4.18-stable review patch. If anyone has any objections, please let me know.
------------------
From: Piotr Sawicki <p.sawicki2@xxxxxxxxxxxxxxxxxxx>
[ Upstream commit 129a99890936766f4b69b9da7ed88366313a9210 ]
A socket which has sk_family set to PF_INET6 is able to receive not
only IPv6 but also IPv4 traffic (IPv4-mapped IPv6 addresses).
Prior to this patch, the smk_skb_to_addr_ipv6() could have been
called for socket buffers containing IPv4 packets, in result such
traffic was allowed.
Signed-off-by: Piotr Sawicki <p.sawicki2@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Casey Schaufler <casey@xxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
security/smack/smack_lsm.c | 14 +++++++++-----
1 file changed, 9 insertions(+), 5 deletions(-)
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -3924,15 +3924,19 @@ static int smack_socket_sock_rcv_skb(str
struct smack_known *skp = NULL;
int rc = 0;
struct smk_audit_info ad;
+ u16 family = sk->sk_family;
#ifdef CONFIG_AUDIT
struct lsm_network_audit net;
#endif
#if IS_ENABLED(CONFIG_IPV6)
struct sockaddr_in6 sadd;
int proto;
+
+ if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
+ family = PF_INET;
#endif /* CONFIG_IPV6 */
- switch (sk->sk_family) {
+ switch (family) {
case PF_INET:
#ifdef CONFIG_SECURITY_SMACK_NETFILTER
/*
@@ -3950,7 +3954,7 @@ static int smack_socket_sock_rcv_skb(str
*/
netlbl_secattr_init(&secattr);
- rc = netlbl_skbuff_getattr(skb, sk->sk_family, &secattr);
+ rc = netlbl_skbuff_getattr(skb, family, &secattr);
if (rc == 0)
skp = smack_from_secattr(&secattr, ssp);
else
@@ -3963,7 +3967,7 @@ access_check:
#endif
#ifdef CONFIG_AUDIT
smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
- ad.a.u.net->family = sk->sk_family;
+ ad.a.u.net->family = family;
ad.a.u.net->netif = skb->skb_iif;
ipv4_skb_to_auditdata(skb, &ad.a, NULL);
#endif
@@ -3977,7 +3981,7 @@ access_check:
rc = smk_bu_note("IPv4 delivery", skp, ssp->smk_in,
MAY_WRITE, rc);
if (rc != 0)
- netlbl_skbuff_err(skb, sk->sk_family, rc, 0);
+ netlbl_skbuff_err(skb, family, rc, 0);
break;
#if IS_ENABLED(CONFIG_IPV6)
case PF_INET6:
@@ -3993,7 +3997,7 @@ access_check:
skp = smack_net_ambient;
#ifdef CONFIG_AUDIT
smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
- ad.a.u.net->family = sk->sk_family;
+ ad.a.u.net->family = family;
ad.a.u.net->netif = skb->skb_iif;
ipv6_skb_to_auditdata(skb, &ad.a, NULL);
#endif /* CONFIG_AUDIT */
