From: Greg Kroah-Hartman Date: Wed, 18 Dec 2013 19:09:55 +0000 (-0800) Subject: 3.4-stable patches X-Git-Tag: v3.4.75~32 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=c90300d62d7c5f7a9f83492cb497a633ba6195e2;p=thirdparty%2Fkernel%2Fstable-queue.git 3.4-stable patches added patches: selinux-handle-tcp-syn-ack-packets-correctly-in-selinux_ip_output.patch selinux-handle-tcp-syn-ack-packets-correctly-in-selinux_ip_postroute.patch --- diff --git a/queue-3.4/selinux-handle-tcp-syn-ack-packets-correctly-in-selinux_ip_output.patch b/queue-3.4/selinux-handle-tcp-syn-ack-packets-correctly-in-selinux_ip_output.patch new file mode 100644 index 00000000000..0a88cd65de7 --- /dev/null +++ b/queue-3.4/selinux-handle-tcp-syn-ack-packets-correctly-in-selinux_ip_output.patch @@ -0,0 +1,83 @@ +From 47180068276a04ed31d24fe04c673138208b07a9 Mon Sep 17 00:00:00 2001 +From: Paul Moore +Date: Wed, 4 Dec 2013 16:10:45 -0500 +Subject: selinux: handle TCP SYN-ACK packets correctly in selinux_ip_output() + +From: Paul Moore + +commit 47180068276a04ed31d24fe04c673138208b07a9 upstream. + +In selinux_ip_output() we always label packets based on the parent +socket. While this approach works in almost all cases, it doesn't +work in the case of TCP SYN-ACK packets when the correct label is not +the label of the parent socket, but rather the label of the larval +socket represented by the request_sock struct. + +Unfortunately, since the request_sock isn't queued on the parent +socket until *after* the SYN-ACK packet is sent, we can't lookup the +request_sock to determine the correct label for the packet; at this +point in time the best we can do is simply pass/NF_ACCEPT the packet. +It must be said that simply passing the packet without any explicit +labeling action, while far from ideal, is not terrible as the SYN-ACK +packet will inherit any IP option based labeling from the initial +connection request so the label *should* be correct and all our +access controls remain in place so we shouldn't have to worry about +information leaks. + +Reported-by: Janak Desai +Tested-by: Janak Desai +Signed-off-by: Paul Moore +Signed-off-by: Greg Kroah-Hartman + +--- + security/selinux/hooks.c | 25 +++++++++++++++++++++++-- + 1 file changed, 23 insertions(+), 2 deletions(-) + +--- a/security/selinux/hooks.c ++++ b/security/selinux/hooks.c +@@ -52,6 +52,7 @@ + #include + #include /* for local_port_range[] */ + #include /* struct or_callable used in sock_rcv_skb */ ++#include + #include + #include + #include +@@ -4605,6 +4606,7 @@ static unsigned int selinux_ipv6_forward + static unsigned int selinux_ip_output(struct sk_buff *skb, + u16 family) + { ++ struct sock *sk; + u32 sid; + + if (!netlbl_enabled()) +@@ -4613,8 +4615,27 @@ static unsigned int selinux_ip_output(st + /* we do this in the LOCAL_OUT path and not the POST_ROUTING path + * because we want to make sure we apply the necessary labeling + * before IPsec is applied so we can leverage AH protection */ +- if (skb->sk) { +- struct sk_security_struct *sksec = skb->sk->sk_security; ++ sk = skb->sk; ++ if (sk) { ++ struct sk_security_struct *sksec; ++ ++ if (sk->sk_state == TCP_LISTEN) ++ /* if the socket is the listening state then this ++ * packet is a SYN-ACK packet which means it needs to ++ * be labeled based on the connection/request_sock and ++ * not the parent socket. unfortunately, we can't ++ * lookup the request_sock yet as it isn't queued on ++ * the parent socket until after the SYN-ACK is sent. ++ * the "solution" is to simply pass the packet as-is ++ * as any IP option based labeling should be copied ++ * from the initial connection request (in the IP ++ * layer). it is far from ideal, but until we get a ++ * security label in the packet itself this is the ++ * best we can do. */ ++ return NF_ACCEPT; ++ ++ /* standard practice, label using the parent socket */ ++ sksec = sk->sk_security; + sid = sksec->sid; + } else + sid = SECINITSID_KERNEL; diff --git a/queue-3.4/selinux-handle-tcp-syn-ack-packets-correctly-in-selinux_ip_postroute.patch b/queue-3.4/selinux-handle-tcp-syn-ack-packets-correctly-in-selinux_ip_postroute.patch new file mode 100644 index 00000000000..878c6dae8d4 --- /dev/null +++ b/queue-3.4/selinux-handle-tcp-syn-ack-packets-correctly-in-selinux_ip_postroute.patch @@ -0,0 +1,138 @@ +From 446b802437f285de68ffb8d6fac3c44c3cab5b04 Mon Sep 17 00:00:00 2001 +From: Paul Moore +Date: Wed, 4 Dec 2013 16:10:51 -0500 +Subject: selinux: handle TCP SYN-ACK packets correctly in selinux_ip_postroute() + +From: Paul Moore + +commit 446b802437f285de68ffb8d6fac3c44c3cab5b04 upstream. + +In selinux_ip_postroute() we perform access checks based on the +packet's security label. For locally generated traffic we get the +packet's security label from the associated socket; this works in all +cases except for TCP SYN-ACK packets. In the case of SYN-ACK packet's +the correct security label is stored in the connection's request_sock, +not the server's