Re: [PATCH bpf-next] bpftool: bash-completion: Add nopasswd sudo prefix for bpftool

[Quentin Monnet <qmo@kernel.org>]

2025-02-12 18:14 UTC+0800 ~ Rong Tao <rtoax@foxmail.com>
> From: Rong Tao <rongtao@cestc.cn>
> 
> In the bpftool script of bash-completion, many bpftool commands require
> superuser privileges to execute. Otherwise, Operation not permission will
> be displayed. Here, we check whether ordinary users are exempt from
> entering the sudo password. If so, we need to add the sudo prefix to the
> bpftool command to be executed. In this way, we can obtain the correct
> command completion content instead of the wrong one.
> 
> For example, when updating array_of_maps, the wrong 'hex' is completed:
> 
>     $ sudo bpftool map update name arr_maps key 0 0 0 0 value [tab]
>     $ sudo bpftool map update name arr_maps key 0 0 0 0 value hex
> 
> However, what we need is "id name pinned". Similarly, there is the same
> problem in getting the map 'name' and 'id':
> 
>     $ sudo bpftool map show name [tab] < get nothing
>     $ sudo bpftool map show id [tab]   < get nothing
> 
> This commit fixes the issue.
> 
>     $ sudo bpftool map update name arr_maps key 0 0 0 0 value [tab]
>     id      name    pinned
> 
>     $ sudo bpftool map show name
>     arr_maps         cgroup_hash      inner_arr1       inner_arr2
> 
>     $ sudo bpftool map show id
>     11    1383  4091  4096
> 
> Signed-off-by: Rong Tao <rongtao@cestc.cn>

Hi, thanks for the patch.

I agree it's annoying to have a partially-working completion for
non-root users, however, I don't feel very comfortable introducing calls
to "sudo" in bash completion, without the user noticing. For what it's
worth, I searched other bash completion files (from
https://github.com/scop/bash-completion/) and I can't find any of them
running sudo to help complete commands, so it doesn't seem to be
something usual in completion. I think I'd rather keep the current state
(or fix the first example to have the right keywords displayed but
without running sudo).

Quentin