io_uring/zcrx: improve types for size calculation

Make sure io_import_umem() promotes the type to long before calculating
the area size. While the area size is capped at 1GB by
io_validate_user_buf_range() and fits into an "int", it's still too
error prone.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Author: isilence

io_uring/zcrx.c

@@ -193,7 +193,7 @@ static int io_import_umem(struct io_zcrx_ifq *ifq,
 		return PTR_ERR(pages);
 
 	ret = sg_alloc_table_from_pages(&mem->page_sg_table, pages, nr_pages,
-					0, nr_pages << PAGE_SHIFT,
+					0, (unsigned long)nr_pages << PAGE_SHIFT,
 					GFP_KERNEL_ACCOUNT);
 	if (ret) {
 		unpin_user_pages(pages, nr_pages);