Merge changes I73a39c6d,Iab2af242
* changes:
Fix test build break.
extend the PTRDIFF_MAX size check to mremap
diff --git a/libc/bionic/mmap.cpp b/libc/bionic/mmap.cpp
index 9bc80a2..8301445 100644
--- a/libc/bionic/mmap.cpp
+++ b/libc/bionic/mmap.cpp
@@ -27,6 +27,7 @@
*/
#include <errno.h>
+#include <stdint.h>
#include <sys/mman.h>
#include <unistd.h>
diff --git a/libc/bionic/mremap.cpp b/libc/bionic/mremap.cpp
index 4892b1d..6653d43 100644
--- a/libc/bionic/mremap.cpp
+++ b/libc/bionic/mremap.cpp
@@ -26,12 +26,24 @@
* SUCH DAMAGE.
*/
+#include <errno.h>
#include <sys/mman.h>
#include <stdarg.h>
+#include <stdint.h>
+#include <unistd.h>
+
+#include "private/bionic_macros.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.
diff --git a/tests/sys_mman_test.cpp b/tests/sys_mman_test.cpp
index dffb646..ddb6c77 100644
--- a/tests/sys_mman_test.cpp
+++ b/tests/sys_mman_test.cpp
@@ -17,6 +17,7 @@
#include <gtest/gtest.h>
#include <sys/mman.h>
+#include <sys/user.h>
#include <sys/types.h>
#include <unistd.h>
@@ -219,3 +220,15 @@
TEST(sys_mman, mremap) {
ASSERT_EQ(MAP_FAILED, mremap(nullptr, 0, 0, 0));
}
+
+const size_t huge = size_t(PTRDIFF_MAX) + 1;
+
+TEST(sys_mman, mmap_PTRDIFF_MAX) {
+ ASSERT_EQ(MAP_FAILED, mmap(nullptr, huge, PROT_NONE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0));
+}
+
+TEST(sys_mman, mremap_PTRDIFF_MAX) {
+ void* map = mmap(nullptr, PAGE_SIZE, PROT_NONE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+ ASSERT_NE(MAP_FAILED, map);
+ ASSERT_EQ(MAP_FAILED, mremap(map, PAGE_SIZE, huge, MREMAP_MAYMOVE));
+}