[mirror_ubuntu-hirsute-kernel.git] / arch / sh / kernel / ptrace_32.c

/*
 * linux/arch/sh/kernel/ptrace.c
 *
 * Original x86 implementation:
 *	By Ross Biro 1/23/92
 *	edited by Linus Torvalds
 *
 * SuperH version:   Copyright (C) 1999, 2000  Kaz Kojima & Niibe Yutaka
 * Audit support: Yuichi Nakamura <ynakam@hitachisoft.jp>
 */
#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 <asm/uaccess.h>
#include <asm/pgtable.h>
#include <asm/system.h>
#include <asm/processor.h>
#include <asm/mmu_context.h>

/*
 * does not yet catch signals sent when the child dies.
 * in exit.c or in signal.c.
 */

/*
 * 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;
}

static void ptrace_disable_singlestep(struct task_struct *child)
{
	clear_tsk_thread_flag(child, TIF_SINGLESTEP);

	/*
	 * Ensure the UBC is not programmed at the next context switch.
	 *
	 * Normally this is not needed but there are sequences such as
	 * singlestep, signal delivery, and continue that leave the
	 * ubc_pc non-zero leading to spurious SIGTRAPs.
	 */
	if (child->thread.ubc_pc != 0) {
		ubc_usercnt -= 1;
		child->thread.ubc_pc = 0;
	}
}

/*
 * Called by kernel/ptrace.c when detaching..
 *
 * Make sure single step bits etc are not set.
 */
void ptrace_disable(struct task_struct *child)
{
	ptrace_disable_singlestep(child);
}

long arch_ptrace(struct task_struct *child, long request, long addr, long data)
{
	struct user * dummy = NULL;
	int ret;

	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:
		ret = generic_ptrace_peekdata(child, addr, data);
		break;

	/* 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.fpu)
					[(addr - (long)&dummy->fpu) >> 2];
		} else if (addr == (long) &dummy->u_fpvalid)
			tmp = !!tsk_used_math(child);
		else
			tmp = 0;
		ret = put_user(tmp, (unsigned long __user *)data);
		break;
	}

	/* when I and D space are separate, this will have to be fixed. */
	case PTRACE_POKETEXT: /* write the word at location addr. */
	case PTRACE_POKEDATA:
		ret = generic_ptrace_pokedata(child, addr, data);
		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.fpu)
				[(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_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);

		ptrace_disable_singlestep(child);

		child->exit_code = data;
		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;
		ptrace_disable_singlestep(child);
		child->exit_code = SIGKILL;
		wake_up_process(child);
		break;
	}

	case PTRACE_SINGLESTEP: {  /* set the trap flag. */
		long pc;
		struct pt_regs *regs = NULL;

		ret = -EIO;
		if (!valid_signal(data))
			break;
		clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
		if ((child->ptrace & PT_DTRACE) == 0) {
			/* Spurious delayed TF traps may occur */
			child->ptrace |= PT_DTRACE;
		}

		pc = get_stack_long(child, (long)&regs->pc);

		/* Next scheduling will set up UBC */
		if (child->thread.ubc_pc == 0)
			ubc_usercnt += 1;
		child->thread.ubc_pc = pc;

		set_tsk_thread_flag(child, TIF_SINGLESTEP);
		child->exit_code = data;
		/* give it a chance to run. */
		wake_up_process(child);
		ret = 0;
		break;
	}

#ifdef CONFIG_SH_DSP
	case PTRACE_GETDSPREGS: {
		unsigned long dp;

		ret = -EIO;
		dp = ((unsigned long) child) + THREAD_SIZE -
			 sizeof(struct pt_dspregs);
		if (*((int *) (dp - 4)) == SR_FD) {
			copy_to_user((void *)addr, (void *) dp,
				sizeof(struct pt_dspregs));
			ret = 0;
		}
		break;
	}

	case PTRACE_SETDSPREGS: {
		unsigned long dp;

		ret = -EIO;
		dp = ((unsigned long) child) + THREAD_SIZE -
			 sizeof(struct pt_dspregs);
		if (*((int *) (dp - 4)) == SR_FD) {
			copy_from_user((void *) dp, (void *)addr,
				sizeof(struct pt_dspregs));
			ret = 0;
		}
		break;
	}
#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, (unsigned long *) data)) {
			ret = -EFAULT;
			break;
		}
		break;
	}
#endif
	default:
		ret = ptrace_request(child, request, addr, data);
		break;
	}

	return ret;
}

asmlinkage void do_syscall_trace(struct pt_regs *regs, int entryexit)
{
	struct task_struct *tsk = current;

	if (unlikely(current->audit_context) && entryexit)
		audit_syscall_exit(AUDITSC_RESULT(regs->regs[0]),
				   regs->regs[0]);

	if (!test_thread_flag(TIF_SYSCALL_TRACE) &&
	    !test_thread_flag(TIF_SINGLESTEP))
		goto out;
	if (!(tsk->ptrace & PT_PTRACED))
		goto out;

