[compiler-rt] 0ebb756 - [hwasan] Add __hwasan_init constructor to runtime lib.

[Mitch Phillips via llvm-commits]

Author: Mitch Phillips
Date: 2021-08-04T11:18:23-07:00
New Revision: 0ebb75608759cc1ee1016699e15d03e8e3f30d14

URL: https://github.com/llvm/llvm-project/commit/0ebb75608759cc1ee1016699e15d03e8e3f30d14
DIFF: https://github.com/llvm/llvm-project/commit/0ebb75608759cc1ee1016699e15d03e8e3f30d14.diff

LOG: [hwasan] Add __hwasan_init constructor to runtime lib.

Found by an Android toolchain upgrade, inherited module constructors
(like init_have_lse_atomics from the builtins) can sneak into the hwasan
runtime. If these inherited constructors call hwasanified libc
functions, then the HWASan runtime isn't setup enough, and the code
crashes.

Mark the initialized as a high-priority initializer to fix this.

Reviewed By: pcc, yabinc

Differential Revision: https://reviews.llvm.org/D107391

Added: 
    

Modified: 
    compiler-rt/lib/hwasan/hwasan.cpp

Removed: 
    


################################################################################
diff  --git a/compiler-rt/lib/hwasan/hwasan.cpp b/compiler-rt/lib/hwasan/hwasan.cpp
index cbe0dee66dcda..e687f56b63f59 100644
--- a/compiler-rt/lib/hwasan/hwasan.cpp
+++ b/compiler-rt/lib/hwasan/hwasan.cpp
@@ -319,7 +319,7 @@ void __hwasan_init_static() {
     InitializeSingleGlobal(global);
 }
 
-void __hwasan_init() {
+__attribute__((constructor(0))) void __hwasan_init() {
   CHECK(!hwasan_init_is_running);
   if (hwasan_inited) return;
   hwasan_init_is_running = 1;