socket. Unfortunately, at the point in time when +selinux_ip_postroute() is called we can't query the request_sock +directly, we need to recreate the label using the same logic that +originally labeled the associated request_sock. + +See the inline comments for more explanation. + +Reported-by: Janak Desai +Tested-by: Janak Desai +Signed-off-by: Paul Moore +Signed-off-by: Greg Kroah-Hartman + +--- + security/selinux/hooks.c | 68 ++++++++++++++++++++++++++++++++++++----------- + 1 file changed, 53 insertions(+), 15 deletions(-) + +--- a/security/selinux/hooks.c ++++ b/security/selinux/hooks.c +@@ -3734,6 +3734,30 @@ static int selinux_skb_peerlbl_sid(struc + return 0; + } + ++/** ++ * selinux_conn_sid - Determine the child socket label for a connection ++ * @sk_sid: the parent socket's SID ++ * @skb_sid: the packet's SID ++ * @conn_sid: the resulting connection SID ++ * ++ * If @skb_sid is valid then the user:role:type information from @sk_sid is ++ * combined with the MLS information from @skb_sid in order to create ++ * @conn_sid. If @skb_sid is not valid then then @conn_sid is simply a copy ++ * of @sk_sid. Returns zero on success, negative values on failure. ++ * ++ */ ++static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid) ++{ ++ int err = 0; ++ ++ if (skb_sid != SECSID_NULL) ++ err = security_sid_mls_copy(sk_sid, skb_sid, conn_sid); ++ else ++ *conn_sid = sk_sid; ++ ++ return err; ++} ++ + /* socket security operations */ + + static int socket_sockcreate_sid(const struct task_security_struct *tsec, +@@ -4355,7 +4379,7 @@ static int selinux_inet_conn_request(str + struct sk_security_struct *sksec = sk->sk_security; + int err; + u16 family = sk->sk_family; +- u32 newsid; ++ u32 connsid; + u32 peersid; + + /* handle mapped IPv4 packets arriving via IPv6 sockets */ +@@ -4365,16 +4389,11 @@ static int selinux_inet_conn_request(str + err = selinux_skb_peerlbl_sid(skb, family, &peersid); + if (err) + return err; +- if (peersid == SECSID_NULL) { +- req->secid = sksec->sid; +- req->peer_secid = SECSID_NULL; +- } else { +- err = security_sid_mls_copy(sksec->sid, peersid, &newsid); +- if (err) +- return err; +- req->secid = newsid; +- req->peer_secid = peersid; +- } ++ err = selinux_conn_sid(sksec->sid, peersid, &connsid); ++ if (err) ++ return err; ++ req->secid = connsid; ++ req->peer_secid = peersid; + + return selinux_netlbl_inet_conn_request(req, family); + } +@@ -4723,12 +4742,12 @@ static unsigned int selinux_ip_postroute + if (!secmark_active && !peerlbl_active) + return NF_ACCEPT; + +- /* if the packet is being forwarded then get the peer label from the +- * packet itself; otherwise check to see if it is from a local +- * application or the kernel, if from an application get the peer label +- * from the sending socket, otherwise use the kernel's sid */ + sk = skb->sk; + if (sk == NULL) { ++ /* Without an associated socket the packet is either coming ++ * from the kernel or it is being forwarded; check the packet ++ * to determine which and if the packet is being forwarded ++ * query the packet directly to determine the security label. */ + if (skb->skb_iif) { + secmark_perm = PACKET__FORWARD_OUT; + if (selinux_skb_peerlbl_sid(skb, family, &peer_sid)) +@@ -4737,7 +4756,26 @@ static unsigned int selinux_ip_postroute + secmark_perm = PACKET__SEND; + peer_sid = SECINITSID_KERNEL; + } ++ } else if (sk->sk_state == TCP_LISTEN) { ++ /* Locally generated packet but the associated socket is in the ++ * listening state which means this is a SYN-ACK packet. In ++ * this particular case the correct security label is assigned ++ * to the connection/request_sock but unfortunately we can't ++ * query the request_sock as it isn't queued on the parent ++ * socket until after the SYN-ACK packet is sent; the only ++ * viable choice is to regenerate the label like we do in ++ * selinux_inet_conn_request(). See also selinux_ip_output() ++ * for similar problems. */ ++ u32 skb_sid; ++ struct sk_security_struct *sksec = sk->sk_security; ++ if (selinux_skb_peerlbl_sid(skb, family, &skb_sid)) ++ return NF_DROP; ++ if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid)) ++ return NF_DROP; ++ secmark_perm = PACKET__SEND; + } else { ++ /* Locally generated packet, fetch the security label from the ++ * associated socket. */ + struct sk_security_struct *sksec = sk->sk_security; + peer_sid = sksec->sid; + secmark_perm = PACKET__SEND; diff --git a/queue-3.4/series b/queue-3.4/series index 5fa9b30687a..6facf1ef473 100644 --- a/queue-3.4/series +++ b/queue-3.4/series @@ -15,3 +15,5 @@ usb-serial-option-blacklist-interface-1-for-huawei-e173s-6.patch usb-option-support-new-huawei-devices.patch input-usbtouchscreen-separate-report-and-transmit-buffer-size-handling.patch drivers-rtc-rtc-at91rm9200.c-correct-alarm-over-day-month-wrap.patch +selinux-handle-tcp-syn-ack-packets-correctly-in-selinux_ip_output.patch +selinux-handle-tcp-syn-ack-packets-correctly-in-selinux_ip_postroute.patch