From ac0b04627269ff16c3c7ab854a65fe6780c6e3e5 Mon Sep 17 00:00:00 2001
From: Sridhar Samudrala <sri@us.ibm.com>
Date: Tue, 22 Aug 2006 00:15:33 -0700
Subject: [SCTP]: Extend /proc/net/sctp/snmp to provide more statistics.
This patch adds more statistics info under /proc/net/sctp/snmp
that should be useful for debugging. The additional events that
are counted now include timer expirations, retransmits, packet
and data chunk discards.
The Data chunk discards include all the cases where a data chunk
is discarded including high tsn, bad stream, dup tsn and the most
useful one(out of receive buffer/rwnd).
Also moved the SCTP MIB data structures from the generic include
directories to include/sctp/sctp.h.
Signed-off-by: Sridhar Samudrala <sri@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
net/sctp/input.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
(limited to 'net/sctp/input.c')
diff --git a/net/sctp/input.c b/net/sctp/input.c
index 42b66e74bbb..8a34d95602c 100644
--- a/net/sctp/input.c
+++ b/net/sctp/input.c
@@ -255,10 +255,13 @@ int sctp_rcv(struct sk_buff *skb)
*/
sctp_bh_lock_sock(sk);
- if (sock_owned_by_user(sk))
+ if (sock_owned_by_user(sk)) {
+ SCTP_INC_STATS_BH(SCTP_MIB_IN_PKT_BACKLOG);
sctp_add_backlog(sk, skb);
- else
+ } else {
+ SCTP_INC_STATS_BH(SCTP_MIB_IN_PKT_SOFTIRQ);
sctp_inq_push(&chunk->rcvr->inqueue, chunk);
+ }
sctp_bh_unlock_sock(sk);
@@ -271,6 +274,7 @@ int sctp_rcv(struct sk_buff *skb)
return 0;
discard_it:
+ SCTP_INC_STATS_BH(SCTP_MIB_IN_PKT_DISCARDS);
kfree_skb(skb);
return 0;
--
cgit v1.2.3-70-g09d2
From fda9ef5d679b07c9d9097aaf6ef7f069d794a8f9 Mon Sep 17 00:00:00 2001
From: Dmitry Mishin <dim@openvz.org>
Date: Thu, 31 Aug 2006 15:28:39 -0700
Subject: [NET]: Fix sk->sk_filter field access
Function sk_filter() is called from tcp_v{4,6}_rcv() functions with arg
needlock = 0, while socket is not locked at that moment. In order to avoid
this and similar issues in the future, use rcu for sk->sk_filter field read
protection.
Signed-off-by: Dmitry Mishin <dim@openvz.org>
Signed-off-by: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Signed-off-by: Kirill Korotaev <dev@openvz.org>
---
include/linux/filter.h | 13 +++++++------
include/net/sock.h | 34 +++++++++++++++++-----------------
net/core/filter.c | 8 ++++----
net/core/sock.c | 22 +++++++++-------------
net/dccp/ipv6.c | 2 +-
net/decnet/dn_nsp_in.c | 2 +-
net/ipv4/tcp_ipv4.c | 2 +-
net/ipv6/tcp_ipv6.c | 4 ++--
net/packet/af_packet.c | 43 ++++++++++++++++++-------------------------
net/sctp/input.c | 2 +-
10 files changed, 61 insertions(+), 71 deletions(-)
(limited to 'net/sctp/input.c')
diff --git a/include/linux/filter.h b/include/linux/filter.h
index c6cb8f09508..91b2e3b9251 100644
--- a/include/linux/filter.h
+++ b/include/linux/filter.h
@@ -25,10 +25,10 @@
struct sock_filter /* Filter block */
{
- __u16 code; /* Actual filter code */
- __u8 jt; /* Jump true */
- __u8 jf; /* Jump false */
- __u32 k; /* Generic multiuse field */
+ __u16 code; /* Actual filter code */
+ __u8 jt; /* Jump true */
+ __u8 jf; /* Jump false */
+ __u32 k; /* Generic multiuse field */
};
struct sock_fprog /* Required for SO_ATTACH_FILTER. */
@@ -41,8 +41,9 @@ struct sock_fprog /* Required for SO_ATTACH_FILTER. */
struct sk_filter
{
atomic_t refcnt;
- unsigned int len; /* Number of filter blocks */
- struct sock_filter insns[0];
+ unsigned int len; /* Number of filter blocks */
+ struct rcu_head rcu;
+ struct sock_filter insns[0];
};
static inline unsigned int sk_filter_len(struct sk_filter *fp)
diff --git a/include/net/sock.h b/include/net/sock.h
index 337ebec84c7..edd4d73ce7f 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -862,30 +862,24 @@ extern void sock_init_data(struct socket *sock, struct sock *sk);
*
*/
-static inline int sk_filter(struct sock *sk, struct sk_buff *skb, int needlock)
+static inline int sk_filter(struct sock *sk, struct sk_buff *skb)
{
int err;
+ struct sk_filter *filter;
err = security_sock_rcv_skb(sk, skb);
if (err)
return err;
- if (sk->sk_filter) {
- struct sk_filter *filter;
-
- if (needlock)
- bh_lock_sock(sk);
-
- filter = sk->sk_filter;
- if (filter) {
- unsigned int pkt_len = sk_run_filter(skb, filter->insns,
- filter->len);
- err = pkt_len ? pskb_trim(skb, pkt_len) : -EPERM;
- }
-
- if (needlock)
- bh_unlock_sock(sk);
+ rcu_read_lock_bh();
+ filter = sk->sk_filter;
+ if (filter) {
+ unsigned int pkt_len = sk_run_filter(skb, filter->insns,
+ filter->len);
+ err = pkt_len ? pskb_trim(skb, pkt_len) : -EPERM;
}
+ rcu_read_unlock_bh();
+
return err;
}
@@ -897,6 +891,12 @@ static inline int sk_filter(struct sock *sk, struct sk_buff *skb, int needlock)
* Remove a filter from a socket and release its resources.
