Move the ILP32 mremap() hackery into legacy_32_bit_support.cpp.
Similar to mmap(), this confuses me every time I look at it. Move it out
of the way, and make it clearer that this is just junk that can be
deleted when we remove 32-bit support.
Also improve coverage by adding a test for the varargs special case.
Ignore-AOSP-First: work around the lack of an ABI 35 dump in AOSP
Test: treehugger
Change-Id: Ia375c29d18e31e646b795e643534f0be07d382b9
diff --git a/libc/bionic/legacy_32_bit_support.cpp b/libc/bionic/legacy_32_bit_support.cpp
index 314fe9b..4e19ebf 100644
--- a/libc/bionic/legacy_32_bit_support.cpp
+++ b/libc/bionic/legacy_32_bit_support.cpp
@@ -30,6 +30,7 @@
#include <errno.h>
#include <fcntl.h>
+#include <stdarg.h>
#include <stdint.h>
#include <sys/mman.h>
#include <sys/resource.h>
@@ -135,3 +136,28 @@
void* mmap(void* addr, size_t size, int prot, int flags, int fd, off_t offset) {
return mmap64(addr, size, prot, flags, fd, static_cast<off64_t>(offset));
}
+
+// The only difference here is that the libc API uses varargs for the
+// optional `new_address` argument that's only used by MREMAP_FIXED.
+extern "C" void* __mremap(void*, size_t, size_t, int, void*);
+
+void* mremap(void* old_address, size_t old_size, size_t new_size, int flags, ...) {
+ // Prevent allocations large enough for `end - start` to overflow,
+ // to avoid security bugs.
+ size_t rounded = __BIONIC_ALIGN(new_size, page_size());
+ if (rounded < new_size || rounded > PTRDIFF_MAX) {
+ errno = ENOMEM;
+ return MAP_FAILED;
+ }
+
+ // The optional argument is only valid if the MREMAP_FIXED flag is set,
+ // so we assume it's not present otherwise.
+ void* new_address = nullptr;
+ if ((flags & MREMAP_FIXED) != 0) {
+ va_list ap;
+ va_start(ap, flags);
+ new_address = va_arg(ap, void*);
+ va_end(ap);
+ }
+ return __mremap(old_address, old_size, new_size, flags, new_address);
+}
diff --git a/libc/bionic/mremap.cpp b/libc/bionic/mremap.cpp
deleted file mode 100644
index 88ec829..0000000
--- a/libc/bionic/mremap.cpp
+++ /dev/null
@@ -1,58 +0,0 @@
-/*
- * Copyright (C) 2015 The Android Open Source Project
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- * * Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in
- * the documentation and/or other materials provided with the
- * distribution.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
- * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
- * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
- * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
- * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
- * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
- * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
- * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
- * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- */
-
-#include <errno.h>
-#include <sys/mman.h>
-#include <stdarg.h>
-#include <stdint.h>
-#include <unistd.h>
-
-#include "platform/bionic/macros.h"
-#include "platform/bionic/page.h"
-
-extern "C" void* __mremap(void*, size_t, size_t, int, void*);
-
-void* mremap(void* old_address, size_t old_size, size_t new_size, int flags, ...) {
- // prevent allocations large enough for `end - start` to overflow
- size_t rounded = __BIONIC_ALIGN(new_size, page_size());
- if (rounded < new_size || rounded > PTRDIFF_MAX) {
- errno = ENOMEM;
- return MAP_FAILED;
- }
-
- void* new_address = nullptr;
- // The optional argument is only valid if the MREMAP_FIXED flag is set,
- // so we assume it's not present otherwise.
- if ((flags & MREMAP_FIXED) != 0) {
- va_list ap;
- va_start(ap, flags);
- new_address = va_arg(ap, void*);
- va_end(ap);
- }
- return __mremap(old_address, old_size, new_size, flags, new_address);
-}