1 files changed, 103 insertions, 0 deletions
diff --git a/pcr/llvm38/msan-prevent-initialization-failure-with-newer-glibc.patch b/pcr/llvm38/msan-prevent-initialization-failure-with-newer-glibc.patch
new file mode 100644
index 000000000..57387a6a1
--- /dev/null
+++ b/pcr/llvm38/msan-prevent-initialization-failure-with-newer-glibc.patch
@@ -0,0 +1,103 @@
+Index: lib/msan/msan_interceptors.cc
+===================================================================
+--- lib/msan/msan_interceptors.cc	(revision 282231)
++++ lib/msan/msan_interceptors.cc	(revision 282232)
+@@ -64,6 +64,23 @@
+   return in_interceptor_scope;
+ }
+ 
++static uptr allocated_for_dlsym;
++static const uptr kDlsymAllocPoolSize = 1024;
++static uptr alloc_memory_for_dlsym[kDlsymAllocPoolSize];
++
++static bool IsInDlsymAllocPool(const void *ptr) {
++  uptr off = (uptr)ptr - (uptr)alloc_memory_for_dlsym;
++  return off < sizeof(alloc_memory_for_dlsym);
++}
++
++static void *AllocateFromLocalPool(uptr size_in_bytes) {
++  uptr size_in_words = RoundUpTo(size_in_bytes, kWordSize) / kWordSize;
++  void *mem = (void *)&alloc_memory_for_dlsym[allocated_for_dlsym];
++  allocated_for_dlsym += size_in_words;
++  CHECK_LT(allocated_for_dlsym, kDlsymAllocPoolSize);
++  return mem;
++}
++
+ #define ENSURE_MSAN_INITED() do { \
+   CHECK(!msan_init_is_running); \
+   if (!msan_inited) { \
+@@ -227,7 +244,7 @@
+ 
+ INTERCEPTOR(void, free, void *ptr) {
+   GET_MALLOC_STACK_TRACE;
+-  if (!ptr) return;
++  if (!ptr || UNLIKELY(IsInDlsymAllocPool(ptr))) return;
+   MsanDeallocate(&stack, ptr);
+ }
+ 
+@@ -234,7 +251,7 @@
+ #if !SANITIZER_FREEBSD
+ INTERCEPTOR(void, cfree, void *ptr) {
+   GET_MALLOC_STACK_TRACE;
+-  if (!ptr) return;
++  if (!ptr || UNLIKELY(IsInDlsymAllocPool(ptr))) return;
+   MsanDeallocate(&stack, ptr);
+ }
+ #define MSAN_MAYBE_INTERCEPT_CFREE INTERCEPT_FUNCTION(cfree)
+@@ -907,27 +924,29 @@
+ 
+ INTERCEPTOR(void *, calloc, SIZE_T nmemb, SIZE_T size) {
+   GET_MALLOC_STACK_TRACE;
+-  if (UNLIKELY(!msan_inited)) {
++  if (UNLIKELY(!msan_inited))
+     // Hack: dlsym calls calloc before REAL(calloc) is retrieved from dlsym.
+-    const SIZE_T kCallocPoolSize = 1024;
+-    static uptr calloc_memory_for_dlsym[kCallocPoolSize];
+-    static SIZE_T allocated;
+-    SIZE_T size_in_words = ((nmemb * size) + kWordSize - 1) / kWordSize;
+-    void *mem = (void*)&calloc_memory_for_dlsym[allocated];
+-    allocated += size_in_words;
+-    CHECK(allocated < kCallocPoolSize);
+-    return mem;
+-  }
++    return AllocateFromLocalPool(nmemb * size);
+   return MsanCalloc(&stack, nmemb, size);
+ }
+ 
+ INTERCEPTOR(void *, realloc, void *ptr, SIZE_T size) {
+   GET_MALLOC_STACK_TRACE;
++  if (UNLIKELY(IsInDlsymAllocPool(ptr))) {
++    uptr offset = (uptr)ptr - (uptr)alloc_memory_for_dlsym;
++    uptr copy_size = Min(size, kDlsymAllocPoolSize - offset);
++    void *new_ptr = AllocateFromLocalPool(size);
++    internal_memcpy(new_ptr, ptr, copy_size);
++    return new_ptr;
++  }
+   return MsanReallocate(&stack, ptr, size, sizeof(u64), false);
+ }
+ 
+ INTERCEPTOR(void *, malloc, SIZE_T size) {
+   GET_MALLOC_STACK_TRACE;
++  if (UNLIKELY(!msan_inited))
++    // Hack: dlsym calls malloc before REAL(malloc) is retrieved from dlsym.
++    return AllocateFromLocalPool(size);
+   return MsanReallocate(&stack, nullptr, size, sizeof(u64), false);
+ }
+ 
+Index: lib/asan/asan_malloc_linux.cc
+===================================================================
+--- lib/asan/asan_malloc_linux.cc	(revision 282231)
++++ lib/asan/asan_malloc_linux.cc	(revision 282232)
+@@ -78,7 +78,11 @@
+   if (UNLIKELY(IsInDlsymAllocPool(ptr))) {
+     uptr offset = (uptr)ptr - (uptr)alloc_memory_for_dlsym;
+     uptr copy_size = Min(size, kDlsymAllocPoolSize - offset);
+-    void *new_ptr = asan_malloc(size, &stack);
++    void *new_ptr;
++    if (UNLIKELY(!asan_inited))
++      new_ptr = AllocateFromLocalPool(size);
++    else
++      new_ptr = asan_malloc(size, &stack);
+     internal_memcpy(new_ptr, ptr, copy_size);
+     return new_ptr;
+   }