Commit cf51e129 authored by Al Viro's avatar Al Viro
Browse files

sparc32: fix register window handling in genregs32_[gs]et() 



It needs access_process_vm() if the traced process does not share
mm with the caller.  Solution is similar to what sparc64 does.
Note that genregs32_set() is only ever called with pos being 0
or 32 * sizeof(u32) (the latter - as part of PTRACE_SETREGS
handling).

Cc: stable@kernel.org
Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent 142cd252

arch/sparc/kernel/ptrace_32.c

+98 −130
Original line number Diff line number Diff line
@@ -46,82 +46,79 @@ enum sparc_regset { 
	REGSET_FP,

};



static int genregs32_get(struct task_struct *target,

			 const struct user_regset *regset,

			 unsigned int pos, unsigned int count,

			 void *kbuf, void __user *ubuf)

static int regwindow32_get(struct task_struct *target,

			   const struct pt_regs *regs,

			   u32 *uregs)

{

	const struct pt_regs *regs = target->thread.kregs;

	unsigned long __user *reg_window;

	unsigned long *k = kbuf;

	unsigned long __user *u = ubuf;

	unsigned long reg;



	if (target == current)

		flush_user_windows();



	pos /= sizeof(reg);

	count /= sizeof(reg);

	unsigned long reg_window = regs->u_regs[UREG_I6];

	int size = 16 * sizeof(u32);



	if (kbuf) {

		for (; count > 0 && pos < 16; count--)

			*k++ = regs->u_regs[pos++];



		reg_window = (unsigned long __user *) regs->u_regs[UREG_I6];

		reg_window -= 16;

		for (; count > 0 && pos < 32; count--) {

			if (get_user(*k++, &reg_window[pos++]))

	if (target == current) {

		if (copy_from_user(uregs, (void __user *)reg_window, size))

			return -EFAULT;

		}

	} else {

		for (; count > 0 && pos < 16; count--) {

			if (put_user(regs->u_regs[pos++], u++))

		if (access_process_vm(target, reg_window, uregs, size,

				      FOLL_FORCE) != size)

			return -EFAULT;

	}

	return 0;

}



static int regwindow32_set(struct task_struct *target,

			   const struct pt_regs *regs,

			   u32 *uregs)

{

	unsigned long reg_window = regs->u_regs[UREG_I6];

	int size = 16 * sizeof(u32);



		reg_window = (unsigned long __user *) regs->u_regs[UREG_I6];

		reg_window -= 16;

		for (; count > 0 && pos < 32; count--) {

			if (get_user(reg, &reg_window[pos++]) ||

			    put_user(reg, u++))

	if (target == current) {

		if (copy_to_user((void __user *)reg_window, uregs, size))

			return -EFAULT;

	} else {

		if (access_process_vm(target, reg_window, uregs, size,

				      FOLL_FORCE | FOLL_WRITE) != size)

			return -EFAULT;

	}

	return 0;

}

	while (count > 0) {

		switch (pos) {

		case 32: /* PSR */

			reg = regs->psr;

			break;

		case 33: /* PC */

			reg = regs->pc;

			break;

		case 34: /* NPC */

			reg = regs->npc;

			break;

		case 35: /* Y */

			reg = regs->y;

			break;

		case 36: /* WIM */

		case 37: /* TBR */

			reg = 0;

			break;

		default:

			goto finish;

		}



		if (kbuf)

			*k++ = reg;

		else if (put_user(reg, u++))

static int genregs32_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 = target->thread.kregs;

	u32 uregs[16];

	int ret;



	if (target == current)

		flush_user_windows();



	ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,

				  regs->u_regs,

				  0, 16 * sizeof(u32));

	if (ret || !count)

		return ret;



	if (pos < 32 * sizeof(u32)) {

		if (regwindow32_get(target, regs, uregs))

			return -EFAULT;

		pos++;

		count--;

		ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,

					  uregs,

					  16 * sizeof(u32), 32 * sizeof(u32));

		if (ret || !count)

			return ret;

