commit 73750dc38ec4be640c7a4569374358bb7725a39c
author Florian Mayer <fmayer@google.com> Fri Mar 08 14:10:48 2024 -0800
committer Florian Mayer <fmayer@google.com> Tue Mar 12 12:42:23 2024 -0700
tree 657ac445e09629438bde2e149dbdb2ab4cb477cf
parent 5cc10a9a0d594203f9692799bfcd55005b38a0bd

Move memtag_stack out of libc_globals

We cannot use a WriteProtected because we are accessing it in a
multithreaded context.

Test: atest memtag_stack_dlopen_test w/ MTE
Test: atest bionic-unit-tests w/ MTE
Test: atest bionic-unit-tests on _fullmte
Bug: 328256432
Change-Id: I39faa75f97fd5b3fb755a46e88346c17c0e9a8e2

libc/bionic/pthread_create.cpp

diff --git a/libc/bionic/pthread_create.cpp b/libc/bionic/pthread_create.cpp
index 194db18..5bd4f16 100644
--- a/libc/bionic/pthread_create.cpp
+++ b/libc/bionic/pthread_create.cpp
@@ -91,7 +91,7 @@
   // Create and set an alternate signal stack.
   int prot = PROT_READ | PROT_WRITE;
 #ifdef __aarch64__
-  if (atomic_load(&__libc_globals->memtag_stack)) {
+  if (atomic_load(&__libc_memtag_stack)) {
     prot |= PROT_MTE;
   }
 #endif
@@ -237,7 +237,7 @@
   int prot = PROT_READ | PROT_WRITE;
   const char* prot_str = "R+W";
 #ifdef __aarch64__
-  if (atomic_load(&__libc_globals->memtag_stack)) {
+  if (atomic_load(&__libc_memtag_stack)) {
     prot |= PROT_MTE;
     prot_str = "R+W+MTE";
   }