[pve-devel] [PATCH installer] fetch-answer: encode unsafe characters in partition label

[Christoph Heiss]

Good catch & thanks for tackeling this!

Also tested it with a simple whitespace character.

Tested-by: Christoph Heiss <c.heiss at proxmox.com>
Reviewed-by: Christoph Heiss <c.heiss at proxmox.com>

On Tue, Nov 19, 2024 at 03:59:34PM +0100, Filip Schauer wrote:
> Ensure potentially unsafe characters in the partition label are encoded,
> preventing the installer from failing to find the answer partition when
> the label contains whitespaces or !"$%&'()*,/;<>?[\]^`{|}~
> [..]
> ---
>  .../src/fetch_plugins/partition.rs            | 30 ++++++++++++++-----
>  1 file changed, 22 insertions(+), 8 deletions(-)
> [..]
> @@ -52,20 +65,21 @@ fn path_exists_logged(file_name: &str, search_path: &str) -> Option<PathBuf> {
>  /// * `partlabel_source` - Partition Label, used for matching, in the exact, upper and lower case
>  /// * `search_path` - Path where to search for the partition label
>  fn scan_partlabels(partlabel: &str, search_path: &str) -> Result<PathBuf> {
> -    if let Some(path) = path_exists_logged(partlabel, search_path) {
> -        info!("Found partition with label '{partlabel}'");
> +    let partlabel_enc = encode_partlabel(partlabel);
> +    if let Some(path) = path_exists_logged(&partlabel_enc, search_path) {
> +        info!("Found partition with label '{partlabel_enc}'");

I think the original, non-encoded partition label should be printed
here.

As it would be somewhat surprising to users/administrators to suddenly
see some partition label being searched that what the specified -- thus
considering this as an internal implementation detail, not public
interface.

>          return Ok(path);
>      }
>
> -    let partlabel_upper_case = partlabel.to_uppercase();
> -    if let Some(path) = path_exists_logged(&partlabel_upper_case, search_path) {
> -        info!("Found partition with label '{partlabel_upper_case}'");
> +    let partlabel_upper_case_enc = encode_partlabel(&partlabel.to_uppercase());
> +    if let Some(path) = path_exists_logged(&partlabel_upper_case_enc, search_path) {
> +        info!("Found partition with label '{partlabel_upper_case_enc}'");

.. same here ..

>          return Ok(path);
>      }
>
> -    let partlabel_lower_case = partlabel.to_lowercase();
> -    if let Some(path) = path_exists_logged(&partlabel_lower_case, search_path) {
> -        info!("Found partition with label '{partlabel_lower_case}'");
> +    let partlabel_lower_case_enc = encode_partlabel(&partlabel.to_lowercase());
> +    if let Some(path) = path_exists_logged(&partlabel_lower_case_enc, search_path) {
> +        info!("Found partition with label '{partlabel_lower_case_enc}'");

.. and here.