diff --git a/23da0fa1b30cc11bcc1d467674a0950c527e9ff1.patch b/23da0fa1b30cc11bcc1d467674a0950c527e9ff1.patch
new file mode 100644
index 0000000..6bf1501
--- /dev/null
+++ b/23da0fa1b30cc11bcc1d467674a0950c527e9ff1.patch
@@ -0,0 +1,28 @@
+From 23da0fa1b30cc11bcc1d467674a0950c527e9ff1 Mon Sep 17 00:00:00 2001
+From: Timo Sirainen <timo.sirainen@dovecot.fi>
+Date: Sat, 6 Jan 2018 21:22:11 +0200
+Subject: [PATCH] ostream-zlib: Ignore missing finish if parent stream is
+ ignoring errors
+
+This fixes panic with imap_zlib plugin when client enables the IMAP COMPRESS
+extension and disconnects:
+
+Panic: file ostream-zlib.c: line 36 (o_stream_zlib_close): assertion failed: (zstream->ostream.finished || zstream->ostream.ostream.stream_errno != 0)
+---
+ src/lib-compression/ostream-zlib.c | 3 ++-
+ 1 file changed, 2 insertions(+), 1 deletion(-)
+
+diff --git a/src/lib-compression/ostream-zlib.c b/src/lib-compression/ostream-zlib.c
+index 848ecb7b89..e0b9a91416 100644
+--- a/src/lib-compression/ostream-zlib.c
++++ b/src/lib-compression/ostream-zlib.c
+@@ -33,7 +33,8 @@ static void o_stream_zlib_close(struct iostream_private *stream,
+ 	struct zlib_ostream *zstream = (struct zlib_ostream *)stream;
+ 
+ 	i_assert(zstream->ostream.finished ||
+-		 zstream->ostream.ostream.stream_errno != 0);
++		 zstream->ostream.ostream.stream_errno != 0 ||
++		 zstream->ostream.error_handling_disabled);
+ 	(void)deflateEnd(&zstream->zs);
+ 	if (close_parent)
+ 		o_stream_close(zstream->ostream.parent);
diff --git a/dovecot23.changes b/dovecot23.changes
index da273b6..114c38a 100644
--- a/dovecot23.changes
+++ b/dovecot23.changes
@@ -1,3 +1,8 @@
+-------------------------------------------------------------------
+Wed Mar  7 12:25:51 UTC 2018 - mrueckert@suse.de
+
+- added 23da0fa1b30cc11bcc1d467674a0950c527e9ff1.patch
+
 -------------------------------------------------------------------
 Wed Mar  7 12:10:44 UTC 2018 - mrueckert@suse.de
 
diff --git a/dovecot23.spec b/dovecot23.spec
index 21b92c2..f69f7c9 100644
--- a/dovecot23.spec
+++ b/dovecot23.spec
@@ -134,6 +134,7 @@ Source9:        dovecot-2.3-pigeonhole.configfiles
 Patch:          dovecot-2.3.0-dont_use_etc_ssl_certs.patch
 Patch1:         dovecot-2.3.0-better_ssl_defaults.patch
 Patch2:         dovecot-2.3.0.1-over-quota-lmtp-crash.patch
+Patch3:         23da0fa1b30cc11bcc1d467674a0950c527e9ff1.patch
 Summary:        IMAP and POP3 Server Written Primarily with Security in Mind
 License:        BSD-3-Clause AND LGPL-2.1-or-newer AND MIT
 Group:          Productivity/Networking/Email/Servers
@@ -314,6 +315,7 @@ dovecot tree.
 %patch -p1
 %patch1 -p1
 %patch2 -p1
+%patch3 -p1
 gzip -9v ChangeLog
 # Fix plugins dir.
 sed -i 's|#mail_plugin_dir = /usr/lib/dovecot|mail_plugin_dir = %{_libdir}/dovecot/modules|' doc/example-config/conf.d/10-mail.conf