Btrfs: NUL-terminate path buffer in DEV_INFO ioctl result

A device with name of length BTRFS_DEVICE_PATH_NAME_MAX or longer would not be NUL-terminated in the DEV_INFO ioctl result buffer.

Signed-off-by Jim Meyering <[email protected]>

A device with name of length BTRFS_DEVICE_PATH_NAME_MAX or longer would not be NUL-terminated in the DEV_INFO ioctl result buffer.

Signed-off-by Jim Meyering <[email protected]>

---
 fs/btrfs/ioctl.c |    1 +
 1 file changed, 1 insertion(+)

fs/btrfs/ioctl.c +1 -1

index 18cc23d..1578676 100644
@@ -2258,16 +2258,17 @@ static long btrfs_ioctl_dev_info(struct btrfs_root *root, void __user *arg)
 		goto out;
 	}
 
 	di_args->devid = dev->devid;
 	di_args->bytes_used = dev->bytes_used;
 	di_args->total_bytes = dev->total_bytes;
 	memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid));
 	strncpy(di_args->path, dev->name, sizeof(di_args->path));
+	di_args->path[sizeof(di_args->path) - 1] = 0;
 
 out:
 	if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args)))
 		ret = -EFAULT;
 
 	kfree(di_args);
 	return ret;
 }
--

1.7.10.336.gc5e31