[patch v3 01/11] netlink: add reference of module in netlink_dump_start

[patch v3 01/11] netlink: add reference of module in netlink_dump_start

[Gao feng]

I get a panic when I use ss -a and rmmod inet_diag at the
same time.

it's because netlink_dump use inet_diag_dump witch function
belongs to module inet_diag.

I search the codes and find many modules have the same problem.
We need add reference of the module witch the cb->dump belongs
to.

Thanks for all help from Stephen,Jan,Eric,Steffen and Pablo.

Change From v2:

delete netlink_dump_done,and call module_put in netlink_dump
and netlink_sock_destruct.

Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
---
 include/linux/netlink.h  |    5 ++++-
 net/netlink/af_netlink.c |   21 +++++++++++++++++----
 2 files changed, 21 insertions(+), 5 deletions(-)

diff --git a/include/linux/netlink.h b/include/linux/netlink.h
index f80c56a..bf4e501 100644
--- a/include/linux/netlink.h
+++ b/include/linux/netlink.h
@@ -245,6 +245,8 @@ struct netlink_callback {
 					struct netlink_callback *cb);
 	int			(*done)(struct netlink_callback *cb);
 	void			*data;
+	/* the module that dump function belong to */
+	struct module		*module;
 	u16			family;
 	u16			min_dump_alloc;
 	unsigned int		prev_seq, seq;
@@ -262,8 +264,9 @@ __nlmsg_put(struct sk_buff *skb, u32 portid, u32 seq, int type, int len, int fla
 
 struct netlink_dump_control {
 	int (*dump)(struct sk_buff *skb, struct netlink_callback *);
-	int (*done)(struct netlink_callback*);
+	int (*done)(struct netlink_callback *);
 	void *data;
+	struct module *module;
 	u16 min_dump_alloc;
 };
 
diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c
index 0f2e3ad..0905dfb 100644
--- a/net/netlink/af_netlink.c
+++ b/net/netlink/af_netlink.c
@@ -169,6 +169,7 @@ static void netlink_sock_destruct(struct sock *sk)
 	if (nlk->cb) {
 		if (nlk->cb->done)
 			nlk->cb->done(nlk->cb);
+		module_put(nlk->cb->module);
 		netlink_destroy_callback(nlk->cb);
 	}
 
@@ -1755,6 +1756,8 @@ static int netlink_dump(struct sock *sk)
 
 	if (cb->done)
 		cb->done(cb);
+
+	module_put(cb->module);
 	nlk->cb = NULL;
 	mutex_unlock(nlk->cb_mutex);
 
@@ -1784,6 +1787,7 @@ int netlink_dump_start(struct sock *ssk, struct sk_buff *skb,
 	cb->done = control->done;
 	cb->nlh = nlh;
 	cb->data = control->data;
+	cb->module = control->module;
 	cb->min_dump_alloc = control->min_dump_alloc;
 	atomic_inc(&skb->users);
 	cb->skb = skb;
@@ -1794,19 +1798,28 @@ int netlink_dump_start(struct sock *ssk, struct sk_buff *skb,
 		return -ECONNREFUSED;
 	}
 	nlk = nlk_sk(sk);
-	/* A dump is in progress... */
+
 	mutex_lock(nlk->cb_mutex);
+	/* A dump is in progress... */
 	if (nlk->cb) {
 		mutex_unlock(nlk->cb_mutex);
 		netlink_destroy_callback(cb);
-		sock_put(sk);
-		return -EBUSY;
+		ret = -EBUSY;
+		goto out;
 	}
+	/* add reference of module witch cb->dump belong to */
+	if (!try_module_get(cb->module)) {
+		mutex_unlock(nlk->cb_mutex);
+		netlink_destroy_callback(cb);
+		ret = -EPROTONOSUPPORT;
+		goto out;
+	}
+
 	nlk->cb = cb;
 	mutex_unlock(nlk->cb_mutex);
 
 	ret = netlink_dump(sk);
-
+out:
 	sock_put(sk);
 
 	if (ret)
-- 
1.7.7.6

[patch v3 02/11] inet_diag: pass inet_diag module to netlink_dump_start

[Gao feng]

set netlink_dump_control.module to avoid panic.

Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
---
 net/ipv4/inet_diag.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)

diff --git a/net/ipv4/inet_diag.c b/net/ipv4/inet_diag.c
index 535584c..5ffd7bc 100644
--- a/net/ipv4/inet_diag.c
+++ b/net/ipv4/inet_diag.c
@@ -981,6 +981,7 @@ static int inet_diag_rcv_msg_compat(struct sk_buff *skb, struct nlmsghdr *nlh)
 		{
 			struct netlink_dump_control c = {
 				.dump = inet_diag_dump_compat,
+				.module = THIS_MODULE,
 			};
 			return netlink_dump_start(net->diag_nlsk, skb, nlh, &c);
 		}
@@ -1010,6 +1011,7 @@ static int inet_diag_handler_dump(struct sk_buff *skb, struct nlmsghdr *h)
 		{
 			struct netlink_dump_control c = {
 				.dump = inet_diag_dump,
+				.module = THIS_MODULE,
 			};
 			return netlink_dump_start(net->diag_nlsk, skb, h, &c);
 		}
-- 
1.7.7.6

[patch v3 03/11] unix_diag: pass unix_diag module to netlink_dump_start

[Gao feng]

set netlink_dump_control.module to avoid panic.

Signed-off-by: Gao feng <gaofeng-BthXqXjhjHXQFUHtdCDX3A@public.gmane.org>
---
 net/unix/diag.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/net/unix/diag.c b/net/unix/diag.c
index 06748f1..e1cd31f 100644
--- a/net/unix/diag.c
+++ b/net/unix/diag.c
@@ -299,6 +299,7 @@ static int unix_diag_handler_dump(struct sk_buff *skb, struct nlmsghdr *h)
 	if (h->nlmsg_flags & NLM_F_DUMP) {
 		struct netlink_dump_control c = {
 			.dump = unix_diag_dump,
+			.module = THIS_MODULE,
 		};
 		return netlink_dump_start(net->diag_nlsk, skb, h, &c);
 	} else
-- 
1.7.7.6

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[patch v3 04/11] nf_conntrack_netlink: pass nf_conntrack_netlink module to netlink_dump_start

[Gao feng]

set netlink_dump_control.module to avoid panic.

Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
---
 net/netfilter/nf_conntrack_netlink.c |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)

diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c
index 7bbfb3d..20af287 100644
--- a/net/netfilter/nf_conntrack_netlink.c
+++ b/net/netfilter/nf_conntrack_netlink.c
@@ -1022,6 +1022,7 @@ ctnetlink_get_conntrack(struct sock *ctnl, struct sk_buff *skb,
 		struct netlink_dump_control c = {
 			.dump = ctnetlink_dump_table,
 			.done = ctnetlink_done,
+			.module = THIS_MODULE,
 		};
 #ifdef CONFIG_NF_CONNTRACK_MARK
 		if (cda[CTA_MARK] && cda[CTA_MARK_MASK]) {
@@ -1723,6 +1724,7 @@ ctnetlink_stat_ct_cpu(struct sock *ctnl, struct sk_buff *skb,
 	if (nlh->nlmsg_flags & NLM_F_DUMP) {
 		struct netlink_dump_control c = {
 			.dump = ctnetlink_ct_stat_cpu_dump,
+			.module = THIS_MODULE,
 		};
 		return netlink_dump_start(ctnl, skb, nlh, &c);
 	}
@@ -2242,6 +2244,7 @@ ctnetlink_get_expect(struct sock *ctnl, struct sk_buff *skb,
 		struct netlink_dump_control c = {
 			.dump = ctnetlink_exp_dump_table,
 			.done = ctnetlink_exp_done,
+			.module = THIS_MODULE,
 		};
 		return netlink_dump_start(ctnl, skb, nlh, &c);
 	}
@@ -2680,6 +2683,7 @@ ctnetlink_stat_exp_cpu(struct sock *ctnl, struct sk_buff *skb,
 	if (nlh->nlmsg_flags & NLM_F_DUMP) {
 		struct netlink_dump_control c = {
 			.dump = ctnetlink_exp_stat_cpu_dump,
+			.module = THIS_MODULE,
 		};
 		return netlink_dump_start(ctnl, skb, nlh, &c);
 	}
-- 
1.7.7.6

[patch v3 05/11] nfnetlink_acct: pass nfnetlink_acct module to netlink_dump_start

[Gao feng]

set netlink_dump_control.module to avoid panic.

Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
---
 net/netfilter/nfnetlink_acct.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/net/netfilter/nfnetlink_acct.c b/net/netfilter/nfnetlink_acct.c
index 589d686..8acf8b8 100644
--- a/net/netfilter/nfnetlink_acct.c
+++ b/net/netfilter/nfnetlink_acct.c
@@ -175,6 +175,7 @@ nfnl_acct_get(struct sock *nfnl, struct sk_buff *skb,
 	if (nlh->nlmsg_flags & NLM_F_DUMP) {
 		struct netlink_dump_control c = {
 			.dump = nfnl_acct_dump,
+			.module = THIS_MODULE,
 		};
 		return netlink_dump_start(nfnl, skb, nlh, &c);
 	}
-- 
1.7.7.6

[patch v3 06/11] nfnetlink_cthelper: pass nfnetlink_cthelper module to netlink_dump_start

[Gao feng]

set netlink_dump_control.module to avoid panic.

Signed-off-by: Gao feng <gaofeng-BthXqXjhjHXQFUHtdCDX3A@public.gmane.org>
---
 net/netfilter/nfnetlink_cthelper.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/net/netfilter/nfnetlink_cthelper.c b/net/netfilter/nfnetlink_cthelper.c
index 945950a..2bcd2d8 100644
--- a/net/netfilter/nfnetlink_cthelper.c
+++ b/net/netfilter/nfnetlink_cthelper.c
@@ -504,6 +504,7 @@ nfnl_cthelper_get(struct sock *nfnl, struct sk_buff *skb,
 	if (nlh->nlmsg_flags & NLM_F_DUMP) {
 		struct netlink_dump_control c = {
 			.dump = nfnl_cthelper_dump_table,
+			.module = THIS_MODULE,
 		};
 		return netlink_dump_start(nfnl, skb, nlh, &c);
 	}
-- 
1.7.7.6

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[patch v3 07/11] nfnetlink_cttimeout: pass nfnetlink_cttimeout module to netlink_dump_start

[Gao feng]

set netlink_dump_control.module to avoid panic.

Signed-off-by: Gao feng <gaofeng-BthXqXjhjHXQFUHtdCDX3A@public.gmane.org>
---
 net/netfilter/nfnetlink_cttimeout.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/net/netfilter/nfnetlink_cttimeout.c b/net/netfilter/nfnetlink_cttimeout.c
index 8847b4d..e0ab57c 100644
--- a/net/netfilter/nfnetlink_cttimeout.c
+++ b/net/netfilter/nfnetlink_cttimeout.c
@@ -248,6 +248,7 @@ cttimeout_get_timeout(struct sock *ctnl, struct sk_buff *skb,
 	if (nlh->nlmsg_flags & NLM_F_DUMP) {
 		struct netlink_dump_control c = {
 			.dump = ctnl_timeout_dump,
+			.module = THIS_MODULE,
 		};
 		return netlink_dump_start(ctnl, skb, nlh, &c);
 	}
-- 
1.7.7.6

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[patch v3 08/11] crypto: pass crypto_user module to netlink_dump_start

[Gao feng]

set netlink_dump_control.done to avoid panic.

Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
---
 crypto/crypto_user.c |    5 ++++-
 1 files changed, 4 insertions(+), 1 deletions(-)

diff --git a/crypto/crypto_user.c b/crypto/crypto_user.c
index 6bba414..f08297b 100644
--- a/crypto/crypto_user.c
+++ b/crypto/crypto_user.c
@@ -430,13 +430,15 @@ static struct crypto_link {
 	int (*doit)(struct sk_buff *, struct nlmsghdr *, struct nlattr **);
 	int (*dump)(struct sk_buff *, struct netlink_callback *);
 	int (*done)(struct netlink_callback *);
+	struct module *module;
 } crypto_dispatch[CRYPTO_NR_MSGTYPES] = {
 	[CRYPTO_MSG_NEWALG	- CRYPTO_MSG_BASE] = { .doit = crypto_add_alg},
 	[CRYPTO_MSG_DELALG	- CRYPTO_MSG_BASE] = { .doit = crypto_del_alg},
 	[CRYPTO_MSG_UPDATEALG	- CRYPTO_MSG_BASE] = { .doit = crypto_update_alg},
 	[CRYPTO_MSG_GETALG	- CRYPTO_MSG_BASE] = { .doit = crypto_report,
 						       .dump = crypto_dump_report,
-						       .done = crypto_dump_report_done},
+						       .done = crypto_dump_report_done,
+						       .module = THIS_MODULE},
 };
 
 static int crypto_user_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
@@ -471,6 +473,7 @@ static int crypto_user_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
 				.dump = link->dump,
 				.done = link->done,
 				.min_dump_alloc = dump_alloc,
+				.module = link->module,
 			};
 			return netlink_dump_start(crypto_nlsk, skb, nlh, &c);
 		}
-- 
1.7.7.6

[patch v3 09/11] xfrm: pass xfrm_user module to netlink_dump_start

[Gao feng]

set netlink_dump_control.module to avoid panic.

Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
---
 net/xfrm/xfrm_user.c |    8 ++++++--
 1 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c
index 421f984..3d909f7 100644
--- a/net/xfrm/xfrm_user.c
+++ b/net/xfrm/xfrm_user.c
@@ -2308,17 +2308,20 @@ static struct xfrm_link {
 	int (*doit)(struct sk_buff *, struct nlmsghdr *, struct nlattr **);
 	int (*dump)(struct sk_buff *, struct netlink_callback *);
 	int (*done)(struct netlink_callback *);
+	struct module *module;
 } xfrm_dispatch[XFRM_NR_MSGTYPES] = {
 	[XFRM_MSG_NEWSA       - XFRM_MSG_BASE] = { .doit = xfrm_add_sa        },
 	[XFRM_MSG_DELSA       - XFRM_MSG_BASE] = { .doit = xfrm_del_sa        },
 	[XFRM_MSG_GETSA       - XFRM_MSG_BASE] = { .doit = xfrm_get_sa,
 						   .dump = xfrm_dump_sa,
-						   .done = xfrm_dump_sa_done  },
+						   .done = xfrm_dump_sa_done,
+						   .module = THIS_MODULE      },
 	[XFRM_MSG_NEWPOLICY   - XFRM_MSG_BASE] = { .doit = xfrm_add_policy    },
 	[XFRM_MSG_DELPOLICY   - XFRM_MSG_BASE] = { .doit = xfrm_get_policy    },
 	[XFRM_MSG_GETPOLICY   - XFRM_MSG_BASE] = { .doit = xfrm_get_policy,
 						   .dump = xfrm_dump_policy,
-						   .done = xfrm_dump_policy_done },
+						   .done = xfrm_dump_policy_done,
+						   .module = THIS_MODULE      },
 	[XFRM_MSG_ALLOCSPI    - XFRM_MSG_BASE] = { .doit = xfrm_alloc_userspi },
 	[XFRM_MSG_ACQUIRE     - XFRM_MSG_BASE] = { .doit = xfrm_add_acquire   },
 	[XFRM_MSG_EXPIRE      - XFRM_MSG_BASE] = { .doit = xfrm_add_sa_expire },
@@ -2362,6 +2365,7 @@ static int xfrm_user_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
 			struct netlink_dump_control c = {
 				.dump = link->dump,
 				.done = link->done,
+				.module = link->module,
 			};
 			return netlink_dump_start(net->xfrm.nlsk, skb, nlh, &c);
 		}
-- 
1.7.7.6

[patch v3 10/11] ipset: pass ipset module to netlink_dump_start

[Gao feng]

set netlink_dump_control.module to avoid panic.

Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Cc: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
---
 net/netfilter/ipset/ip_set_core.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/net/netfilter/ipset/ip_set_core.c b/net/netfilter/ipset/ip_set_core.c
index 778465f..6f2b55c 100644
--- a/net/netfilter/ipset/ip_set_core.c
+++ b/net/netfilter/ipset/ip_set_core.c
@@ -1185,6 +1185,7 @@ ip_set_dump(struct sock *ctnl, struct sk_buff *skb,
 		struct netlink_dump_control c = {
 			.dump = ip_set_dump_start,
 			.done = ip_set_dump_done,
+			.module = THIS_MODULE,
 		};
 		return netlink_dump_start(ctnl, skb, nlh, &c);
 	}
-- 
1.7.7.6

[patch v3 11/11] infiniband: pass rdma_cm module to netlink_dump_start

[Gao feng]

set netlink_dump_control.module to avoid panic.

Signed-off-by: Gao feng <gaofeng-BthXqXjhjHXQFUHtdCDX3A@public.gmane.org>
Cc: Roland Dreier <roland-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
Cc: Sean Hefty <sean.hefty-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
---
 drivers/infiniband/core/cma.c     |    3 ++-
 drivers/infiniband/core/netlink.c |    1 +
 include/rdma/rdma_netlink.h       |    1 +
 3 files changed, 4 insertions(+), 1 deletions(-)

diff --git a/drivers/infiniband/core/cma.c b/drivers/infiniband/core/cma.c
index 26b3760..4fff27a 100644
--- a/drivers/infiniband/core/cma.c
+++ b/drivers/infiniband/core/cma.c
@@ -3498,7 +3498,8 @@ out:
 }
 
 static const struct ibnl_client_cbs cma_cb_table[] = {
-	[RDMA_NL_RDMA_CM_ID_STATS] = { .dump = cma_get_id_stats },
+	[RDMA_NL_RDMA_CM_ID_STATS] = { .dump = cma_get_id_stats,
+				       .module = THIS_MODULE },
 };
 
 static int __init cma_init(void)
diff --git a/drivers/infiniband/core/netlink.c b/drivers/infiniband/core/netlink.c
index fe10a94..da06abd 100644
--- a/drivers/infiniband/core/netlink.c
+++ b/drivers/infiniband/core/netlink.c
@@ -154,6 +154,7 @@ static int ibnl_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
 			{
 				struct netlink_dump_control c = {
 					.dump = client->cb_table[op].dump,
+					.module = client->cb_table[op].module,
 				};
 				return netlink_dump_start(nls, skb, nlh, &c);
 			}
diff --git a/include/rdma/rdma_netlink.h b/include/rdma/rdma_netlink.h
index 3c5363a..bd3d8b2 100644
--- a/include/rdma/rdma_netlink.h
+++ b/include/rdma/rdma_netlink.h
@@ -39,6 +39,7 @@ struct rdma_cm_id_stats {
 
 struct ibnl_client_cbs {
 	int (*dump)(struct sk_buff *skb, struct netlink_callback *nlcb);
+	struct module *module;
 };
 
 int ibnl_init(void);
-- 
1.7.7.6

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Re: [patch v3 02/11] inet_diag: pass inet_diag module to netlink_dump_start

[Eric Dumazet]

