From db492b3ca753c4ef688d0daf648294de0c89145e Mon Sep 17 00:00:00 2001
From: Elliott Hughes <enh@google.com>
Date: Thu, 3 Jan 2013 15:44:03 -0800
Subject: [PATCH] Fix debug malloc.
...which has been broken since the linker data structures went read-only.
Bug: 7941716
Change-Id: If28f6bac0fcb13e371e4d85b064544f561c8d692
---
libc/bionic/malloc_debug_common.cpp | 18 ++++++++----------
linker/linker.cpp | 12 ++++++------
2 files changed, 14 insertions(+), 16 deletions(-)
diff --git a/libc/bionic/malloc_debug_common.cpp b/libc/bionic/malloc_debug_common.cpp
index 0594c0aa8..624a40e26 100644
--- a/libc/bionic/malloc_debug_common.cpp
+++ b/libc/bionic/malloc_debug_common.cpp
@@ -242,7 +242,7 @@ extern "C" void* memalign(size_t alignment, size_t bytes) {
return __libc_malloc_dispatch->memalign(alignment, bytes);
}
-/* We implement malloc debugging only in libc.so, so code bellow
+/* We implement malloc debugging only in libc.so, so code below
* must be excluded if we compile this file for static libc.a
*/
#ifndef LIBC_STATIC
@@ -280,13 +280,10 @@ extern char* __progname;
*/
static void* libc_malloc_impl_handle = NULL;
-/* Make sure we have MALLOC_ALIGNMENT that matches the one that is
- * used in dlmalloc. Emulator's memchecker needs this value to properly
- * align its guarding zones.
- */
+// This must match the alignment used by dlmalloc.
#ifndef MALLOC_ALIGNMENT
-#define MALLOC_ALIGNMENT ((size_t)8U)
-#endif /* MALLOC_ALIGNMENT */
+#define MALLOC_ALIGNMENT ((size_t)(2 * sizeof(void *)))
+#endif
/* This variable is set to the value of property libc.debug.malloc.backlog,
* when the value of libc.debug.malloc = 10. It determines the size of the
@@ -449,6 +446,7 @@ static void malloc_init_impl() {
dlclose(libc_malloc_impl_handle);
return;
}
+
if (memcheck_initialize(MALLOC_ALIGNMENT, memcheck_tracing)) {
dlclose(libc_malloc_impl_handle);
return;
@@ -513,17 +511,17 @@ extern "C" void malloc_debug_init() {
/* We need to initialize malloc iff we implement here custom
* malloc routines (i.e. USE_DL_PREFIX is defined) for libc.so */
#if defined(USE_DL_PREFIX) && !defined(LIBC_STATIC)
- if (pthread_once(&malloc_init_once_ctl, malloc_init_impl)) {
+ if (pthread_once(&malloc_init_once_ctl, malloc_init_impl)) {
error_log("Unable to initialize malloc_debug component.");
}
#endif // USE_DL_PREFIX && !LIBC_STATIC
}
extern "C" void malloc_debug_fini() {
- /* We need to finalize malloc iff we implement here custom
+ /* We need to finalize malloc iff we implement here custom
* malloc routines (i.e. USE_DL_PREFIX is defined) for libc.so */
#if defined(USE_DL_PREFIX) && !defined(LIBC_STATIC)
- if (pthread_once(&malloc_fini_once_ctl, malloc_fini_impl)) {
+ if (pthread_once(&malloc_fini_once_ctl, malloc_fini_impl)) {
error_log("Unable to finalize malloc_debug component.");
}
#endif // USE_DL_PREFIX && !LIBC_STATIC
diff --git a/linker/linker.cpp b/linker/linker.cpp
index 6a2a958ec..09f479fbb 100755
--- a/linker/linker.cpp
+++ b/linker/linker.cpp
@@ -1366,24 +1366,24 @@ void soinfo::CallArray(const char* array_name UNUSED, unsigned* array, int count
TRACE("[ Looking at %s[%d] *%p == 0x%08x ]\n", array_name, n, array, *array);
void (*func)() = (void (*)()) *array;
array += step;
- if (((int) func == 0) || ((int) func == -1)) {
- continue;
- }
- TRACE("[ Calling func @ %p ]\n", func);
- func();
+ CallFunction("function", func);
}
TRACE("[ Done calling %s for '%s' ]\n", array_name, name);
}
void soinfo::CallFunction(const char* function_name UNUSED, void (*function)()) {
- if (function == NULL) {
+ if (function == NULL || reinterpret_cast<uintptr_t>(function) == static_cast<uintptr_t>(-1)) {
return;
}
TRACE("[ Calling %s @ %p for '%s' ]\n", function_name, function, name);
function();
TRACE("[ Done calling %s for '%s' ]\n", function_name, name);
+
+ // The function may have called dlopen(3) or dlclose(3), so we need to ensure our data structures
+ // are still writable. This happens with our debug malloc (see http://b/7941716).
+ set_soinfo_pool_protection(PROT_READ | PROT_WRITE);
}
void soinfo::CallPreInitConstructors() {