tests/tcg/aarch64/bti-2.c

   1 /*
   2  * Branch target identification, basic notskip cases.
   3  */
   4
   5 #include <stdio.h>
   6 #include <signal.h>
   7 #include <string.h>
   8 #include <unistd.h>
   9 #include <sys/mman.h>
  10
  11 #ifndef PROT_BTI
  12 #define PROT_BTI  0x10
  13 #endif
  14
  15 static void skip2_sigill(int sig, siginfo_t *info, void *vuc)
  16 {
  17     ucontext_t *uc = vuc;
  18     uc->uc_mcontext.pc += 8;
  19     uc->uc_mcontext.pstate = 1;
  20 }
  21
  22 #define NOP       "nop"
  23 #define BTI_N     "hint #32"
  24 #define BTI_C     "hint #34"
  25 #define BTI_J     "hint #36"
  26 #define BTI_JC    "hint #38"
  27
  28 #define BTYPE_1(DEST)    \
  29     "mov x1, #1\n\t"     \
  30     "adr x16, 1f\n\t"    \
  31     "br x16\n"           \
  32 "1: " DEST "\n\t"        \
  33     "mov x1, #0"
  34
  35 #define BTYPE_2(DEST)    \
  36     "mov x1, #1\n\t"     \
  37     "adr x16, 1f\n\t"    \
  38     "blr x16\n"          \
  39 "1: " DEST "\n\t"        \
  40     "mov x1, #0"
  41
  42 #define BTYPE_3(DEST)    \
  43     "mov x1, #1\n\t"     \
  44     "adr x15, 1f\n\t"    \
  45     "br x15\n"           \
  46 "1: " DEST "\n\t"        \
  47     "mov x1, #0"
  48
  49 #define TEST(WHICH, DEST, EXPECT) \
  50     WHICH(DEST) "\n"              \
  51     ".if " #EXPECT "\n\t"         \
  52     "eor x1, x1," #EXPECT "\n"    \
  53     ".endif\n\t"                  \
  54     "add x0, x0, x1\n\t"
  55
  56 asm("\n"
  57 "test_begin:\n\t"
  58     BTI_C "\n\t"
  59     "mov x2, x30\n\t"
  60     "mov x0, #0\n\t"
  61
  62     TEST(BTYPE_1, NOP, 1)
  63     TEST(BTYPE_1, BTI_N, 1)
  64     TEST(BTYPE_1, BTI_C, 0)
  65     TEST(BTYPE_1, BTI_J, 0)
  66     TEST(BTYPE_1, BTI_JC, 0)
  67
  68     TEST(BTYPE_2, NOP, 1)
  69     TEST(BTYPE_2, BTI_N, 1)
  70     TEST(BTYPE_2, BTI_C, 0)
  71     TEST(BTYPE_2, BTI_J, 1)
  72     TEST(BTYPE_2, BTI_JC, 0)
  73
  74     TEST(BTYPE_3, NOP, 1)
  75     TEST(BTYPE_3, BTI_N, 1)
  76     TEST(BTYPE_3, BTI_C, 1)
  77     TEST(BTYPE_3, BTI_J, 0)
  78     TEST(BTYPE_3, BTI_JC, 0)
  79
  80     "ret x2\n"
  81 "test_end:"
  82 );
  83
  84 int main()
  85 {
  86     struct sigaction sa;
  87     void *tb, *te;
  88
  89     void *p = mmap(0, getpagesize(),
  90                    PROT_EXEC | PROT_READ | PROT_WRITE | PROT_BTI,
  91                    MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
  92     if (p == MAP_FAILED) {
  93         perror("mmap");
  94         return 1;
  95     }
  96
  97     memset(&sa, 0, sizeof(sa));
  98     sa.sa_sigaction = skip2_sigill;
  99     sa.sa_flags = SA_SIGINFO;
 100     if (sigaction(SIGILL, &sa, NULL) < 0) {
 101         perror("sigaction");
 102         return 1;
 103     }
 104
 105     /*
 106      * ??? With "extern char test_begin[]", some compiler versions
 107      * will use :got references, and some linker versions will
 108      * resolve this reference to a static symbol incorrectly.
 109      * Bypass this error by using a pc-relative reference directly.
 110      */
 111     asm("adr %0, test_begin; adr %1, test_end" : "=r"(tb), "=r"(te));
 112
 113     memcpy(p, tb, te - tb);
 114
 115     return ((int (*)(void))p)();
 116 }