Bug#1095479: exim4-config: Accepts mail for system users by default

[Andreas Metzler]

On 2025-02-08 Daniel Gröber <dxld at darkboxed.org> wrote:
> Package: exim4-config
> Version: 4.96-15+deb12u6
> Severity: normal
> X-Debbugs-Cc: dxld at darkboxed.org

> Hi Andreas,

> exim4-config's accepts mail for system users such as 'daemon' when
> local delivery is enabled. I find this unexpected and undesirable:
> who's ever going to read these? They just land in /var/mail and aren't
> forwarded to root like postmaster et al.

> I reproduced this on a fresh bookworm system with
> dc_eximconfig_configtype=smarthost, but on my real mailserver I
> deliver using dovecot lmtp (a common setup AFAIK), which (temp)rejects
> system users due to dovecot's first_valid_uid=1000 default. This
> causes (exclusively spam) for system users get stuck in the mailq
> which is ugly.

> Is this intentional? Do you think it's still useful?
[...]

Hello Daniel,

It has come up before:
file:///usr/share/doc/exim4-base/README.Debian.html
2.7. Handling incoming mail for local accounts with low UID

cu Andreas
-- 
`What a good friend you are to him, Dr. Maturin. His other friends are
so grateful to you.'
`I sew his ears on from time to time, sure'