Add a test for arm privilege escalation

This commit is contained in:
lazymio 2022-01-04 20:30:07 +01:00
parent 085ee07c73
commit 7dc858d03d
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@ -398,6 +398,52 @@ static void test_arm_thumb_smlabb()
OK(uc_close(uc));
}
static void test_arm_not_allow_privilege_escalation()
{
uc_engine *uc;
int r_cpsr, r_sp, r_spsr, r_lr;
// E3C6601F : BIC r6, r6, #&1F
// E3866013 : ORR r6, r6, #&13
// E121F006 : MSR cpsr_c, r6 ; switch to SVC32 (should be ineffective
// from USR32) E1A00000 : MOV r0,r0 EF000011 : SWI OS_Exit
char code[] = "\x1f\x60\xc6\xe3\x13\x60\x86\xe3\x06\xf0\x21\xe1\x00\x00\xa0"
"\xe1\x11\x00\x00\xef";
uc_common_setup(&uc, UC_ARCH_ARM, UC_MODE_ARM, code, sizeof(code) - 1,
UC_CPU_ARM_CORTEX_A9);
// https://www.keil.com/pack/doc/CMSIS/Core_A/html/group__CMSIS__CPSR.html
r_cpsr = 0x40000013; // SVC32
OK(uc_reg_write(uc, UC_ARM_REG_CPSR, &r_cpsr));
r_spsr = 0x40000013;
OK(uc_reg_write(uc, UC_ARM_REG_SPSR, &r_spsr));
r_sp = 0x12345678;
OK(uc_reg_write(uc, UC_ARM_REG_SP, &r_sp));
r_lr = 0x00102220;
OK(uc_reg_write(uc, UC_ARM_REG_LR, &r_lr));
r_cpsr = 0x40000010; // USR32
OK(uc_reg_write(uc, UC_ARM_REG_CPSR, &r_cpsr));
r_sp = 0x0010000;
OK(uc_reg_write(uc, UC_ARM_REG_SP, &r_sp));
r_lr = 0x0001234;
OK(uc_reg_write(uc, UC_ARM_REG_LR, &r_lr));
uc_assert_err(
UC_ERR_EXCEPTION,
uc_emu_start(uc, code_start, code_start + sizeof(code) - 1, 0, 0));
OK(uc_reg_read(uc, UC_ARM_REG_CPSR, &r_cpsr));
OK(uc_reg_read(uc, UC_ARM_REG_SP, &r_sp));
OK(uc_reg_read(uc, UC_ARM_REG_LR, &r_lr));
OK((r_cpsr & ((1 << 4) - 1)) == 0); // Stay in USR32
OK(r_lr == 0x1234);
OK(r_sp == 0x10000);
OK(uc_close(uc));
}
TEST_LIST = {{"test_arm_nop", test_arm_nop},
{"test_arm_thumb_sub", test_arm_thumb_sub},
{"test_armeb_sub", test_armeb_sub},
@ -410,4 +456,6 @@ TEST_LIST = {{"test_arm_nop", test_arm_nop},
{"test_arm_usr32_to_svc32", test_arm_usr32_to_svc32},
{"test_arm_v8", test_arm_v8},
{"test_arm_thumb_smlabb", test_arm_thumb_smlabb},
{"test_arm_not_allow_privilege_escalation",
test_arm_not_allow_privilege_escalation},
{NULL, NULL}};