gralloc: Fix issue with mmap/munmap meta due to reserved size

Fix possible security issue which can happen if client changes
reserved size in meta data. This can cause wrong size munmap.

Bug:238103940
Change-Id: Ie8c226d9e7d1d0dc481d026ccd454a1db46fb915
Signed-off-by: linjoey <linjoey@google.com>
(cherry picked from commit c9a0d7b113fd908949b6a3a9ea247d85ba07c3c7)
Merged-In: Ie8c226d9e7d1d0dc481d026ccd454a1db46fb915
1 file changed