*/
+static inline void sk_filter_rcu_free(struct rcu_head *rcu)
+{
+ struct sk_filter *fp = container_of(rcu, struct sk_filter, rcu);
+ kfree(fp);
+}
+
static inline void sk_filter_release(struct sock *sk, struct sk_filter *fp)
{
unsigned int size = sk_filter_len(fp);
@@ -904,7 +904,7 @@ static inline void sk_filter_release(struct sock *sk, struct sk_filter *fp)
atomic_sub(size, &sk->sk_omem_alloc);
if (atomic_dec_and_test(&fp->refcnt))
- kfree(fp);
+ call_rcu_bh(&fp->rcu, sk_filter_rcu_free);
}
static inline void sk_filter_charge(struct sock *sk, struct sk_filter *fp)
diff --git a/net/core/filter.c b/net/core/filter.c
index 5b4486a60cf..6732782a5a4 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -422,10 +422,10 @@ int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk)
if (!err) {
struct sk_filter *old_fp;
- spin_lock_bh(&sk->sk_lock.slock);
- old_fp = sk->sk_filter;
- sk->sk_filter = fp;
- spin_unlock_bh(&sk->sk_lock.slock);
+ rcu_read_lock_bh();
+ old_fp = rcu_dereference(sk->sk_filter);
+ rcu_assign_pointer(sk->sk_filter, fp);
+ rcu_read_unlock_bh();
fp = old_fp;
}
diff --git a/net/core/sock.c b/net/core/sock.c
index cfaf09039b0..b77e155cbe6 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -247,11 +247,7 @@ int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
goto out;
}
- /* It would be deadlock, if sock_queue_rcv_skb is used
- with socket lock! We assume that users of this
- function are lock free.
- */
- err = sk_filter(sk, skb, 1);
+ err = sk_filter(sk, skb);
if (err)
goto out;
@@ -278,7 +274,7 @@ int sk_receive_skb(struct sock *sk, struct sk_buff *skb)
{
int rc = NET_RX_SUCCESS;
- if (sk_filter(sk, skb, 0))
+ if (sk_filter(sk, skb))
goto discard_and_relse;
skb->dev = NULL;
@@ -606,15 +602,15 @@ set_rcvbuf:
break;
case SO_DETACH_FILTER:
- spin_lock_bh(&sk->sk_lock.slock);
- filter = sk->sk_filter;
+ rcu_read_lock_bh();
+ filter = rcu_dereference(sk->sk_filter);
if (filter) {
- sk->sk_filter = NULL;
- spin_unlock_bh(&sk->sk_lock.slock);
+ rcu_assign_pointer(sk->sk_filter, NULL);
sk_filter_release(sk, filter);
+ rcu_read_unlock_bh();
break;
}
- spin_unlock_bh(&sk->sk_lock.slock);
+ rcu_read_unlock_bh();
ret = -ENONET;
break;
@@ -884,10 +880,10 @@ void sk_free(struct sock *sk)
if (sk->sk_destruct)
sk->sk_destruct(sk);
- filter = sk->sk_filter;
+ filter = rcu_dereference(sk->sk_filter);
if (filter) {
sk_filter_release(sk, filter);
- sk->sk_filter = NULL;
+ rcu_assign_pointer(sk->sk_filter, NULL);
}
sock_disable_timestamp(sk);
diff --git a/net/dccp/ipv6.c b/net/dccp/ipv6.c
index f9c5e12d703..7a47399cf31 100644
--- a/net/dccp/ipv6.c
+++ b/net/dccp/ipv6.c
@@ -970,7 +970,7 @@ static int dccp_v6_do_rcv(struct sock *sk, struct sk_buff *skb)
if (skb->protocol == htons(ETH_P_IP))
return dccp_v4_do_rcv(sk, skb);
- if (sk_filter(sk, skb, 0))
+ if (sk_filter(sk, skb))
goto discard;
/*
diff --git a/net/decnet/dn_nsp_in.c b/net/decnet/dn_nsp_in.c
index 86f7f3b28e7..72ecc6e62ec 100644
--- a/net/decnet/dn_nsp_in.c
+++ b/net/decnet/dn_nsp_in.c
@@ -586,7 +586,7 @@ static __inline__ int dn_queue_skb(struct sock *sk, struct sk_buff *skb, int sig
goto out;
