clear_eof 'decode_filter' with enabled filter...

[brian moore]

Hrrrm... this is interesting.  A silly PGP5 user sent me a smear of
text/plain, text/html and a JPEG of a piece of paper (did I say he was
silly?) and GPG is able to decrypt it just fine, but spits out the above
subject line and coredumps in the process.

I used the handy-dandy '--debug 16' to see just what was going on (I
won't bore you with all the details, but enough to show the iobuf
stack):

<bunch of snippage>

gpg: DBG: iobuf-5.6: push 'block_filter'
gpg: DBG:       chain: 5.6 'block_filter'
gpg: DBG:       chain: 5.5 'compress_filter'
gpg: DBG:       chain: 5.4 'block_filter'
gpg: DBG:       chain: 5.3 'decode_filter'
gpg: DBG:       chain: 5.2 '(null)'
gpg: DBG:       chain: 5.1 'armor_filter'
gpg: DBG:       chain: 5.0 'file_filter'
gpg: DBG: init block_filter 0x80d176c
gpg: DBG: free block_filter 0x80d4604
:literal data packet:
        mode b, created 3221225472, name="eud91B5.TMP",
        raw data: 0 bytes
gpg: DBG: free block_filter 0x80d176c
gpg: DBG: iobuf-5.6: pop '(null)'
gpg: DBG: iobuf-5.5: filter eof
gpg: DBG: iobuf-5.5: pop '(null)'
gpg: DBG: iobuf-5.4: filter eof
gpg: DBG: iobuf-5.4: pop '(null)'
gpg: iobuf-5.3: clear_eof 'decode_filter' with enabled filter
gpg: iobuf-5.3: clear_eof 'decode_filter' with no EOF pending
gpg: DBG: iobuf-5.3: pop 'decode_filter'

gpg: Segmentation fault caught ... exiting

It seems to be breaking at:
Breakpoint 4, iobuf_pop_filter (a=0x80d528c, f=0, ov=0x0) at iobuf.c:754
754         if( a->usage == 2 && (rc=iobuf_flush(b)) ) {
(gdb) next
759         if( (rc = b->filter(b->filter_ov, IOBUFCTRL_FREE, b->chain,
(gdb) print b
$4 = 0x80d4274
(gdb) print b->filter
$5 = (int (*)()) 0

-- 
Brian Moore                       | "The Zen nature of a spammer resembles
      Sysadmin, C/Perl Hacker     |  a cockroach, except that the cockroach
      Usenet Vandal               |  is higher up on the evolutionary chain."
      Netscum, Bane of Elves.                 Peter Olson, Delphi Postmaster