FPs and SA 3.2.0

[Paul Bijnens]

--[ UxBoD ]-- wrote:
> Even with just using one RBL I was getting non-spam items marked as SPAM. 
> When I made the change it marked SPAM messages correctly.

Don't be silly.

So you added this line;
    $temp = 0 unless $HitList[0] =~ /a-z/i;
And you did NOT add this line:
    $temp = 0 unless $HitList[0] =~ /[a-z]/i;

and afterwards you get a correct (non-empty, but no FP) list of RBLs?
What RBL did such a "marked SPAM message" got hit on?
The list "spamhaus-A-Z"  maybe?

Or you mean that the SPAM messages were no false positives anymore?
(Answer: Because SA had marked it like that, not because MailScanner
found it in a spam list added in MailScanner.conf having the string "a-z".)

Read and understand before you reply!  Please!



> On Mon, 21 May 2007 19:28:01 +0200, Paul Bijnens
> <Paul.Bijnens at xplanation.com> wrote:
>> On 2007-05-21 17:10, Julian Field wrote:
>>>
>>> Paul Bijnens wrote:
>>>> On 2007-05-16 17:41, Julian Field wrote:
>>>>> I'll put it in the main codebase then. Perl has some very subtle bugs
>> in
>>>>> it...
>>>>>
>>>> I believe I don't need to teach perl to Julian (rather the other way
>>>> around :-) ), but anyway...
>>>
>>>>>>>>
>>>>>>>>>   # JKF 3/10/2005
>>>>>>>>>   my $temp = @HitList;
>>>>>>>>>   $temp = $temp + 0;
>>>>>>>>>   $temp = 0 unless $HitList[0] =~ /a-z/i;
>>>>>>>>>   return ($temp, join(', ', @HitList));
>>>>>>>>> }
>>>>>>>>>
>>>>>>>>> Let's see if that helps. According to the book, the 2 middle lines
>>>>>>>>> shouldn't be needed at all.
>>>>>>>>>
>>>> To me this seems like the array @HitList contains an empty or undef
>>>> value.  The match against "/[a-z]/i"   (or was that really intended
>>>> "/a-z/i"??)
>>> No, your version would match against any string that contained the
>>> string "a-z" in it (in upper or lower case).
>> Excuse me :-) but "/a-z/i" is your version and that will search for
>> a string "a-z" lower or upper case.  My version, "/[a-z]/i", will match
>> a name with at least one letter in it.  Which is what you're trying to
>> do, I believe.
>> You're effectively removing any RBL hits now, which is the main reason
>> why no more FP's got hit by the current beta tester(-s? -- only one
>> person as far I see had the problem).
>>
>> http://lists.mailscanner.info/pipermail/mailscanner/2007-May/073331.html
>>
>> I'm still interested in the exact list of RBLs in his config.
>> Does it happen when 1 list is added? Two?  Some particular list only?
>>
>>
>>>>  just hides the source of the real error: getting an empty
>>>> value for RBL name.
>>> If I printed the string of @HitList it turned out to have no contents,
>> How?    Something like:
>>
>>     @HitList = ( "" );	# somehow this ended up in the list
>>     $temp = @HitList;
>>     warn("HitList contains $temp entries: '@HitList'\n");
>>
>> No (visible) contents, but still one element in the array.
>>
>>
>>> so the scalar of it should have been zero. I have seen the problem of
>>> "0" not always equaling zero a few other times, hence the addition of
>>> zero to it to try to fix it, which has normally fixed the problem
>> You can have that problem with "" or undef, acting as 0 in calculations
>> but not showing up as a "0" when printed. Indeed fixed by explicitly
>> converting to number by adding "+ 0".
>>
>>> elsewhere. The new modification has only been recently needed, the code
>>> has worked perfectly well for years (the previous version was very old
>>> code). If it had been needed before, people would have been complaining
>>> loudly about this for the past few years, and they haven't been. So if
>>> the start of the list doesn't contain a letter (all RBL names must
>>> contain at least 1 letter or they wouldn't work) then the list must
>>> actually be empty, so I force it to return zero.
>> So we have to find out where the list element comes from that does
>> not contain a letter, but is empty instead.  Instead of covering up the
>> bug here.  (Still not convinced it is a perl bug.)
>> Maybe most people use some RBLs at the MTA-level to block the incoming
>> mail completely and/or use other RBLs in SA for scoring, and let the
>> spam list entry in MailScanner empty.  Or the bug happens only on
>> a timeout, like suggested in the OP problem, or only for certain
>> combinations of timeout values, etc, etc.
>>
>>
>>>> Now finding out where the empty value is coming from, is -- at my
>>>> current understanding of the code -- not yet successful.
>>> Yes. I have another demo of a Perl bug which I'll post for you if you
>>> like. Perl is not bug-free.
>> Sure not.  But, speaking for myself, it's usually in my own
>> programs, and not in the perl compiler, that I find the bugs.  :-)


-- 
Paul Bijnens, xplanation Technology Services        Tel  +32 16 397.511
Technologielaan 21 bus 2, B-3001 Leuven, BELGIUM    Fax  +32 16 397.512
http://www.xplanation.com/          email:  Paul.Bijnens at xplanation.com
***********************************************************************
* I think I've got the hang of it now:  exit, ^D, ^C, ^\, ^Z, ^Q, ^^, *
* F6, quit, ZZ, :q, :q!, M-Z, ^X^C, logoff, logout, close, bye, /bye, *
* stop, end, F3, ~., ^]c, +++ ATH, disconnect, halt,  abort,  hangup, *
* PF4, F20, ^X^X, :D::D, KJOB, F14-f-e, F8-e,  kill -1 $$,  shutdown, *
* init 0, kill -9 1, Alt-F4, Ctrl-Alt-Del, AltGr-NumLock, Stop-A, ... *
* ...  "Are you sure?"  ...   YES   ...   Phew ...   I'm out          *
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