# Re: \[PATCH RFC net-next\] ptp: Add file permission checks on PHC chardevs

- From: Richard Cochran \<richardcochran@gmail.com\>
- Date: 2025-02-02 06:24:30 
- List: netdev
- Page: https://ratatoskr.run/netdev/2025/02/11317651
- Thread: https://ratatoskr.run/netdev/2025/01/11317598/t.md

```text
On Fri, Jan 31, 2025 at 06:29:23PM +0000, Wojtek Wasko wrote:
> Udev sets strict 600 permissions on /dev/ptp* devices, preventing

Udev is user space, isn't it?

> unprivileged users from accessing the time [1]. This patch enables
> more granular permissions and allows readonly access to the PTP clocks.
> 
> Add permission checking for ioctls which modify the state of device.
> Notably, require WRITE for polling as it is only used for later reading
> timestamps from the queue (there is no peek support). POSIX clock
> operations (settime, adjtime) are checked in the POSIX layer.

This change log is not comprehensible.
A proper change log has three parts:

1. context

2. problem   (What is the issue?)

3. solution  (How does the patch address the issue?)

Thanks,
Richard
```