On Thu, 2012-10-04 at 12:41 +0800, Gao feng wrote:
> set netlink_dump_control.module to avoid panic.
> 
> Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
> ---
>  net/ipv4/inet_diag.c |    2 ++
>  1 files changed, 2 insertions(+), 0 deletions(-)
> 
> diff --git a/net/ipv4/inet_diag.c b/net/ipv4/inet_diag.c
> index 535584c..5ffd7bc 100644
> --- a/net/ipv4/inet_diag.c
> +++ b/net/ipv4/inet_diag.c
> @@ -981,6 +981,7 @@ static int inet_diag_rcv_msg_compat(struct sk_buff *skb, struct nlmsghdr *nlh)
>  		{
>  			struct netlink_dump_control c = {
>  				.dump = inet_diag_dump_compat,
> +				.module = THIS_MODULE,
>  			};
>  			return netlink_dump_start(net->diag_nlsk, skb, nlh, &c);
>  		}
> @@ -1010,6 +1011,7 @@ static int inet_diag_handler_dump(struct sk_buff *skb, struct nlmsghdr *h)
>  		{
>  			struct netlink_dump_control c = {
>  				.dump = inet_diag_dump,
> +				.module = THIS_MODULE,
>  			};
>  			return netlink_dump_start(net->diag_nlsk, skb, h, &c);
>  		}


I believe Pablo suggestion was to make netlink_dump_start()
automatically pass THIS_MODULE so that we dont need to change all call
sites ?

extern int __netlink_dump_start(struct sock *ssk, struct sk_buff *skb,
				  const struct nlmsghdr *nlh,
				  struct netlink_dump_control *control);

static inline int netlink_dump_start(struct sock *ssk, struct sk_buff *skb,
					const struct nlmsghdr *nlh,
					struct netlink_dump_control *control)
{
	control->module = THIS_MODULE;
	return __netlink_dump_start(ssk, skb, nlh, control);
}

or :

extern int __netlink_dump_start(struct sock *ssk, struct sk_buff *skb,
				  const struct nlmsghdr *nlh,
				  struct netlink_dump_control *control,
				  struct module *module);

static inline int netlink_dump_start(struct sock *ssk, struct sk_buff *skb,
					const struct nlmsghdr *nlh,
					struct netlink_dump_control *control)
{
	return __netlink_dump_start(ssk, skb, nlh, control, THIS_MODULE);
}

Re: [patch v3 02/11] inet_diag: pass inet_diag module to netlink_dump_start

[Gao feng]

于 2012年10月04日 13:08, Eric Dumazet 写道:
> I believe Pablo suggestion was to make netlink_dump_start()
> automatically pass THIS_MODULE so that we dont need to change all call
> sites ?

Yes, since you and Pablo both think this should be better,
I will resend this patchset.

Thanks!

Re: [patch v3 01/11] netlink: add reference of module in netlink_dump_start

[Ben Hutchings]

On Thu, 2012-10-04 at 12:41 +0800, Gao feng wrote:
> I get a panic when I use ss -a and rmmod inet_diag at the
> same time.
> 
> it's because netlink_dump use inet_diag_dump witch function
> belongs to module inet_diag.
> 
> I search the codes and find many modules have the same problem.
> We need add reference of the module witch the cb->dump belongs
> to.
> 
> Thanks for all help from Stephen,Jan,Eric,Steffen and Pablo.
> 
> Change From v2:
> 
> delete netlink_dump_done,and call module_put in netlink_dump
> and netlink_sock_destruct.
[...]
> @@ -1794,19 +1798,28 @@ int netlink_dump_start(struct sock *ssk, struct sk_buff *skb,
>  		return -ECONNREFUSED;
>  	}
>  	nlk = nlk_sk(sk);
> -	/* A dump is in progress... */
> +
>  	mutex_lock(nlk->cb_mutex);
> +	/* A dump is in progress... */
>  	if (nlk->cb) {
>  		mutex_unlock(nlk->cb_mutex);
>  		netlink_destroy_callback(cb);
> -		sock_put(sk);
> -		return -EBUSY;
> +		ret = -EBUSY;
> +		goto out;
>  	}
> +	/* add reference of module witch cb->dump belong to */
[...]

'which' not 'witch' :-)

Ben.

-- 
Ben Hutchings, Staff Engineer, Solarflare
Not speaking for my employer; that's the marketing department's job.
They asked us to note that Solarflare product names are trademarked.

Re: [patch v3 01/11] netlink: add reference of module in netlink_dump_start

[Gao feng]

于 2012年10月04日 23:41, Ben Hutchings 写道:
> 'which' not 'witch' :-)
> 
> Ben.

thanks Ben,will fix it :)