Do you think it’s a bug in the dovecot code that calls winbind? Or in the samba based winbind code?
We have a fully patched CentOS system.
This case is definitely triggered as follows: Connect with Outlook Outlook brings in any new mail After maybe 30 seconds there are IMAP disconnect messages in maillog Then send a message to yourself. The message is sent and received, but the dovecot server crashes/panics Appears to be related to the CONT command And receiving NT_STATUS_WRONG_PASSWORD / NT_STATUS_LOGON_FAILURE
What I can’t figure out is that ntlm_auth always works from the command line, and IMAP is otherwise working to bring in new mail (so authenticating is working) - but it’s like a certain condition of sync’ing perhaps the Sent folder with the Inbox folder having two authentication events simultaneously is the issue, and the second one fails?
auth client connected auth client conencted client in: AUTH client in: AUTH client passdb out: CONT#0111 client passdb out: CONT#0111 client in: CONT<hidden> Got 'YR ..." from squid (length: 59). Starting GENSEC mechanism ntlmssp Starting GENSEC mechanism ntlmssp
Login for user [domain]\[user]@[workstation] failed due to [Wrong Password] ../auth/ntlmssp/ntlmssp_server.c:455: checking NTLMSSP password for domain/user failed: NT_STATUS_WRONG_PASSWORD GENSEC login failed: NT_STATUS_LOGON_FAILURE winbind(?,IP,<...>): user not authenticated: NT_STATUS_LOGON_FAILURE client in: CONT got 'KK ......' from squid . talloc: access after free error - first free may be at ../auth/ntlmssp/ntlmssp_server.c:457 Bad talloc magic value - access after free PANIC (pid ....): Bad talloc magic value - access after free Definitely welcome any debugging ideas and workarounds, because we have had to shut off IMAP and only use POP.
On Mar 29, 2016, at 1:46 PM, Timo Sirainen tss@iki.fi wrote:
On 16 Mar 2016, at 22:38, J Landwehr jlandwehr@icloud.com wrote:
Our new/fresh dovecot imap installation on CentOS (latest from yum repository, which is 2.2.10) is locking up with a panic on a consistent basis and denying service to subsequent clients. The behavior is repeatable. Have spent weeks debugging and trying different configurations with no success.
Specific /var/log/maillog error messages are:
12:06:54 dovecot: auth: Error: talloc: access after free error - first free may be at ../auth/ntlmssp/ntlmssp_server.c:457 12:06:54 dovecot: auth: Error: Bad talloc magic value - access after free 12:06:54 dovecot: auth: Error: PANIC (pid 2570): Bad talloc magic value - access after free
Looks like a bug in the winbind code.