From: Baptiste Daroussin <bapt@FreeBSD.org>
Date: Mon, 8 Jun 2026 21:18:44 +0000 (+0200)
Subject: Fix do_access: add missing NULL check on msg parameter
X-Git-Tag: RELEASE_2_1_0~18
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=efc7b1b5c904dd6df31398287c26dfddd86cf4a4;p=thirdparty%2Fmlmmj.git

Fix do_access: add missing NULL check on msg parameter

The final fallthrough path (no rules matched) called xasprintf(msg, ...)
without checking if msg != NULL, unlike all other xasprintf calls in the
same function. If a caller passes NULL for msg, this would crash in
vasprintf(NULL, ...).
---

diff --git a/src/access.c b/src/access.c
index a084a632..1e9cd3b8 100644
--- a/src/access.c
+++ b/src/access.c
@@ -167,9 +167,10 @@ do_access(strlist *rules, strlist *headers, const char *from, char **msg, char *
 		}
 	}
 
-	xasprintf(msg, "access -"
-			" A mail from \"%s\" didn't match any rules, and"
-			" was denied by default.", from);
+	if (msg != NULL)
+		xasprintf(msg, "access -"
+				" A mail from \"%s\" didn't match any rules, and"
+				" was denied by default.", from);
 	return ACT_DENY;
 }