Package: lua-event
Version: 0.4.1-1
Severity: grave
Tags: upstream

When this binding is used with libevent 2.0 some errors are not handled
properly. An extract of the personal communication with the  maintainer of the
binding follows, giving precise details on how this bug affects, for example,
the prosody jabber server.

-- 8< ---------------------------------------------------------
From: Matthew Wild

The problem is caused by a combination of Lua's exception handling
(setjmp+longjmp) and some new re-entrant checks added to libevent.
When an error occurs inside an event callback Lua (at the C level)
jumps outs of libevent and up to the last set error handler, which in
Prosody is before libevent is called. After logging the error Prosody
heads back into libevent, but unfortunately libevent2 has an internal
flag to prevent entering it twice. Because the error jumped right
back, this flag is never unset and libevent immediately returns
(thinking it is already running). This triggers a shutdown in Prosody.

The consequence is that given any other bug that causes an error to be
thrown in Prosody (there aren't many, but they exist) it's possible to
remotely shut down a Prosody server that is using libevent, even from
an unauthenticated connection.

-- 8< ---------------------------------------------------------



-- System Information:
Debian Release: wheezy/sid
  APT prefers unstable
  APT policy: (500, 'unstable'), (500, 'testing'), (1, 'experimental')
Architecture: amd64 (x86_64)

Kernel: Linux 3.2.0-2-amd64 (SMP w/4 CPU cores)
Locale: LANG=en_US.utf8, LC_CTYPE=en_US.utf8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash

Versions of packages lua-event depends on:
ii  libc6              2.13-33
ii  libevent-2.0-5     2.0.19-stable-3
ii  lua-socket         2.0.2-8
ii  multiarch-support  2.13-33

lua-event recommends no packages.

lua-event suggests no packages.

-- no debconf information



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