From: Aki Tuomi <aki.tuomi@dovecot.fi>
Date: Tue, 25 Oct 2016 07:29:50 +0000 (+0300)
Subject: imap-login: Skip NIL value in ID handler
X-Git-Tag: 2.2.27~308
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=769240367c7c2d4bbc59162da8f6f5a8e92feb6d;p=thirdparty%2Fdovecot%2Fcore.git

imap-login: Skip NIL value in ID handler

NIL value can cause hard crash, depending what
the key is. For x-proxy-ttl, NIL will crash
on any system, x-originating-ip will crash on
some nss versions (e.g. centos 6.7).

Migitating factor here is that the NIL value is only
accepted from trusted network.
---

diff --git a/src/imap-login/imap-login-client.c b/src/imap-login/imap-login-client.c
index b1a6d67a7a..eb89f09144 100644
--- a/src/imap-login/imap-login-client.c
+++ b/src/imap-login/imap-login-client.c
@@ -150,6 +150,9 @@ static void
 client_update_info(struct imap_client *client,
 		   const char *key, const char *value)
 {
+	/* do not try to process NIL value */
+	if (value == NULL)
+		return;
 	if (strcasecmp(key, "x-originating-ip") == 0) {
 		(void)net_addr2ip(value, &client->common.ip);
 	} else if (strcasecmp(key, "x-originating-port") == 0) {