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#include "../multiarch/noexec.c.inc"
static void *arch_mcontext_pc(const mcontext_t *ctx)
{
return (void *)ctx->__gregs[REG_PC];
}
static int arch_mcontext_arg(const mcontext_t *ctx)
{
return ctx->__gregs[REG_A0];
}
static void arch_flush(void *p, int len)
{
__builtin___clear_cache(p, p + len);
}
extern char noexec_1[];
extern char noexec_2[];
extern char noexec_end[];
asm(".option push\n"
".option norvc\n"
"noexec_1:\n"
" li a0,1\n" /* a0 is 0 on entry, set 1. */
"noexec_2:\n"
" li a0,2\n" /* a0 is 0/1; set 2. */
" ret\n"
"noexec_end:\n"
".option pop");
int main(void)
{
struct noexec_test noexec_tests[] = {
{
.name = "fallthrough",
.test_code = noexec_1,
.test_len = noexec_end - noexec_1,
.page_ofs = noexec_1 - noexec_2,
.entry_ofs = noexec_1 - noexec_2,
.expected_si_ofs = 0,
.expected_pc_ofs = 0,
.expected_arg = 1,
},
{
.name = "jump",
.test_code = noexec_1,
.test_len = noexec_end - noexec_1,
.page_ofs = noexec_1 - noexec_2,
.entry_ofs = 0,
.expected_si_ofs = 0,
.expected_pc_ofs = 0,
.expected_arg = 0,
},
{
.name = "fallthrough [cross]",
.test_code = noexec_1,
.test_len = noexec_end - noexec_1,
.page_ofs = noexec_1 - noexec_2 - 2,
.entry_ofs = noexec_1 - noexec_2 - 2,
.expected_si_ofs = 0,
.expected_pc_ofs = -2,
.expected_arg = 1,
},
{
.name = "jump [cross]",
.test_code = noexec_1,
.test_len = noexec_end - noexec_1,
.page_ofs = noexec_1 - noexec_2 - 2,
.entry_ofs = -2,
.expected_si_ofs = 0,
.expected_pc_ofs = -2,
.expected_arg = 0,
},
};
return test_noexec(noexec_tests,
sizeof(noexec_tests) / sizeof(noexec_tests[0]));
}
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