Re: [PATCH] net: txgbe: replace deprecated strncpy with strscpy

From: Andrew Lunn
Date: Sat Oct 14 2023 - 12:31:33 EST


On Thu, Oct 12, 2023 at 09:20:04PM +0000, Justin Stitt wrote:
> strncpy() is deprecated for use on NUL-terminated destination strings
> [1] and as such we should prefer more robust and less ambiguous string
> interfaces.
>
> Based on usage part_str usage within txgbe_read_pba_string(), we expect
> part_str to be NUL-terminated but not necessarily NUL-padded:
> | /* put a null character on the end of our string */
> | pba_num[10] = '\0';
>
> Interestingly, part_str is not used after txgbe_read_pba_string():
> | ...
> | err = txgbe_read_pba_string(wx, part_str, TXGBE_PBANUM_LENGTH);
> | if (err)
> | strscpy(part_str, "Unknown", sizeof(part_str));
> |
> | netif_info(wx, probe, netdev, "%pM\n", netdev->dev_addr);
> |
> | return 0;
> |
> |err_remove_phy:
> | txgbe_remove_phy(txgbe);
> |err_release_hw:
> | wx_clear_interrupt_scheme(wx);
> | wx_control_hw(wx, false);
> |err_free_mac_table:
> | kfree(wx->mac_table);
> |err_pci_release_regions:
> | pci_release_selected_regions(pdev,
> | pci_select_bars(pdev, IORESOURCE_MEM));
> |err_pci_disable_dev:
> | pci_disable_device(pdev);
> | return err;
> |}
> ... this means this strncpy (or now strscpy) is probably useless. For
> now, let's make the swap to strscpy() as I am not sure if this is truly
> dead code or not.

Hi Julian

I agree, this looks like dead code.

Jiawen, please could you submit a patch cleaning this up. Either swap
to strscpy() and make use of the string, or delete it all.


Andrew

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