[PATCH v2] app/testpmd: fix devargs format in port attach

[Stephen Hemminger]

On Thu, 30 Oct 2025 19:17:34 +0200
Gregory Etelson <getelson at nvidia.com> wrote:

> diff --git a/app/test-pmd/testpmd.c b/app/test-pmd/testpmd.c
> index 2360da3a48..a2280d38d3 100644
> --- a/app/test-pmd/testpmd.c
> +++ b/app/test-pmd/testpmd.c
> @@ -3431,6 +3431,7 @@ convert_pci_address_format(const char *identifier, char *pci_buffer, size_t buf_
>  		return NULL;
>  
>  	rte_pci_device_name(&pci_addr, pci_buffer, buf_size);
> +	sprintf(pci_buffer + strlen(pci_buffer), ",%s", da.args);
>  	return pci_buffer;
>  }
>  

To avoid any possiblity of overflow, please us snprintf and adjust.
Something like:
	rte_pci_device_name(&pci_addr, pci_buffer, buf_size);
	size_t pci_len = strlen(pci_buffer);
	snprintf(pci_buffer + pci_len, buf_size - pci_len, "%,%s", da.args);