From: Timo Sirainen <timo.sirainen@open-xchange.com>
Date: Mon, 4 Oct 2021 14:25:05 +0000 (+0300)
Subject: mdbox: Avoid calling container_of() with a NULL pointer
X-Git-Tag: 2.3.18~257
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=79ebaf7b147111abb653334768a20358999b1316;p=thirdparty%2Fdovecot%2Fcore.git

mdbox: Avoid calling container_of() with a NULL pointer
---

diff --git a/src/lib-storage/index/dbox-multi/mdbox-save.c b/src/lib-storage/index/dbox-multi/mdbox-save.c
index 8a614e7c51..c0dcf5b480 100644
--- a/src/lib-storage/index/dbox-multi/mdbox-save.c
+++ b/src/lib-storage/index/dbox-multi/mdbox-save.c
@@ -100,12 +100,13 @@ struct mail_save_context *
 mdbox_save_alloc(struct mailbox_transaction_context *t)
 {
 	struct mdbox_mailbox *mbox = MDBOX_MAILBOX(t->box);
-	struct mdbox_save_context *ctx = MDBOX_SAVECTX(t->save_ctx);
+	struct mdbox_save_context *ctx;
 
 	i_assert((t->flags & MAILBOX_TRANSACTION_FLAG_EXTERNAL) != 0);
 
-	if (ctx != NULL) {
+	if (t->save_ctx != NULL) {
 		/* use the existing allocated structure */
+		ctx = MDBOX_SAVECTX(t->save_ctx);
 		ctx->cur_file = NULL;
 		ctx->ctx.failed = FALSE;
 		ctx->ctx.finished = FALSE;