),
.size = sizeof(long),
.align = sizeof(long),
.get = dspregs_get,
.set = dspregs_set,
.active = dspregs_active,
},
#endif
};
static const struct user_regset_view user_sh_native_view = {
.name = "sh",
.e_machine = EM_SH,
.regsets = sh_regsets,
.n = ARRAY_SIZE(sh_regsets),
};
const struct user_regset_view *task_user_regset_view(struct task_struct *task)
{
return &user_sh_native_view;
}
long arch_ptrace(struct task_struct *child, long request, long addr, long data)
{
struct user * dummy = NULL;
unsigned long __user *datap = (unsigned long __user *)data;
int ret;
switch (request) {
/* read the word at location addr in the USER area. */
case PTRACE_PEEKUSR: {
unsigned long tmp;
ret = -EIO;
if ((addr & 3) || addr < 0 ||
addr > sizeof(struct user) - 3)
break;
if (addr < sizeof(struct pt_regs))
tmp = get_stack_long(child, addr);
else if (addr >= (long) &dummy->fpu &&
addr < (long) &dummy->u_fpvalid) {
if (!tsk_used_math(child)) {
if (addr == (long)&dummy->fpu.fpscr)
tmp = FPSCR_INIT;
else
tmp = 0;
} else
tmp = ((long *)child->thread.xstate)
[(addr - (long)&dummy->fpu) >> 2];
} else if (addr == (long) &dummy->u_fpvalid)
tmp = !!tsk_used_math(child);
else if (addr == PT_TEXT_ADDR)
tmp = child->mm->start_code;
else if (addr == PT_DATA_ADDR)
tmp = child->mm->start_data;
else if (addr == PT_TEXT_END_ADDR)
tmp = child->mm->end_code;
else if (addr == PT_TEXT_LEN)
tmp = child->mm->end_code - child->mm->start_code;
else
tmp = 0;
ret = put_user(tmp, datap);
break;
}
case PTRACE_POKEUSR: /* write the word at location addr in the USER area */
ret = -EIO;
if ((addr & 3) || addr < 0 ||
addr > sizeof(struct user) - 3)
break;
if (addr < sizeof(struct pt_regs))
ret = put_stack_long(child, addr, data);
else if (addr >= (long) &dummy->fpu &&
addr < (long) &dummy->u_fpvalid) {
set_stopped_child_used_math(child);
((long *)child->thread.xstate)
[(addr - (long)&dummy->fpu) >> 2] = data;
ret = 0;
} else if (addr == (long) &dummy->u_fpvalid) {
conditional_stopped_child_used_math(data, child);
ret = 0;
}
break;
case PTRACE_GETREGS:
return copy_regset_to_user(child, &user_sh_native_view,
REGSET_GENERAL,
0, sizeof(struct pt_regs),
(void __user *)data);
case PTRACE_SETREGS:
return copy_regset_from_user(child, &user_sh_native_view,
REGSET_GENERAL,
0, sizeof(struct pt_regs),
(const void __user *)data);
#ifdef CONFIG_SH_FPU
case PTRACE_GETFPREGS:
return copy_regset_to_user(child, &user_sh_native_view,
REGSET_FPU,
0, sizeof(struct user_fpu_struct),
(void __user *)data);
case PTRACE_SETFPREGS:
return copy_regset_from_user(child, &user_sh_native_view,
REGSET_FPU,
0, sizeof(struct user_fpu_struct),
(const void __user *)data);
#endif
#ifdef CONFIG_SH_DSP
case PTRACE_GETDSPREGS:
return copy_regset_to_user(child, &user_sh_native_view,
REGSET_DSP,
0, sizeof(struct pt_dspregs),
(void __user *)data);
case PTRACE_SETDSPREGS:
return copy_regset_from_user(child, &user_sh_native_view,
REGSET_DSP,
0, sizeof(struct pt_dspregs),
(const void __user *)data);
#endif
#ifdef CONFIG_BINFMT_ELF_FDPIC
case PTRACE_GETFDPIC: {
unsigned long tmp = 0;
switch (addr) {
case PTRACE_GETFDPIC_EXEC:
tmp = child->mm->context.exec_fdpic_loadmap;
break;
case PTRACE_GETFDPIC_INTERP:
tmp = child->mm->context.interp_fdpic_loadmap;
break;
default:
break;
}
ret = 0;
if (put_user(tmp, datap)) {
ret = -EFAULT;
break;
}
break;
}
#endif
default:
ret = ptrace_request(child, request, addr, data);
break;
}
return ret;
}
static inline int audit_arch(void)
{
int arch = EM_SH;
#ifdef CONFIG_CPU_LITTLE_ENDIAN
arch |= __AUDIT_ARCH_LE;
#endif
return arch;
}
asmlinkage long do_syscall_trace_enter(struct pt_regs *regs)
{
long ret = 0;
secure_computing(regs->regs[0]);
if (test_thread_flag(TIF_SYSCALL_TRACE) &&
tracehook_report_syscall_entry(regs))
/*
* Tracing decided this syscall should not happen.
* We'll return a bogus call number to get an ENOSYS
* error, but leave the original number in regs->regs[0].
*/
ret = -1L;
if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
trace_sys_enter(regs, regs->regs[0]);
if (unlikely(current->audit_context))
audit_syscall_entry(audit_arch(), regs->regs[3],
regs->regs[4], regs->regs[5],
regs->regs[6], regs->regs[7]);
return ret ?: regs->regs[0];
}
asmlinkage void do_syscall_trace_leave(struct pt_regs *regs)
{
int step;
if (unlikely(current->audit_context))
audit_syscall_exit(AUDITSC_RESULT(regs->regs[0]),
regs->regs[0]);
if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
trace_sys_exit(regs, regs->regs[0]);
step = test_thread_flag(TIF_SINGLESTEP);
if (step || test_thread_flag(TIF_SYSCALL_TRACE))
tracehook_report_syscall_exit(regs, step);
}
