sparc: Fix regset register window handling.

We have to adjust 'reg_window' down by 16 becuase the 'pos' iterator
we'll use to index into the stack slots will be between 16 and 32.

Signed-off-by: David S. Miller <davem@davemloft.net>

arch/sparc/kernel/ptrace_32.c

@@ -65,6 +65,7 @@ static int genregs32_get(struct task_struct *target,
 			*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++]))
 				return -EFAULT;
@@ -76,6 +77,7 @@ static int genregs32_get(struct task_struct *target,
 		}
 
 		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++))
@@ -141,6 +143,7 @@ static int genregs32_set(struct task_struct *target,
 			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;
@@ -153,6 +156,7 @@ static int genregs32_set(struct task_struct *target,
 		}
 
 		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++]))

arch/sparc/kernel/ptrace_64.c

@@ -492,6 +492,7 @@ static int genregs32_get(struct task_struct *target,
 			*k++ = regs->u_regs[pos++];
 
 		reg_window = (compat_ulong_t __user *) regs->u_regs[UREG_I6];
+		reg_window -= 16;
 		if (target == current) {
 			for (; count > 0 && pos < 32; count--) {
 				if (get_user(*k++, &reg_window[pos++]))
@@ -516,6 +517,7 @@ static int genregs32_get(struct task_struct *target,
 		}
 
 		reg_window = (compat_ulong_t __user *) regs->u_regs[UREG_I6];
+		reg_window -= 16;
 		if (target == current) {
 			for (; count > 0 && pos < 32; count--) {
 				if (get_user(reg, &reg_window[pos++]) ||
@@ -599,6 +601,7 @@ static int genregs32_set(struct task_struct *target,
 			regs->u_regs[pos++] = *k++;
 
 		reg_window = (compat_ulong_t __user *) regs->u_regs[UREG_I6];
+		reg_window -= 16;
 		if (target == current) {
 			for (; count > 0 && pos < 32; count--) {
 				if (put_user(*k++, &reg_window[pos++]))
@@ -625,6 +628,7 @@ static int genregs32_set(struct task_struct *target,
 		}
 
 		reg_window = (compat_ulong_t __user *) regs->u_regs[UREG_I6];
+		reg_window -= 16;
 		if (target == current) {
 			for (; count > 0 && pos < 32; count--) {
 				if (get_user(reg, u++) ||