From fba36ac4de82159574480d5dae5756a62f86c17c Mon Sep 17 00:00:00 2001
From: Jamie Gritton <jamie@FreeBSD.org>
Date: Thu, 15 Jul 2010 19:21:33 +0000
Subject: [PATCH] Don't copy and return a potentially unset buffer when
 jail_get fails.

---
 lib/libjail/jail_getid.c | 16 ++++++++++------
 1 file changed, 10 insertions(+), 6 deletions(-)

diff --git a/lib/libjail/jail_getid.c b/lib/libjail/jail_getid.c
index e7601d51b8ba..fa1042407e69 100644
--- a/lib/libjail/jail_getid.c
+++ b/lib/libjail/jail_getid.c
@@ -94,11 +94,15 @@ jail_getname(int jid)
 	jiov[5].iov_len = JAIL_ERRMSGLEN;
 	jail_errmsg[0] = 0;
 	jid = jail_get(jiov, 6, 0);
-	if (jid < 0 && !jail_errmsg[0])
-		snprintf(jail_errmsg, JAIL_ERRMSGLEN, "jail_get: %s",
-		    strerror(errno));
-	name = strdup(namebuf);
-	if (name == NULL)
-		strerror_r(errno, jail_errmsg, JAIL_ERRMSGLEN);
+	if (jid < 0) {
+		if (!jail_errmsg[0])
+			snprintf(jail_errmsg, JAIL_ERRMSGLEN, "jail_get: %s",
+			    strerror(errno));
+		return NULL;
+	} else {
+		name = strdup(namebuf);
+		if (name == NULL)
+			strerror_r(errno, jail_errmsg, JAIL_ERRMSGLEN);
+	}
 	return name;
 }