libkmod: Prevent ouf of boundary access

Follow up of aad7c69, which fixes the same issue in another function.

Signed-off-by: Tobias Stoeckmann <[email protected]>
Reviewed-by: Emil Velikov <[email protected]>
Link: #248
Signed-off-by: Lucas De Marchi <[email protected]>

Author: stoeckmann

libkmod/libkmod-module.c

@@ -1527,7 +1527,7 @@ KMOD_EXPORT long kmod_module_get_size(const struct kmod_module *mod)
 		size = value;
 		break;
 eat_line:
-		while (line[len - 1] != '\n' && fgets(line, sizeof(line), fp))
+		while (len > 0 && line[len - 1] != '\n' && fgets(line, sizeof(line), fp))
 			len = strlen(line);
 	}
 	fclose(fp);