	}

finish:

	pos *= sizeof(reg);

	count *= sizeof(reg);



	return user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,

					38 * sizeof(reg), -1);

	uregs[0] = regs->psr;

	uregs[1] = regs->pc;

	uregs[2] = regs->npc;

	uregs[3] = regs->y;

	uregs[4] = 0;	/* WIM */

	uregs[5] = 0;	/* TBR */

	return user_regset_copyout(&pos, &count, &kbuf, &ubuf,

				  uregs,

				  32 * sizeof(u32), 38 * sizeof(u32));

}



static int genregs32_set(struct task_struct *target,
@@ -130,82 +127,53 @@ static int genregs32_set(struct task_struct *target, 
			 const void *kbuf, const void __user *ubuf)

{

	struct pt_regs *regs = target->thread.kregs;

	unsigned long __user *reg_window;

	const unsigned long *k = kbuf;

	const unsigned long __user *u = ubuf;

	unsigned long reg;

	u32 uregs[16];

	u32 psr;

	int ret;



	if (target == current)

		flush_user_windows();



	pos /= sizeof(reg);

	count /= sizeof(reg);



	if (kbuf) {

		for (; count > 0 && pos < 16; count--)

			regs->u_regs[pos++] = *k++;



		reg_window = (unsigned long __user *) regs->u_regs[UREG_I6];

		reg_window -= 16;

		for (; count > 0 && pos < 32; count--) {

			if (put_user(*k++, &reg_window[pos++]))

				return -EFAULT;

		}

	} else {

		for (; count > 0 && pos < 16; count--) {

			if (get_user(reg, u++))

				return -EFAULT;

			regs->u_regs[pos++] = reg;

		}

	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,

				 regs->u_regs,

				 0, 16 * sizeof(u32));

	if (ret || !count)

		return ret;



		reg_window = (unsigned long __user *) regs->u_regs[UREG_I6];

		reg_window -= 16;

		for (; count > 0 && pos < 32; count--) {

			if (get_user(reg, u++) ||

			    put_user(reg, &reg_window[pos++]))

	if (pos < 32 * sizeof(u32)) {

		if (regwindow32_get(target, regs, uregs))

			return -EFAULT;

		}

	}

	while (count > 0) {

		unsigned long psr;



		if (kbuf)

			reg = *k++;

		else if (get_user(reg, u++))

		ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,

					 uregs,

					 16 * sizeof(u32), 32 * sizeof(u32));

		if (ret)

			return ret;

		if (regwindow32_set(target, regs, uregs))

			return -EFAULT;



		switch (pos) {

		case 32: /* PSR */

			psr = regs->psr;

			psr &= ~(PSR_ICC | PSR_SYSCALL);

			psr |= (reg & (PSR_ICC | PSR_SYSCALL));

			regs->psr = psr;

			break;

		case 33: /* PC */

			regs->pc = reg;

			break;

		case 34: /* NPC */

			regs->npc = reg;

			break;

		case 35: /* Y */

			regs->y = reg;

			break;

		case 36: /* WIM */

		case 37: /* TBR */

			break;

		default:

			goto finish;

		if (!count)

			return 0;

	}



		pos++;

		count--;

	}

finish:

	pos *= sizeof(reg);

	count *= sizeof(reg);



	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,

				 &psr,

				 32 * sizeof(u32), 33 * sizeof(u32));

	if (ret)

		return ret;

	regs->psr = (regs->psr & ~(PSR_ICC | PSR_SYSCALL)) |

		    (psr & (PSR_ICC | PSR_SYSCALL));

	if (!count)

		return 0;

	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,

				 &regs->pc,

				 33 * sizeof(u32), 34 * sizeof(u32));

	if (ret || !count)

		return ret;

	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,

				 &regs->y,

				 34 * sizeof(u32), 35 * sizeof(u32));

	if (ret || !count)

		return ret;

	return user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,

					 38 * sizeof(reg), -1);

					 35 * sizeof(u32), 38 * sizeof(u32));

}



static int fpregs32_get(struct task_struct *target,

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