From 76eb84a4f4f101a11d6b8553ea71152d1c9ce731 Mon Sep 17 00:00:00 2001
From: Ryan Prichard <rprichard@google.com>
Date: Mon, 20 Apr 2020 18:01:00 -0700
Subject: [PATCH] __loader_cfi_fail: acquire g_dl_mutex

CfiFail calls find_containing_library, which searches the linker's
internal soinfo list, which could be modified by another thread.

Bug: http://b/150372650
Test: bionic-unit-tests
Change-Id: I59024a0a47913caa75702f15ec058b0a360727b5
(cherry picked from commit 172611f5cee5ce1351a83ec9f83e13235d04b008)
---
 linker/dlfcn.cpp | 1 +
 1 file changed, 1 insertion(+)

diff --git a/linker/dlfcn.cpp b/linker/dlfcn.cpp
index 255363f96..ec6850a40 100644
--- a/linker/dlfcn.cpp
+++ b/linker/dlfcn.cpp
@@ -284,6 +284,7 @@ android_namespace_t* __loader_android_get_exported_namespace(const char* name) {
 }
 
 void __loader_cfi_fail(uint64_t CallSiteTypeId, void* Ptr, void *DiagData, void *CallerPc) {
+  ScopedPthreadMutexLocker locker(&g_dl_mutex);
   CFIShadowWriter::CfiFail(CallSiteTypeId, Ptr, DiagData, CallerPc);
 }