[malloc dispatch] Install dispatch over the top of GWP-ASan.
When enabled, GWP-ASan sets the current dispatch table. Then, when a
shim layer (malloc_debug, malloc_hooks, heapprofd) comes along, they
should (by design) overwrite the current dispatch table.
Currently, these shim layers check to see whether malloc_limit is
installed by checking the current dispatch table against nullptr.
Because GWP-ASan owns the current dispatch table, the shim thinks that
malloc_limit is installed and falls back to only use the default
dispatch, thinking that malloc_limit will call them. This is not the
case, and they should take over the current dispatch pointer.
Bug: 135634846
Test: atest bionic
Change-Id: Ifb6f8864a15af9ac7f20d9364c40f73c5dd9d870
diff --git a/libc/bionic/malloc_common_dynamic.cpp b/libc/bionic/malloc_common_dynamic.cpp
index 79d2521..02dc331 100644
--- a/libc/bionic/malloc_common_dynamic.cpp
+++ b/libc/bionic/malloc_common_dynamic.cpp
@@ -344,7 +344,7 @@
// Do a pointer swap so that all of the functions become valid at once to
// avoid any initialization order problems.
atomic_store(&globals->default_dispatch_table, &globals->malloc_dispatch_table);
- if (GetDispatchTable() == nullptr) {
+ if (!MallocLimitInstalled()) {
atomic_store(&globals->current_dispatch_table, &globals->malloc_dispatch_table);
}