	/* the 0x80 provides a way for the tracing parent to distinguish
	   between a syscall stop and SIGTRAP delivery */
	ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD) &&
				 !test_thread_flag(TIF_SINGLESTEP) ? 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 (tsk->exit_code) {
		send_sig(tsk->exit_code, tsk, 1);
		tsk->exit_code = 0;
	}

out:
	if (unlikely(current->audit_context) && !entryexit)
		audit_syscall_entry(AUDIT_ARCH_SH, regs->regs[3],
				    regs->regs[4], regs->regs[5],
				    regs->regs[6], regs->regs[7]);

}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* linux/arch/sh/kernel/ptrace.c
	3	*
	4	* Original x86 implementation:
	5	* By Ross Biro 1/23/92
	6	* edited by Linus Torvalds
	7	*
	8	* SuperH version: Copyright (C) 1999, 2000 Kaz Kojima & Niibe Yutaka
1322b9de	9	* Audit support: Yuichi Nakamura <ynakam@hitachisoft.jp>
1da177e4	10	*/
1da177e4 LT	11	#include <linux/kernel.h>
	12	#include <linux/sched.h>
	13	#include <linux/mm.h>
	14	#include <linux/smp.h>
1da177e4 LT	15	#include <linux/errno.h>
	16	#include <linux/ptrace.h>
	17	#include <linux/user.h>
	18	#include <linux/slab.h>
	19	#include <linux/security.h>
7ed20e1a	20	#include <linux/signal.h>
9432f968	21	#include <linux/io.h>
1322b9de	22	#include <linux/audit.h>
1da177e4 LT	23	#include <asm/uaccess.h>
	24	#include <asm/pgtable.h>
	25	#include <asm/system.h>
	26	#include <asm/processor.h>
	27	#include <asm/mmu_context.h>
	28
	29	/*
	30	* does not yet catch signals sent when the child dies.
	31	* in exit.c or in signal.c.
	32	*/
	33
	34	/*
	35	* This routine will get a word off of the process kernel stack.
	36	*/
	37	static inline int get_stack_long(struct task_struct *task, int offset)
	38	{
	39	unsigned char *stack;
	40
3cf0f4ec	41	stack = (unsigned char *)task_pt_regs(task);
1da177e4 LT	42	stack += offset;
	43	return (((int )stack));
	44	}
	45
	46	/*
	47	* This routine will put a word on the process kernel stack.
	48	*/
	49	static inline int put_stack_long(struct task_struct *task, int offset,
	50	unsigned long data)
	51	{
	52	unsigned char *stack;
	53
3cf0f4ec	54	stack = (unsigned char *)task_pt_regs(task);
1da177e4 LT	55	stack += offset;
	56	(unsigned long ) stack = data;
	57	return 0;
	58	}
	59
9432f968 SM	60	static void ptrace_disable_singlestep(struct task_struct *child)
	61	{
	62	clear_tsk_thread_flag(child, TIF_SINGLESTEP);
	63
	64	/*
	65	* Ensure the UBC is not programmed at the next context switch.
	66	*
	67	* Normally this is not needed but there are sequences such as
	68	* singlestep, signal delivery, and continue that leave the
	69	* ubc_pc non-zero leading to spurious SIGTRAPs.
	70	*/
	71	if (child->thread.ubc_pc != 0) {
	72	ubc_usercnt -= 1;
	73	child->thread.ubc_pc = 0;
	74	}
	75	}
	76
1da177e4 LT	77	/*
	78	* Called by kernel/ptrace.c when detaching..
	79	*
	80	* Make sure single step bits etc are not set.
	81	*/
	82	void ptrace_disable(struct task_struct *child)
	83	{
9432f968	84	ptrace_disable_singlestep(child);
1da177e4 LT	85	}
1da177e4 LT	86
481bed45	87	long arch_ptrace(struct task_struct *child, long request, long addr, long data)
1da177e4	88	{
1da177e4 LT	89	struct user * dummy = NULL;
	90	int ret;
	91
1da177e4 LT	92	switch (request) {
1da177e4 LT	93	/* when I and D space are separate, these will need to be fixed. */
