util/mmap-alloc: check parameter before using

Signed-off-by: Cao jin <caoj.fnst@cn.fujitsu.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
This commit is contained in:
Cao jin 2016-11-02 21:44:46 +08:00 committed by Michael Tokarev
parent 8907379204
commit 4a3ecf201a

View File

@ -12,6 +12,7 @@
#include "qemu/osdep.h"
#include "qemu/mmap-alloc.h"
#include "qemu/host-utils.h"
#define HUGETLBFS_MAGIC 0x958458f6
@ -61,18 +62,18 @@ void *qemu_ram_mmap(int fd, size_t size, size_t align, bool shared)
#else
void *ptr = mmap(0, total, PROT_NONE, MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
#endif
size_t offset = QEMU_ALIGN_UP((uintptr_t)ptr, align) - (uintptr_t)ptr;
size_t offset;
void *ptr1;
if (ptr == MAP_FAILED) {
return MAP_FAILED;
}
/* Make sure align is a power of 2 */
assert(!(align & (align - 1)));
assert(is_power_of_2(align));
/* Always align to host page size */
assert(align >= getpagesize());
offset = QEMU_ALIGN_UP((uintptr_t)ptr, align) - (uintptr_t)ptr;
ptr1 = mmap(ptr + offset, size, PROT_READ | PROT_WRITE,
MAP_FIXED |
(fd == -1 ? MAP_ANONYMOUS : 0) |