}
- err = sk_filter(sk, skb, 0);
+ err = sk_filter(sk, skb);
if (err)
goto out;
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 23b46e36b14..39b17985608 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -1104,7 +1104,7 @@ process:
goto discard_and_relse;
nf_reset(skb);
- if (sk_filter(sk, skb, 0))
+ if (sk_filter(sk, skb))
goto discard_and_relse;
skb->dev = NULL;
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 2b18918f301..2546fc9f0a7 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -1075,7 +1075,7 @@ static int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb)
if (skb->protocol == htons(ETH_P_IP))
return tcp_v4_do_rcv(sk, skb);
- if (sk_filter(sk, skb, 0))
+ if (sk_filter(sk, skb))
goto discard;
/*
@@ -1232,7 +1232,7 @@ process:
if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
goto discard_and_relse;
- if (sk_filter(sk, skb, 0))
+ if (sk_filter(sk, skb))
goto discard_and_relse;
skb->dev = NULL;
diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c
index 300215bdbf4..f4ccb90e673 100644
--- a/net/packet/af_packet.c
+++ b/net/packet/af_packet.c
@@ -427,21 +427,24 @@ out_unlock:
}
#endif
-static inline unsigned run_filter(struct sk_buff *skb, struct sock *sk, unsigned res)
+static inline int run_filter(struct sk_buff *skb, struct sock *sk,
+ unsigned *snaplen)
{
struct sk_filter *filter;
+ int err = 0;
- bh_lock_sock(sk);
- filter = sk->sk_filter;
- /*
- * Our caller already checked that filter != NULL but we need to
- * verify that under bh_lock_sock() to be safe
- */
- if (likely(filter != NULL))
- res = sk_run_filter(skb, filter->insns, filter->len);
- bh_unlock_sock(sk);
+ rcu_read_lock_bh();
+ filter = rcu_dereference(sk->sk_filter);
+ if (filter != NULL) {
+ err = sk_run_filter(skb, filter->insns, filter->len);
+ if (!err)
+ err = -EPERM;
+ else if (*snaplen > err)
+ *snaplen = err;
+ }
+ rcu_read_unlock_bh();
- return res;
+ return err;
}
/*
@@ -491,13 +494,8 @@ static int packet_rcv(struct sk_buff *skb, struct net_device *dev, struct packet
snaplen = skb->len;
- if (sk->sk_filter) {
- unsigned res = run_filter(skb, sk, snaplen);
- if (res == 0)
- goto drop_n_restore;
- if (snaplen > res)
- snaplen = res;
- }
+ if (run_filter(skb, sk, &snaplen) < 0)
+ goto drop_n_restore;
if (atomic_read(&sk->sk_rmem_alloc) + skb->truesize >=
(unsigned)sk->sk_rcvbuf)
@@ -593,13 +591,8 @@ static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev, struct packe
snaplen = skb->len;
- if (sk->sk_filter) {
- unsigned res = run_filter(skb, sk, snaplen);
- if (res == 0)
- goto drop_n_restore;
- if (snaplen > res)
- snaplen = res;
- }
+ if (run_filter(skb, sk, &snaplen) < 0)
+ goto drop_n_restore;
if (sk->sk_type == SOCK_DGRAM) {
macoff = netoff = TPACKET_ALIGN(TPACKET_HDRLEN) + 16;
diff --git a/net/sctp/input.c b/net/sctp/input.c
index 8a34d95602c..03f65de75d8 100644
--- a/net/sctp/input.c
+++ b/net/sctp/input.c
@@ -228,7 +228,7 @@ int sctp_rcv(struct sk_buff *skb)
goto discard_release;
nf_reset(skb);
- if (sk_filter(sk, skb, 1))
+ if (sk_filter(sk, skb))
goto discard_release;
/* Create an SCTP packet structure. */
--
cgit v1.2.3-70-g09d2