sdbox: Avoid calling container_of() with a NULL pointer

diff --git a/src/lib-storage/index/dbox-single/sdbox-save.c b/src/lib-storage/index/dbox-single/sdbox-save.c
index 6349eff1e7a89b600d6b5b5247a0d66b1cb31e8d..03e24ab586846c78faa0fa675090b8c304ba8373 100644 (file)
--- a/src/lib-storage/index/dbox-single/sdbox-save.c
+++ b/src/lib-storage/index/dbox-single/sdbox-save.c
@@ -57,12 +57,13 @@ struct mail_save_context *
 sdbox_save_alloc(struct mailbox_transaction_context *t)
 {
        struct sdbox_mailbox *mbox = SDBOX_MAILBOX(t->box);
-       struct sdbox_save_context *ctx = SDBOX_SAVECTX(t->save_ctx);
+       struct sdbox_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 = SDBOX_SAVECTX(t->save_ctx);
                ctx->cur_file = NULL;
                ctx->ctx.failed = FALSE;
                ctx->ctx.finished = FALSE;