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net: synack packets can be attached to request sockets

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selinux needs few changes to accommodate fact that SYNACK messages
can be attached to a request socket, lacking sk_security pointer

(Only syncookies are still attached to a TCP_LISTEN socket)

Adds a new sk_listener() helper, and use it in selinux and sch_fq

Fixes: ca6fb06518 ("tcp: attach SYNACK messages to request sockets instead of listener")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported by: kernel test robot <ying.huang@linux.intel.com>
Cc: Paul Moore <paul@paul-moore.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Eric Paris <eparis@parisplace.org>
Acked-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet 2015-10-08 05:01:55 -07:00 committed by David S. Miller
parent 21d11bd6f0
commit e446f9dfe1
3 changed files with 18 additions and 5 deletions
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8
include/net/sock.h
View file

@ -2201,6 +2201,14 @@ static inline bool sk_fullsock(const struct sock *sk)
return (1 << sk->sk_state) & ~(TCPF_TIME_WAIT | TCPF_NEW_SYN_RECV);
}
/* This helper checks if a socket is a LISTEN or NEW_SYN_RECV
* SYNACK messages can be attached to either ones (depending on SYNCOOKIE)
*/
static inline bool sk_listener(const struct sock *sk)
{
return (1 << sk->sk_state) & (TCPF_LISTEN | TCPF_NEW_SYN_RECV);
}
void sock_enable_timestamp(struct sock *sk, int flag);
int sock_get_timestamp(struct sock *, struct timeval __user *);
int sock_get_timestampns(struct sock *, struct timespec __user *);

3
net/sched/sch_fq.c
View file

@ -225,6 +225,7 @@ static struct fq_flow *fq_classify(struct sk_buff *skb, struct fq_sched_data *q)
return &q->internal;
/* SYNACK messages are attached to a TCP_NEW_SYN_RECV request socket
* or a listener (SYNCOOKIE mode)
* 1) request sockets are not full blown,
* they do not contain sk_pacing_rate
* 2) They are not part of a 'flow' yet
@ -232,7 +233,7 @@ static struct fq_flow *fq_classify(struct sk_buff *skb, struct fq_sched_data *q)
* especially if the listener set SO_MAX_PACING_RATE
* 4) We pretend they are orphaned
*/
if (!sk || sk->sk_state == TCP_NEW_SYN_RECV) {
if (!sk || sk_listener(sk)) {
unsigned long hash = skb_get_hash(skb) & q->orphan_mask;
/* By forcing low order bit to 1, we make sure to not

12
security/selinux/hooks.c
View file

@ -4898,7 +4898,7 @@ static unsigned int selinux_ip_output(struct sk_buff *skb,
if (sk) {
struct sk_security_struct *sksec;
if (sk->sk_state == TCP_LISTEN)
if (sk_listener(sk))
/* 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
@ -5005,7 +5005,7 @@ static unsigned int selinux_ip_postroute(struct sk_buff *skb,
* unfortunately, this means more work, but it is only once per
* connection. */
if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL &&
!(sk != NULL && sk->sk_state == TCP_LISTEN))
!(sk && sk_listener(sk)))
return NF_ACCEPT;
#endif
@ -5022,7 +5022,7 @@ static unsigned int selinux_ip_postroute(struct sk_buff *skb,
secmark_perm = PACKET__SEND;
peer_sid = SECINITSID_KERNEL;
}
} else if (sk->sk_state == TCP_LISTEN) {
} else if (sk_listener(sk)) {
/* 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
@ -5033,7 +5033,11 @@ static unsigned int selinux_ip_postroute(struct sk_buff *skb,
* selinux_inet_conn_request(). See also selinux_ip_output()
* for similar problems. */
u32 skb_sid;
struct sk_security_struct *sksec = sk->sk_security;
struct sk_security_struct *sksec;
if (sk->sk_state == TCP_NEW_SYN_RECV)
sk = inet_reqsk(sk)->rsk_listener;
sksec = sk->sk_security;
if (selinux_skb_peerlbl_sid(skb, family, &skb_sid))
return NF_DROP;
/* At this point, if the returned skb peerlbl is SECSID_NULL