sparcv8leon3-generic-qemu: stack overflow during register spilling causes Data Access Error in kernel

[badochov]

The program below causes kernel to access location past mapped ustack during register spilling.

#include <stdio.h>


void a(int i) {
	if (i != 0) {
		b(i - 1); 
	}
	printf("A\n");
}

void b(int i) {
	if (i != 0) {
		a(i - 1); 
	}
	printf("B\n");
}


int main(void)
{
	a(34);

	return 0;
}

Error:

qemu: fatal: Trap 0x29 (Data Access Error) while interrupts disabled, Error state
pc: c0006f34  npc: c0006f38
%g0-7: 00000000 00004001 00000008 00000400 00000034 00000000 00000000 00001004
%o0-7: 00000001 00004000 00000002 c002a000 c015cc00 c002a000 7fffefa8 00012540 
%l0-7: f39000c5 c0014c60 c0014c64 c0006800 00002000 c001c7fc c001f040 c015fd40 
%i0-7: 00000001 00004000 00000002 7ffff058 00000001 c015cc00 7ffff008 00012588 
%f00:  0000000000000000 0000000000000000 0000000000000000 0000000000000000
%f08:  0000000000000000 0000000000000000 0000000000000000 0000000000000000
%f16:  0000000000000000 0000000000000000 0000000000000000 0000000000000000
%f24:  0000000000000000 0000000000000000 0000000000000000 0000000000000000
psr: f3900085 (icc: N--C SPE: S--) wim: 00000008
fsr: 00000000 y: 00000000

pc points to sparcv8leon3/_traps.S:627