uffd: Fix page fault address

The page_size() returns unsigned int value that is after "bitwise not"
is promoted to unsigned long (msg->arg.pagefault.address) value. Sinc
e the value is unsigned promotion is done with 0 MSB that results in
lost of MSB pagefault address bits. Cast page_size to unsigned long
first to avoid such situation.

Signed-off-by: Vladislav Khmelevsky <och95@yandex.ru>

criu/uffd.c

@@ -1155,7 +1155,7 @@ static int handle_page_fault(struct lazy_pages_info *lpi, struct uffd_msg *msg)
 	int ret;
 
 	/* Align requested address to the next page boundary */
-	address = msg->arg.pagefault.address & ~(page_size() - 1);
+	address = msg->arg.pagefault.address & ~((unsigned long)page_size() - 1);
 	lp_debug(lpi, "#PF at 0x%llx\n", address);
 
 	if (is_page_queued(lpi, address))