Re: [PATCH] staging: greybus: fix string termination in firmware sample

[Dan Carpenter]

On Mon, Nov 02, 2026 at 07:44:09PM +0530, Kurmapu Sai Devansh Prasad wrote:
> >From 9114eb9d60f2c4a52f05e3a33b0d6b8ca4856cac Mon Sep 17 00:00:00 2001
> From: Kurmapu Sai Devansh Prasad <btech10487.26@xxxxxxxxxxxxxx>
> Date: Mon, 2 Nov 2026 19:11:09 +0530
> Subject: [PATCH] staging: greybus: fix string termination in firmware sample
> 
> The firmware_tag string copied via strncpy() is not guaranteed to be
> NUL-terminated if the source string is exactly the size of the destination
> buffer. This can lead to a buffer over-read.
> 
>  Since alternatives like strscpy_pad cannot be used in user space
> sample code, we can make it  safer by limiting the copy size to
> MAX_SIZE - 1 and explicitly assigning the last byte to be a NUL
> terminator. This ensures the string is always
> safely terminated before being passed to the ioctl.

In user space, using strncpy() is fine.

> 
> Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings
> 
> This is my very first patch to the Linux kernel! I've been learning the
> process and would deeply appreciate any feedback from the maintainers.

Put this sort of unrelated conversational stuff under the --- cut off

> 
> Signed-off-by: Kurmapu Sai Devansh Prasad <btech10487.26@xxxxxxxxxxxxxx>
> ---
  ^^^
here.  So that it doesn't get saved into the kernel git log.

The patch is pretty badly corrupted and doesn't apply.  Read the first
two paragraph of Documentation/process/email-clients.rst

regards,
dan carpenter