9432f968	94	case PTRACE_PEEKTEXT: /* read word at location addr. */
76647323 AD	95	case PTRACE_PEEKDATA:
76647323 AD	96	ret = generic_ptrace_peekdata(child, addr, data);
662ae216	97	break;
1da177e4 LT	98
	99	/* read the word at location addr in the USER area. */
	100	case PTRACE_PEEKUSR: {
	101	unsigned long tmp;
	102
	103	ret = -EIO;
9432f968	104	if ((addr & 3) \|\| addr < 0 \|\|
1da177e4 LT	105	addr > sizeof(struct user) - 3)
	106	break;
	107
	108	if (addr < sizeof(struct pt_regs))
	109	tmp = get_stack_long(child, addr);
	110	else if (addr >= (long) &dummy->fpu &&
	111	addr < (long) &dummy->u_fpvalid) {
	112	if (!tsk_used_math(child)) {
	113	if (addr == (long)&dummy->fpu.fpscr)
	114	tmp = FPSCR_INIT;
	115	else
	116	tmp = 0;
	117	} else
	118	tmp = ((long *)&child->thread.fpu)
	119	[(addr - (long)&dummy->fpu) >> 2];
	120	} else if (addr == (long) &dummy->u_fpvalid)
	121	tmp = !!tsk_used_math(child);
	122	else
	123	tmp = 0;
e08f457c	124	ret = put_user(tmp, (unsigned long __user *)data);
1da177e4 LT	125	break;
	126	}
	127
	128	/* when I and D space are separate, this will have to be fixed. */
	129	case PTRACE_POKETEXT: /* write the word at location addr. */
	130	case PTRACE_POKEDATA:
f284ce72	131	ret = generic_ptrace_pokedata(child, addr, data);
1da177e4 LT	132	break;
	133
	134	case PTRACE_POKEUSR: /* write the word at location addr in the USER area */
	135	ret = -EIO;
9432f968	136	if ((addr & 3) \|\| addr < 0 \|\|
1da177e4 LT	137	addr > sizeof(struct user) - 3)
	138	break;
	139
	140	if (addr < sizeof(struct pt_regs))
	141	ret = put_stack_long(child, addr, data);
	142	else if (addr >= (long) &dummy->fpu &&
	143	addr < (long) &dummy->u_fpvalid) {
	144	set_stopped_child_used_math(child);
	145	((long *)&child->thread.fpu)
	146	[(addr - (long)&dummy->fpu) >> 2] = data;
	147	ret = 0;
	148	} else if (addr == (long) &dummy->u_fpvalid) {
	149	conditional_stopped_child_used_math(data, child);
	150	ret = 0;
	151	}
	152	break;
	153
	154	case PTRACE_SYSCALL: /* continue and stop at next (return from) syscall */
	155	case PTRACE_CONT: { /* restart after signal. */
	156	ret = -EIO;
7ed20e1a	157	if (!valid_signal(data))
1da177e4 LT	158	break;
	159	if (request == PTRACE_SYSCALL)
	160	set_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
	161	else
	162	clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
9432f968 SM	163
	164	ptrace_disable_singlestep(child);
	165
1da177e4 LT	166	child->exit_code = data;
	167	wake_up_process(child);
	168	ret = 0;
	169	break;
	170	}
	171
	172	/*
9432f968 SM	173	* make the child exit. Best I can do is send it a sigkill.
9432f968 SM	174	* perhaps it should be put in the status that it wants to
1da177e4 LT	175	* exit.
	176	*/
	177	case PTRACE_KILL: {
	178	ret = 0;
	179	if (child->exit_state == EXIT_ZOMBIE) /* already dead */
	180	break;
9432f968	181	ptrace_disable_singlestep(child);
1da177e4 LT	182	child->exit_code = SIGKILL;
	183	wake_up_process(child);
	184	break;
	185	}
	186
	187	case PTRACE_SINGLESTEP: { /* set the trap flag. */
	188	long pc;
e08f457c	189	struct pt_regs *regs = NULL;
1da177e4 LT	190
1da177e4 LT	191	ret = -EIO;
7ed20e1a	192	if (!valid_signal(data))
1da177e4 LT	193	break;
	194	clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
