From: Casey Schaufler <casey@schaufler-ca.com>
Date: Wed, 3 Apr 2019 21:28:38 +0000 (-0700)
Subject: Smack: Fix IPv6 handling of 0 secmark
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=f7450bc6e76860564f3842a41892f9b74313cc23;p=linux.git

Smack: Fix IPv6 handling of 0 secmark

Handle the case where the skb for an IPv6 packet contains
a 0 in the secmark for a packet generated locally. This
can only happen for system packets, so allow the access.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
---

diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index bd45c9139d34c..b9abcdb36a733 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -3907,6 +3907,8 @@ access_check:
 #ifdef SMACK_IPV6_SECMARK_LABELING
 		if (skb && skb->secmark != 0)
 			skp = smack_from_secid(skb->secmark);
+		else if (smk_ipv6_localhost(&sadd))
+			break;
 		else
 			skp = smack_ipv6host_label(&sadd);
 		if (skp == NULL)