+From 98f709deac9381721b93d896c27576dbff1f711c Mon Sep 17 00:00:00 2001
+From: Stephan Bosch <stephan.bosch@open-xchange.com>
+Date: Fri, 12 Nov 2021 10:43:16 +0100
+Subject: [PATCH 1/2] lib-storage: mail-duplicate - Fix panic occurring when
+ user has no configured home directory.
+
+Panic was:
+
+Panic: file imem.c: line 65 (i_strconcat): assertion failed: (str1 != NULL)
+---
+ src/lib-storage/mail-duplicate.c | 9 ++++++---
+ 1 file changed, 6 insertions(+), 3 deletions(-)
+
+diff --git a/src/lib-storage/mail-duplicate.c b/src/lib-storage/mail-duplicate.c
+index ff4fa5630b..407fe4aec9 100644
+--- a/src/lib-storage/mail-duplicate.c
++++ b/src/lib-storage/mail-duplicate.c
+@@ -722,14 +722,17 @@ mail_duplicate_db_init(struct mail_user *user, const char *name)
+
+ e_debug(db->event, "Initialize");
+
++ db->user = user;
++
+ if (mail_user_get_home(user, &home) <= 0) {
+ e_error(db->event, "User %s doesn't have home dir set, "
+ "disabling duplicate database", user->username);
++ return db;
+ }
+
+- db->user = user;
+- db->path = home == NULL ? NULL :
+- i_strconcat(home, "/.dovecot.", name, NULL);
++ i_assert(home != NULL);
++
++ db->path = i_strconcat(home, "/.dovecot.", name, NULL);
+ db->dotlock_set = default_mail_duplicate_dotlock_set;
+
+ lock_dir = mail_user_get_volatile_dir(user);
+
+From d36d2c595a12378b597f1fc82cd7b47cbbadb2e1 Mon Sep 17 00:00:00 2001
+From: Stephan Bosch <stephan.bosch@open-xchange.com>
+Date: Fri, 12 Nov 2021 11:16:47 +0100
+Subject: [PATCH 2/2] lib-storage: mail-duplicate - Fix segfault occurring when
+ user has no configured home directory
+
+Occurred only when a duplicate DB transaction was created.
+---
+ src/lib-storage/mail-duplicate.c | 12 +++++++-----
+ 1 file changed, 7 insertions(+), 5 deletions(-)
+
+diff --git a/src/lib-storage/mail-duplicate.c b/src/lib-storage/mail-duplicate.c
+index 407fe4aec9..7a78caa7c7 100644
+--- a/src/lib-storage/mail-duplicate.c
++++ b/src/lib-storage/mail-duplicate.c
+@@ -491,13 +491,15 @@ mail_duplicate_transaction_free(struct mail_duplicate_transaction **_trans)
+ i_assert(trans->db->transaction_count > 0);
+ trans->db->transaction_count--;
+
+- iter = hash_table_iterate_init(trans->hash);
+- while (hash_table_iterate(iter, trans->hash, &d, &d))
+- mail_duplicate_unlock(trans, d);
+- hash_table_iterate_deinit(&iter);
++ if (hash_table_is_created(trans->hash)) {
++ iter = hash_table_iterate_init(trans->hash);
++ while (hash_table_iterate(iter, trans->hash, &d, &d))
++ mail_duplicate_unlock(trans, d);
++ hash_table_iterate_deinit(&iter);
++ hash_table_destroy(&trans->hash);
++ }
+ i_assert(trans->id_lock_count == 0);
+
+- hash_table_destroy(&trans->hash);
+ event_unref(&trans->event);
+ pool_unref(&trans->pool);
+ }