From: Timo Sirainen <tss@iki.fi>
Date: Sun, 22 Sep 2013 03:30:47 +0000 (+0300)
Subject: mbox: Fixed assert-crash due to wrong transaction_count handling.
X-Git-Tag: 2.2.6~8
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=fb100955a1215b4ce3ac89171fcd95c211169f46;p=thirdparty%2Fdovecot%2Fcore.git

mbox: Fixed assert-crash due to wrong transaction_count handling.
This happened only when messages had been expunged by another session just
before saving a new message.
---

diff --git a/src/lib-storage/index/mbox/mbox-storage.c b/src/lib-storage/index/mbox/mbox-storage.c
index 0d4195182f..4b6fef54a9 100644
--- a/src/lib-storage/index/mbox/mbox-storage.c
+++ b/src/lib-storage/index/mbox/mbox-storage.c
@@ -737,7 +737,8 @@ mbox_transaction_unlock(struct mailbox *box, unsigned int lock_id1,
 	if (lock_id2 != 0)
 		mbox_unlock(mbox, lock_id2);
 	if (mbox->mbox_global_lock_id == 0) {
-		i_assert(mbox->box.transaction_count > 0 ||
+		i_assert(mbox->box.transaction_count > 0);
+		i_assert(mbox->box.transaction_count > 1 ||
 			 mbox->external_transactions > 0 ||
 			 mbox->mbox_lock_type == F_UNLCK);
 	} else {
diff --git a/src/lib-storage/mail-storage.c b/src/lib-storage/mail-storage.c
index 415b00c6f3..4e753f45c3 100644
--- a/src/lib-storage/mail-storage.c
+++ b/src/lib-storage/mail-storage.c
@@ -1836,15 +1836,15 @@ int mailbox_transaction_commit_get_changes(
 	struct mail_transaction_commit_changes *changes_r)
 {
 	struct mailbox_transaction_context *t = *_t;
+	struct mailbox *box = t->box;
 	unsigned int save_count = t->save_count;
 	int ret;
 
-	t->box->transaction_count--;
 	changes_r->pool = NULL;
 
 	*_t = NULL;
 	T_BEGIN {
-		ret = t->box->v.transaction_commit(t, changes_r);
+		ret = box->v.transaction_commit(t, changes_r);
 	} T_END;
 	/* either all the saved messages get UIDs or none, because a) we
 	   failed, b) MAILBOX_TRANSACTION_FLAG_ASSIGN_UIDS not set,
@@ -1852,6 +1852,11 @@ int mailbox_transaction_commit_get_changes(
 	i_assert(ret < 0 ||
 		 seq_range_count(&changes_r->saved_uids) == save_count ||
 		 array_count(&changes_r->saved_uids) == 0);
+	/* decrease the transaction count only after transaction_commit().
+	   that way if it creates and destroys transactions internally, we
+	   don't see transaction_count=0 until the parent transaction is fully
+	   finished */
+	box->transaction_count--;
 	if (ret < 0 && changes_r->pool != NULL)
 		pool_unref(&changes_r->pool);
 	return ret;
@@ -1860,11 +1865,11 @@ int mailbox_transaction_commit_get_changes(
 void mailbox_transaction_rollback(struct mailbox_transaction_context **_t)
 {
 	struct mailbox_transaction_context *t = *_t;
-
-	t->box->transaction_count--;
+	struct mailbox *box = t->box;
 
 	*_t = NULL;
-	t->box->v.transaction_rollback(t);
+	box->v.transaction_rollback(t);
+	box->transaction_count--;
 }
 
 unsigned int mailbox_transaction_get_count(const struct mailbox *box)