diff --git a/drivers/char/mem.c b/drivers/char/mem.c
index 1ccbe94..2ca6d78 100644
--- a/drivers/char/mem.c
+++ b/drivers/char/mem.c
@@ -745,7 +745,7 @@
 		offset += file->f_pos;
 	case SEEK_SET:
 		/* to avoid userland mistaking f_pos=-9 as -EBADF=-9 */
-		if ((unsigned long long)offset >= ~0xFFFULL) {
+		if (IS_ERR_VALUE((unsigned long long)offset)) {
 			ret = -EOVERFLOW;
 			break;
 		}