Bug 744799

Description of problem:

Since the upgrade on aug 19, 2011 to dovecot-0.99.11-10.EL4, we get suddenly crashes when accessing certain folders.

The relevant entries in dovecot log:

  imap-login: Oct 09 11:31:31 Info: Login: paulb [::ffff:10.11.12.90]
  imap(paulb): Oct 09 11:37:05 Error: Corrupted index file /home/paulb/Maildir/.Arch-2007/.imap.index: Duplicated message 1318152995.P1683Q919M941772.xxx.yyy.com
  imap(paulb): Oct 09 11:40:19 Panic: file lib.c: line 37 (nearest_power): assertion failed: (num <= ((size_t)1 << (BITS_IN_SIZE_T-1)))

It seems to panic when rebuilding the index file.
From then on, access to that folder consistently crashes with the same panic line.

Some googling around brought up this:

  http://www.somerandomstuff.com/2011/09/30/dovecot-crash/

which seems to imply that the presence of a message with missing final boundary line seems to the cause. (missing a "--" at the end or even completely missing)

When searching my whole folder, there were indeed a few messages with a completely missing final boundary line.  Adding the mime boundary line manually fixed the problem.


Version-Release number of selected component (if applicable):

dovecot-0.99.11-10.EL4

How reproducible:


Steps to Reproduce:

1. Create a maildir folder on the server, populating it with a few messages, having at least a few one with attachments. (Easily done with an IMAP server, thunderbird and copying some existing messages.)

2. On the server, using a editor, remove the final mime boundary line on one of them (e.g. simulating the result of "no space left on device" when writing the message -- that is probably how it ended up there in 2007 in my folder). Try to find one, so that, when dovecot reads the messages, this one is not the last one in it's list.

3. Remove the .imap.index* files, so that Dovecot tries to rebuild them on access.

4.  Using thunderbird, subscribe to the folder, access it, and watch /var/log/dovecot.log