	195	if ((child->ptrace & PT_DTRACE) == 0) {
	196	/* Spurious delayed TF traps may occur */
	197	child->ptrace \|= PT_DTRACE;
	198	}
	199
e08f457c	200	pc = get_stack_long(child, (long)&regs->pc);
1da177e4 LT	201
	202	/* Next scheduling will set up UBC */
	203	if (child->thread.ubc_pc == 0)
	204	ubc_usercnt += 1;
	205	child->thread.ubc_pc = pc;
	206
9432f968	207	set_tsk_thread_flag(child, TIF_SINGLESTEP);
1da177e4 LT	208	child->exit_code = data;
	209	/* give it a chance to run. */
	210	wake_up_process(child);
	211	ret = 0;
	212	break;
	213	}
	214
1da177e4 LT	215	#ifdef CONFIG_SH_DSP
	216	case PTRACE_GETDSPREGS: {
	217	unsigned long dp;
	218
	219	ret = -EIO;
	220	dp = ((unsigned long) child) + THREAD_SIZE -
	221	sizeof(struct pt_dspregs);
	222	if (((int ) (dp - 4)) == SR_FD) {
09061850	223	copy_to_user((void )addr, (void ) dp,
1da177e4 LT	224	sizeof(struct pt_dspregs));
	225	ret = 0;
	226	}
	227	break;
	228	}
	229
	230	case PTRACE_SETDSPREGS: {
	231	unsigned long dp;
1da177e4 LT	232
	233	ret = -EIO;
	234	dp = ((unsigned long) child) + THREAD_SIZE -
	235	sizeof(struct pt_dspregs);
	236	if (((int ) (dp - 4)) == SR_FD) {
09061850	237	copy_from_user((void ) dp, (void )addr,
1da177e4 LT	238	sizeof(struct pt_dspregs));
	239	ret = 0;
	240	}
	241	break;
	242	}
3bc24a1a PM	243	#endif
	244	#ifdef CONFIG_BINFMT_ELF_FDPIC
	245	case PTRACE_GETFDPIC: {
	246	unsigned long tmp = 0;
	247
	248	switch (addr) {
	249	case PTRACE_GETFDPIC_EXEC:
	250	tmp = child->mm->context.exec_fdpic_loadmap;
	251	break;
	252	case PTRACE_GETFDPIC_INTERP:
	253	tmp = child->mm->context.interp_fdpic_loadmap;
	254	break;
	255	default:
	256	break;
	257	}
	258
	259	ret = 0;
	260	if (put_user(tmp, (unsigned long *) data)) {
	261	ret = -EFAULT;
	262	break;
	263	}
	264	break;
	265	}
1da177e4 LT	266	#endif
	267	default:
	268	ret = ptrace_request(child, request, addr, data);
	269	break;
	270	}
481bed45	271
1da177e4 LT	272	return ret;
	273	}
	274
1322b9de	275	asmlinkage void do_syscall_trace(struct pt_regs *regs, int entryexit)
1da177e4 LT	276	{
	277	struct task_struct *tsk = current;
	278
1322b9de YN	279	if (unlikely(current->audit_context) && entryexit)
	280	audit_syscall_exit(AUDITSC_RESULT(regs->regs[0]),
	281	regs->regs[0]);
	282
9432f968 SM	283	if (!test_thread_flag(TIF_SYSCALL_TRACE) &&
9432f968 SM	284	!test_thread_flag(TIF_SINGLESTEP))
1322b9de	285	goto out;
1da177e4	286	if (!(tsk->ptrace & PT_PTRACED))
1322b9de YN	287	goto out;
1322b9de YN	288
1da177e4 LT	289	/* the 0x80 provides a way for the tracing parent to distinguish
1da177e4 LT	290	between a syscall stop and SIGTRAP delivery */
9432f968 SM	291	ptrace_notify(SIGTRAP \| ((current->ptrace & PT_TRACESYSGOOD) &&
9432f968 SM	292	!test_thread_flag(TIF_SINGLESTEP) ? 0x80 : 0));
1da177e4 LT	293
	294	/*
	295	* this isn't the same as continuing with a signal, but it will do
	296	* for normal use. strace only continues with a signal if the
	297	* stopping signal is not SIGTRAP. -brl
	298	*/
	299	if (tsk->exit_code) {
	300	send_sig(tsk->exit_code, tsk, 1);
	301	tsk->exit_code = 0;
	302	}
1322b9de YN	303
	304	out:
	305	if (unlikely(current->audit_context) && !entryexit)
	306	audit_syscall_entry(AUDIT_ARCH_SH, regs->regs[3],
	307	regs->regs[4], regs->regs[5],
	308	regs->regs[6], regs->regs[7]);
	309
1da177e4	310	}