ubi: Reserve sufficient buffer length for the input mask

Because the mask received by the emulate_failures interface
is a 32-bit unsigned integer, ensure that there is sufficient
buffer length to receive and display this value.
Signed-off-by: ZhaoLong Wang <wangzhaolong1@huawei.com>
Reviewed-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

drivers/mtd/ubi/debug.c

@@ -332,7 +332,7 @@ static ssize_t dfs_file_read(struct file *file, char __user *user_buf,
 	struct dentry *dent = file->f_path.dentry;
 	struct ubi_device *ubi;
 	struct ubi_debug_info *d;
-	char buf[8];
+	char buf[16];
 	int val;
 
 	ubi = ubi_get_device(ubi_num);
@@ -400,7 +400,7 @@ static ssize_t dfs_file_write(struct file *file, const char __user *user_buf,
 	struct ubi_device *ubi;
 	struct ubi_debug_info *d;
 	size_t buf_size;
-	char buf[8] = {0};
+	char buf[16] = {0};
 	int val;
 
 	ubi = ubi_get_device(ubi_num);