contrib/compiler-rt/lib/ubsan_minimal/ubsan_minimal_handlers.cc

   1 #include "sanitizer_common/sanitizer_atomic.h"
   2
   3 #include <stdlib.h>
   4 #include <stdint.h>
   5 #include <string.h>
   6 #include <unistd.h>
   7
   8 #ifdef KERNEL_USE
   9 extern "C" void ubsan_message(const char *msg);
  10 static void message(const char *msg) { ubsan_message(msg); }
  11 #else
  12 static void message(const char *msg) {
  13   write(2, msg, strlen(msg));
  14 }
  15 #endif
  16
  17 static const int kMaxCallerPcs = 20;
  18 static __sanitizer::atomic_uintptr_t caller_pcs[kMaxCallerPcs];
  19 // Number of elements in caller_pcs. A special value of kMaxCallerPcs + 1 means
  20 // that "too many errors" has already been reported.
  21 static __sanitizer::atomic_uint32_t caller_pcs_sz;
  22
  23 __attribute__((noinline)) static bool report_this_error(void *caller_p) {
  24   uintptr_t caller = reinterpret_cast<uintptr_t>(caller_p);
  25   if (caller == 0) return false;
  26   while (true) {
  27     unsigned sz = __sanitizer::atomic_load_relaxed(&caller_pcs_sz);
  28     if (sz > kMaxCallerPcs) return false;  // early exit
  29     // when sz==kMaxCallerPcs print "too many errors", but only when cmpxchg
  30     // succeeds in order to not print it multiple times.
  31     if (sz > 0 && sz < kMaxCallerPcs) {
  32       uintptr_t p;
  33       for (unsigned i = 0; i < sz; ++i) {
  34         p = __sanitizer::atomic_load_relaxed(&caller_pcs[i]);
  35         if (p == 0) break;  // Concurrent update.
  36         if (p == caller) return false;
  37       }
  38       if (p == 0) continue;  // FIXME: yield?
  39     }
  40
  41     if (!__sanitizer::atomic_compare_exchange_strong(
  42             &caller_pcs_sz, &sz, sz + 1, __sanitizer::memory_order_seq_cst))
  43       continue;  // Concurrent update! Try again from the start.
  44
  45     if (sz == kMaxCallerPcs) {
  46       message("ubsan: too many errors\n");
  47       return false;
  48     }
  49     __sanitizer::atomic_store_relaxed(&caller_pcs[sz], caller);
  50     return true;
  51   }
  52 }
  53
  54 #if defined(__ANDROID__)
  55 extern "C" __attribute__((weak)) void android_set_abort_message(const char *);
  56 static void abort_with_message(const char *msg) {
  57   if (&android_set_abort_message) android_set_abort_message(msg);
  58   abort();
  59 }
  60 #else
  61 static void abort_with_message(const char *) { abort(); }
  62 #endif
  63
  64 #if SANITIZER_DEBUG
  65 namespace __sanitizer {
  66 // The DCHECK macro needs this symbol to be defined.
  67 void NORETURN CheckFailed(const char *file, int, const char *cond, u64, u64) {
  68   message("Sanitizer CHECK failed: ");
  69   message(file);
  70   message(":?? : "); // FIXME: Show line number.
  71   message(cond);
  72   abort();
  73 }
  74 } // namespace __sanitizer
  75 #endif
  76
  77 #define INTERFACE extern "C" __attribute__((visibility("default")))
  78
  79 // FIXME: add caller pc to the error message (possibly as "ubsan: error-type
  80 // @1234ABCD").
  81 #define HANDLER_RECOVER(name, msg)                               \
  82   INTERFACE void __ubsan_handle_##name##_minimal() {             \
  83     if (!report_this_error(__builtin_return_address(0))) return; \
  84     message("ubsan: " msg "\n");                                 \
  85   }
  86
  87 #define HANDLER_NORECOVER(name, msg)                             \
  88   INTERFACE void __ubsan_handle_##name##_minimal_abort() {       \
  89     message("ubsan: " msg "\n");                                 \
  90     abort_with_message("ubsan: " msg);                           \
  91   }
  92
  93 #define HANDLER(name, msg)                                       \
  94   HANDLER_RECOVER(name, msg)                                     \
  95   HANDLER_NORECOVER(name, msg)
  96
  97 HANDLER(type_mismatch, "type-mismatch")
  98 HANDLER(alignment_assumption, "alignment-assumption")
  99 HANDLER(add_overflow, "add-overflow")
 100 HANDLER(sub_overflow, "sub-overflow")
 101 HANDLER(mul_overflow, "mul-overflow")
 102 HANDLER(negate_overflow, "negate-overflow")
 103 HANDLER(divrem_overflow, "divrem-overflow")
 104 HANDLER(shift_out_of_bounds, "shift-out-of-bounds")
 105 HANDLER(out_of_bounds, "out-of-bounds")
 106 HANDLER_RECOVER(builtin_unreachable, "builtin-unreachable")
 107 HANDLER_RECOVER(missing_return, "missing-return")
 108 HANDLER(vla_bound_not_positive, "vla-bound-not-positive")
 109 HANDLER(float_cast_overflow, "float-cast-overflow")
 110 HANDLER(load_invalid_value, "load-invalid-value")
 111 HANDLER(invalid_builtin, "invalid-builtin")
 112 HANDLER(function_type_mismatch, "function-type-mismatch")
 113 HANDLER(implicit_conversion, "implicit-conversion")
 114 HANDLER(nonnull_arg, "nonnull-arg")
 115 HANDLER(nonnull_return, "nonnull-return")
 116 HANDLER(nullability_arg, "nullability-arg")
 117 HANDLER(nullability_return, "nullability-return")
 118 HANDLER(pointer_overflow, "pointer-overflow")
 119 HANDLER(cfi_check_fail, "cfi-check-fail")