llvm/compiler-rt/test/hwasan/TestCases/stack-history-length.c

// RUN: %clang_hwasan -O1 %s -o %t
// RUN: %env_hwasan_opts=stack_history_size=2048 not %run %t 2045 2>&1 | FileCheck %s --check-prefix=YES
// RUN: %env_hwasan_opts=stack_history_size=2048 not %run %t 2047 2>&1 | FileCheck %s --check-prefix=NO

// Run the same tests as above, but using the __hwasan_add_frame_record libcall.
// The output should be the exact same.
// RUN: %clang_hwasan -O1 %s -o %t -mllvm -hwasan-record-stack-history=libcall
// RUN: %env_hwasan_opts=stack_history_size=2048 not %run %t 2045 2>&1 | FileCheck %s --check-prefix=YES
// RUN: %env_hwasan_opts=stack_history_size=2048 not %run %t 2047 2>&1 | FileCheck %s --check-prefix=NO

// Stack histories are currently not recorded on x86.
// XFAIL: target=x86_64{{.*}}

#include <assert.h>
#include <sanitizer/hwasan_interface.h>
#include <stdlib.h>

void USE(void *x) { // pretend_to_do_something(void *x)
  __asm__ __volatile__("" : : "r" (x) : "memory");
}

volatile int four = 4;
__attribute__((noinline)) void FUNC0() { int x[4]; USE(&x[0]); }
__attribute__((noinline)) void FUNC() { int x[4]; USE(&x[0]); }
__attribute__((noinline)) void OOB() {
  int x[4];
  int y[4];
  // With -hwasan-generate-tags-with-calls=false, stack tags can occasionally
  // be zero, leading to a false negative
  // (https://github.com/llvm/llvm-project/issues/69221). Work around it by
  // using the neighboring variable, which is guaranteed by
  // -hwasan-generate-tags-with-calls=false to have a different (hence
  // non-zero) tag.
  if (__hwasan_tag_pointer(x, 0) == x) {
    assert(__hwasan_tag_pointer(y, 0) != y);
    y[four] = 0;
  } else {
    x[four] = 0;
  }
  USE(&x[0]);
  USE(&y[0]);
}

int main(int argc, char **argv) {
  int X = argc == 2 ? atoi(argv[1]) : 10;
  // FUNC0 is X+2's element of the ring buffer.
  // If runtime buffer size is less than it, FUNC0 record will be lost.
  FUNC0();
  for (int i = 0; i < X; ++i)
    FUNC();
  // Make at least one call to OOB where base tag != 0 so that the bug is caught
  // at least once.
  OOB();
  OOB();
}

// YES: Previously allocated frames
// YES: OOB
// YES: FUNC
// YES: FUNC0

// NO: Previously allocated frames
// NO: OOB
// NO: FUNC
// NO-NOT: FUNC0