bogofilter closing stdin prematurely in passthrough mode

[Tomaž Šolc]

Hi

I have a bogofilter setup where procmail pipes messages through 
bogofilter for sorting. I've been looking into a problem where a certain 
email causes procmail to error out ("error while writing to bogofilter") 
and repeatedly defer the delivery.

It appears that the reason is that bogofilter prematurely closes stdin 
and exits while procmail still has bytes to write. Indeed, if I just cat 
the offending email through "bogofilter -p" the email printed on stdout 
is truncated somewhere in the middle.

Otherwise bogofilter appears to work normally. It doesn't return an 
error code. There's no segfault. The only weird thing I see is that if I 
do a strace it attempts to do an invalid seek on fd=0 before it exits, 
but this might be benign.

I think the email is hitting somekind of a token or input buffer limit. 
It has a few very long sequences of U+3164 "HANGUL FILLER" characters. 
I've been able to reproduce the problem by creating an email with such a 
sequence. Bogofilter cuts it off after 3640 characters (but, for 
example, it will not cut off an identical email with an ascii "a" 
instead of U+3164).

This is with bogofilter 1.2.5 as packaged in Debian Bookworm.

I'll check if the same issue appears with 1.3.0 once I get it running.

Best regards
Tomaž