[Dovecot] Fixes CVE-2017-15132 - take 2

data/Dockerfiles/dovecot/Dockerfile

@@ -65,7 +65,9 @@ RUN apt-get update && apt-get -y --no-install-recommends install \
 
 RUN curl https://www.dovecot.org/releases/2.2/dovecot-$DOVECOT_VERSION.tar.gz | tar xvz  \
   && cd dovecot-$DOVECOT_VERSION \
-  && sed '/call_callback(request, AUTH_REQUEST_STATUS_ABORT, NULL, NULL);/a   pool_unref(&request->pool);' src/lib-auth/auth-client-request.c \
+  && curl -o src/lib-auth/auth-client-request.c https://mailcow.email/dovecot-patch1/auth-client-request.c \
+  && curl -o src/lib-auth/auth-server-connection.c https://mailcow.email/dovecot-patch1/auth-server-connection.c \
+  && curl -o src/lib-auth/auth-server-connection.h https://mailcow.email/dovecot-patch1/auth-server-connection.h \
   && ./configure --with-mysql --with-lzma --with-lz4 --with-ssl=openssl --with-notify=inotify --with-storages=mdbox,sdbox,maildir,mbox,imapc,pop3c --with-bzlib --with-zlib \
   && make -j3 \
   && make install \

docker-compose.yml

@@ -163,7 +163,7 @@ services:
             - sogo
 
     dovecot-mailcow:
-      image: mailcow/dovecot:1.19
+      image: mailcow/dovecot:1.20
       build: ./data/Dockerfiles/dovecot
       cap_add:
         - NET_BIND_SERVICE