Reland^2 "[MTE] remap stacks with PROT_MTE when requested by dlopened library"
Also enable stack MTE if main binary links in a library that needs it.
Otherwise the following is possible:
1. a binary doesn't require stack MTE, but links in libraries that use
stg on the stack
2. that binary later dlopens a library that requires stack MTE, and our
logic in dlopen remaps the stacks with MTE
3. the libraries from step 1 now have tagged pointers with missing tags
in memory, so things go wrong
This reverts commit f53e91cc810be2a36377f3b7765f50c89f1f0046.
Reason for revert: Fixed problem detected in b/324568991
Test: atest memtag_stack_dlopen_test with MTE enabled
Test: check crash is gone on fullmte build
Change-Id: I4a93f6814a19683c3ea5fe1e6d455df5459d31e1
diff --git a/libc/private/bionic_globals.h b/libc/private/bionic_globals.h
index 23f2953..6f1e389 100644
--- a/libc/private/bionic_globals.h
+++ b/libc/private/bionic_globals.h
@@ -50,6 +50,7 @@
uintptr_t heap_pointer_tag;
_Atomic(bool) memtag_stack;
_Atomic(bool) decay_time_enabled;
+ _Atomic(bool) memtag;
// In order to allow a complete switch between dispatch tables without
// the need for copying each function by function in the structure,
@@ -137,6 +138,7 @@
bool initial_memtag_stack = false;
int64_t heap_tagging_upgrade_timer_sec = 0;
+ void (*memtag_stack_dlopen_callback)() = nullptr;
pthread_mutex_t crash_detail_page_lock = PTHREAD_MUTEX_INITIALIZER;
crash_detail_page_t* crash_detail_page = nullptr;
};