[hwasan] make error reporting look more like in asan, print the memory tag around the buggy access, simplify one test

llvm-svn: 340470

3 files changed, 50 insertions, 28 deletions

diff --git a/compiler-rt/lib/hwasan/hwasan_report.cc b/compiler-rt/lib/hwasan/hwasan_report.cc
index 16e9016ea35..c390c0c50d7 100644
--- a/compiler-rt/lib/hwasan/hwasan_report.cc
+++ b/compiler-rt/lib/hwasan/hwasan_report.cc
@@ -37,6 +37,7 @@ static StackTrace GetStackTraceFromId(u32 id) {
 class Decorator: public __sanitizer::SanitizerCommonDecorator {
  public:
   Decorator() : SanitizerCommonDecorator() { }
+  const char *Access() { return Blue(); }
   const char *Allocation() const { return Magenta(); }
   const char *Origin() const { return Magenta(); }
   const char *Name() const { return Green(); }
@@ -113,21 +114,46 @@ void ReportTagMismatch(StackTrace *stack, uptr addr, uptr access_size,
   ScopedErrorReportLock l;
 
   Decorator d;
-  Printf("%s", d.Warning());
+  Printf("%s", d.Error());
   uptr address = GetAddressFromPointer(addr);
-  Printf("%s of size %zu at %p\n", is_store ? "WRITE" : "READ", access_size,
-         address);
+  // TODO: when possible, try to print heap-use-after-free, etc.
+  const char *bug_type = "tag-mismatch";
+  uptr pc = stack->size ? stack->trace[0] : 0;
+  Report("ERROR: %s: %s on address %p at pc %p\n", SanitizerToolName, bug_type, address, pc);
 
   tag_t ptr_tag = GetTagFromPointer(addr);
-  tag_t mem_tag = *(tag_t *)MEM_TO_SHADOW(address);
-  Printf("pointer tag 0x%x\nmemory tag  0x%x\n", ptr_tag, mem_tag);
+  tag_t *tag_ptr = reinterpret_cast<tag_t*>(MEM_TO_SHADOW(address));
+  tag_t mem_tag = *tag_ptr;
+  Printf("%s", d.Access());
+  Printf("%s of size %zu at %p tags: %02x/%02x (ptr/mem)\n",
+         is_store ? "WRITE" : "READ", access_size, address, ptr_tag, mem_tag);
   Printf("%s", d.Default());
 
   stack->Print();
 
   PrintAddressDescription(address, access_size);
 
-  ReportErrorSummary("tag-mismatch", stack);
+  Printf(
+      "Memory tags around the buggy address (one tag corresponds to %zd "
+      "bytes):\n", kShadowAlignment);
+
+  const uptr row_len = 16;  // better be power of two.
+  const uptr num_rows = 11;
+  tag_t *center_row_beg = reinterpret_cast<tag_t *>(
+      RoundDownTo(reinterpret_cast<uptr>(tag_ptr), row_len));
+  tag_t *beg_row = center_row_beg - row_len * (num_rows / 2);
+  tag_t *end_row = center_row_beg + row_len * (num_rows / 2);
+  for (tag_t *row = beg_row; row < end_row; row += row_len) {
+    Printf("%s", row == center_row_beg ? "=>" : "  ");
+    for (uptr i = 0; i < row_len; i++) {
+      Printf("%s", row + i == tag_ptr ? "[" : " ");
+      Printf("%02x", row[i]);
+      Printf("%s", row + i == tag_ptr ? "]" : " ");
+    }
+    Printf("%s\n", row == center_row_beg ? "<=" : "  ");
+  }
+
+  ReportErrorSummary(bug_type, stack);
 }
 
 }  // namespace __hwasan
diff --git a/compiler-rt/test/hwasan/TestCases/longjmp.c b/compiler-rt/test/hwasan/TestCases/longjmp.c
index e78488afb02..8d847b54b27 100644
--- a/compiler-rt/test/hwasan/TestCases/longjmp.c
+++ b/compiler-rt/test/hwasan/TestCases/longjmp.c
@@ -22,7 +22,5 @@ int f(void *caller_frame) {
 
