Re: confusion about lists always expanding.

On 2026/07/14 6:44 AM, Jasen Betts via Exim-users wrote:
> On 2026-05-27, Jeremy Harris via Exim-users <[email protected]> wrote:
>> On 2026/05/12 11:37 PM, Jasen Betts via Exim-users wrote:
>>> I have something like
>>>    
>>> (0)     ${if inlist{$local_part@$domain}{<,$acl_m_specialrcpts}}
>>>
>>> It mostly works, but if $acl_m_specialrcpts which is tainted
>>> contains a '$' I get a panic about expanding taited data,
At first sight, the inlist should work.  I'll investigate.
I can duplicate the issue under expansion-test (-be).

For now, use the forany construct (less efficient as well as
more complex to write...)

Not sure why you have the extra leading character in your
acl_m_specialrcpts; it's certainly adding complexity here.


> Also should there be a warning about expanding tainted data when it
> does not contain a '$'?

Probably a pre-scan of the string-for-expansion found no $, so the expansion
was bypassed - and the check for taint is at the head of the routine
doing the latter.  Maybe it should indeed have whined... I suspect there
are such pre-checks in multiple places which could do with consolidation.

However, this is a consistency issue rather than a security one
so low priority.
-- 
Cheers,
   Jeremy

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