171 lines
3.4 KiB
C
171 lines
3.4 KiB
C
// SPDX-License-Identifier: GPL-2.0+
|
|
/*
|
|
* Copyright 2018, Michael Ellerman, IBM Corp.
|
|
*
|
|
* Test that an out-of-bounds branch to counter behaves as expected.
|
|
*/
|
|
|
|
#include <setjmp.h>
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <sys/mman.h>
|
|
#include <sys/types.h>
|
|
#include <sys/wait.h>
|
|
#include <ucontext.h>
|
|
#include <unistd.h>
|
|
|
|
#include "utils.h"
|
|
|
|
|
|
#define BAD_NIP 0x788c545a18000000ull
|
|
|
|
static struct pt_regs signal_regs;
|
|
static jmp_buf setjmp_env;
|
|
|
|
static void save_regs(ucontext_t *ctxt)
|
|
{
|
|
struct pt_regs *regs = ctxt->uc_mcontext.regs;
|
|
|
|
memcpy(&signal_regs, regs, sizeof(signal_regs));
|
|
}
|
|
|
|
static void segv_handler(int signum, siginfo_t *info, void *ctxt_v)
|
|
{
|
|
save_regs(ctxt_v);
|
|
longjmp(setjmp_env, 1);
|
|
}
|
|
|
|
static void usr2_handler(int signum, siginfo_t *info, void *ctxt_v)
|
|
{
|
|
save_regs(ctxt_v);
|
|
}
|
|
|
|
static int ok(void)
|
|
{
|
|
printf("Everything is OK in here.\n");
|
|
return 0;
|
|
}
|
|
|
|
#define REG_POISON 0x5a5a
|
|
#define POISONED_REG(n) ((((unsigned long)REG_POISON) << 48) | ((n) << 32) | \
|
|
(((unsigned long)REG_POISON) << 16) | (n))
|
|
|
|
static inline void poison_regs(void)
|
|
{
|
|
#define POISON_REG(n) \
|
|
"lis " __stringify(n) "," __stringify(REG_POISON) ";" \
|
|
"addi " __stringify(n) "," __stringify(n) "," __stringify(n) ";" \
|
|
"sldi " __stringify(n) "," __stringify(n) ", 32 ;" \
|
|
"oris " __stringify(n) "," __stringify(n) "," __stringify(REG_POISON) ";" \
|
|
"addi " __stringify(n) "," __stringify(n) "," __stringify(n) ";"
|
|
|
|
asm (POISON_REG(15)
|
|
POISON_REG(16)
|
|
POISON_REG(17)
|
|
POISON_REG(18)
|
|
POISON_REG(19)
|
|
POISON_REG(20)
|
|
POISON_REG(21)
|
|
POISON_REG(22)
|
|
POISON_REG(23)
|
|
POISON_REG(24)
|
|
POISON_REG(25)
|
|
POISON_REG(26)
|
|
POISON_REG(27)
|
|
POISON_REG(28)
|
|
POISON_REG(29)
|
|
: // inputs
|
|
: // outputs
|
|
: "15", "16", "17", "18", "19", "20", "21", "22", "23", "24", "25",
|
|
"26", "27", "28", "29"
|
|
);
|
|
#undef POISON_REG
|
|
}
|
|
|
|
static int check_regs(void)
|
|
{
|
|
unsigned long i;
|
|
|
|
for (i = 15; i <= 29; i++)
|
|
FAIL_IF(signal_regs.gpr[i] != POISONED_REG(i));
|
|
|
|
printf("Regs OK\n");
|
|
return 0;
|
|
}
|
|
|
|
static void dump_regs(void)
|
|
{
|
|
for (int i = 0; i < 32; i += 4) {
|
|
printf("r%02d 0x%016lx r%02d 0x%016lx " \
|
|
"r%02d 0x%016lx r%02d 0x%016lx\n",
|
|
i, signal_regs.gpr[i],
|
|
i+1, signal_regs.gpr[i+1],
|
|
i+2, signal_regs.gpr[i+2],
|
|
i+3, signal_regs.gpr[i+3]);
|
|
}
|
|
}
|
|
|
|
#ifdef _CALL_AIXDESC
|
|
struct opd {
|
|
unsigned long ip;
|
|
unsigned long toc;
|
|
unsigned long env;
|
|
};
|
|
static struct opd bad_opd = {
|
|
.ip = BAD_NIP,
|
|
};
|
|
#define BAD_FUNC (&bad_opd)
|
|
#else
|
|
#define BAD_FUNC BAD_NIP
|
|
#endif
|
|
|
|
int test_wild_bctr(void)
|
|
{
|
|
int (*func_ptr)(void);
|
|
struct sigaction segv = {
|
|
.sa_sigaction = segv_handler,
|
|
.sa_flags = SA_SIGINFO
|
|
};
|
|
struct sigaction usr2 = {
|
|
.sa_sigaction = usr2_handler,
|
|
.sa_flags = SA_SIGINFO
|
|
};
|
|
|
|
FAIL_IF(sigaction(SIGSEGV, &segv, NULL));
|
|
FAIL_IF(sigaction(SIGUSR2, &usr2, NULL));
|
|
|
|
bzero(&signal_regs, sizeof(signal_regs));
|
|
|
|
if (setjmp(setjmp_env) == 0) {
|
|
func_ptr = ok;
|
|
func_ptr();
|
|
|
|
kill(getpid(), SIGUSR2);
|
|
printf("Regs before:\n");
|
|
dump_regs();
|
|
bzero(&signal_regs, sizeof(signal_regs));
|
|
|
|
poison_regs();
|
|
|
|
func_ptr = (int (*)(void))BAD_FUNC;
|
|
func_ptr();
|
|
|
|
FAIL_IF(1); /* we didn't segv? */
|
|
}
|
|
|
|
FAIL_IF(signal_regs.nip != BAD_NIP);
|
|
|
|
printf("All good - took SEGV as expected branching to 0x%llx\n", BAD_NIP);
|
|
|
|
dump_regs();
|
|
FAIL_IF(check_regs());
|
|
|
|
return 0;
|
|
}
|
|
|
|
int main(void)
|
|
{
|
|
return test_harness(test_wild_bctr, "wild_bctr");
|
|
}
|