 int main() {
   return f(__builtin_frame_address(0));
-  // CHECK: READ of size 8
-  // CHECK: pointer tag
-  // CHECK: memory tag 0x0
+  // CHECK: READ of size 8 at {{.*}} tags: {{.*}}/00 (ptr/mem)
 }
diff --git a/compiler-rt/test/hwasan/TestCases/use-after-free.c b/compiler-rt/test/hwasan/TestCases/use-after-free.c
index b9f6060112c..46739051ab4 100644
--- a/compiler-rt/test/hwasan/TestCases/use-after-free.c
+++ b/compiler-rt/test/hwasan/TestCases/use-after-free.c
@@ -1,13 +1,14 @@
-// RUN: %clang_hwasan -O0 -DLOAD %s -o %t && not %run %t 2>&1 | FileCheck %s --check-prefixes=CHECK,LOAD
-// RUN: %clang_hwasan -O1 -DLOAD %s -o %t && not %run %t 2>&1 | FileCheck %s --check-prefixes=CHECK,LOAD
-// RUN: %clang_hwasan -O2 -DLOAD %s -o %t && not %run %t 2>&1 | FileCheck %s --check-prefixes=CHECK,LOAD
-// RUN: %clang_hwasan -O3 -DLOAD %s -o %t && not %run %t 2>&1 | FileCheck %s --check-prefixes=CHECK,LOAD
+// RUN: %clang_hwasan -O0 -DISREAD=1 %s -o %t && not %run %t 2>&1 | FileCheck %s --check-prefixes=CHECK
+// RUN: %clang_hwasan -O1 -DISREAD=1 %s -o %t && not %run %t 2>&1 | FileCheck %s --check-prefixes=CHECK
+// RUN: %clang_hwasan -O2 -DISREAD=1 %s -o %t && not %run %t 2>&1 | FileCheck %s --check-prefixes=CHECK
+// RUN: %clang_hwasan -O3 -DISREAD=1 %s -o %t && not %run %t 2>&1 | FileCheck %s --check-prefixes=CHECK
 
-// RUN: %clang_hwasan -O0 -DSTORE %s -o %t && not %run %t 2>&1 | FileCheck %s --check-prefixes=CHECK,STORE
+// RUN: %clang_hwasan -O0 -DISREAD=0 %s -o %t && not %run %t 2>&1 | FileCheck %s --check-prefixes=CHECK
 
 // REQUIRES: stable-runtime
 
 #include <stdlib.h>
+#include <stdio.h>
 #include <sanitizer/hwasan_interface.h>
 
 int main() {
@@ -15,25 +16,22 @@ int main() {
   char * volatile x = (char*)malloc(10);
   free(x);
   __hwasan_disable_allocator_tagging();
-#ifdef STORE
-  x[5] = 42;
-#endif
-#ifdef LOAD
-  return x[5];
-#endif
-  // LOAD: READ of size 1 at
-  // LOAD: #0 {{.*}} in main {{.*}}use-after-free.c:22
-
-  // STORE: WRITE of size 1 at
-  // STORE: #0 {{.*}} in main {{.*}}use-after-free.c:19
+  fprintf(stderr, "Going to do a %s\n", ISREAD ? "READ" : "WRITE");
+  // CHECK: Going to do a [[TYPE:[A-Z]*]]
+  int r = 0;
+  if (ISREAD) r = x[5]; else x[5] = 42;  // should be on the same line.
+  // CHECK: [[TYPE]] of size 1 at {{.*}} tags: [[PTR_TAG:[0-9a-f][0-9a-f]]]/[[MEM_TAG:[0-9a-f][0-9a-f]]] (ptr/mem)
+  // CHECK: #0 {{.*}} in main {{.*}}use-after-free.c:[[@LINE-2]]
 
   // CHECK: freed here:
   // CHECK: #0 {{.*}} in {{.*}}free{{.*}} {{.*}}hwasan_interceptors.cc
-  // CHECK: #1 {{.*}} in main {{.*}}use-after-free.c:16
+  // CHECK: #1 {{.*}} in main {{.*}}use-after-free.c:[[@LINE-11]]
 
   // CHECK: previously allocated here:
   // CHECK: #0 {{.*}} in {{.*}}malloc{{.*}} {{.*}}hwasan_interceptors.cc
-  // CHECK: #1 {{.*}} in main {{.*}}use-after-free.c:15
-
+  // CHECK: #1 {{.*}} in main {{.*}}use-after-free.c:[[@LINE-16]]
+  // CHECK: Memory tags around the buggy address (one tag corresponds to 16 bytes):
+  // CHECK: =>{{.*}}[[MEM_TAG]]
   // CHECK: SUMMARY: HWAddressSanitizer: tag-mismatch {{.*}} in main
+  return r;
 }