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

From: Jiawen Wu
Date: Sun Oct 15 2023 - 23:07:00 EST


On Sunday, October 15, 2023 12:31 AM, Andrew Lunn wrote:
> 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.

Ah, I think I missed a line to print this string. I'm going to add it.