nnrpd dies

[David E Mussulman]

Hey gang,

So as of Friday evening sometime, my set-it-and-forget-it news server
stopped accepting NNRP requests.  From the logs (and my client
experience), it accepts the connection, gets good/valid authentication
info, and then dies.  I don't know what would have happened to break
this (but for good measure, I patched up the latest CentOS 5.6 and
rebooted, to no avail.)

I checked if our kerberos against AD auth was failing, but that seemed
to work okay.  (Manually running the auth_krb5 command succeeds.)  I
double-checked our perl_access script, and that's running okay too.  If
I login with bad credentials, I'm denied as expected and the connection
stays up.  If I login successfully, the connection drops.

If I turn on tracing with nnrpd, here's what I see:

bash-3.2$ ./nnrpd -p 8001 -D -f -t
*** glibc detected *** - nnrpd: dcs-news1.cs.: malloc(): memory
corruption: 0x09b04308 ***
======= Backtrace: =========
/lib/libc.so.6[0xd7a3fd]
/lib/libc.so.6(__libc_malloc+0x67)[0xd7bfb7]
/lib/libc.so.6(open_memstream+0x26)[0xd6fca6]
/lib/libc.so.6(__vsyslog_chk+0x76)[0xdde5d6]
/lib/libc.so.6(syslog+0x2a)[0xddeb9a]
- nnrpd: dcs-news1.cs.[0x80606c4]
- nnrpd: dcs-news1.cs.[0x8060b5b]
- nnrpd: dcs-news1.cs.(PERMgetpermissions+0x540)[0x8061940]
- nnrpd: dcs-news1.cs.(CMDauthinfo+0x391)[0x8057e01]
- nnrpd: dcs-news1.cs.(main+0x1089)[0x805cd59]
/lib/libc.so.6(__libc_start_main+0xdc)[0xd25e9c]
- nnrpd: dcs-news1.cs.[0x8052801]
======= Memory map: ========
(snipped for brevity)

Can anyone help me troubleshoot what's wrong, and how I can fix it?
News is dead in the water here, and I'm really not sure why.

TIA,
Dave