From 1a50307ba1826e4da0024e64b245ce4eadf7688a Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Thu, 18 Mar 2010 14:24:42 +0000 Subject: [PATCH] netlink: fix NETLINK_RECV_NO_ENOBUFS in netlink_set_err() Currently, ENOBUFS errors are reported to the socket via netlink_set_err() even if NETLINK_RECV_NO_ENOBUFS is set. However, that should not happen. This fixes this problem and it changes the prototype of netlink_set_err() to return the number of sockets that have set the NETLINK_RECV_NO_ENOBUFS socket option. This return value is used in the next patch in these bugfix series. Signed-off-by: Pablo Neira Ayuso Signed-off-by: David S. Miller --- include/linux/netlink.h | 2 +- net/netlink/af_netlink.c | 17 ++++++++++++++--- 2 files changed, 15 insertions(+), 4 deletions(-) diff --git a/include/linux/netlink.h b/include/linux/netlink.h index fde27c017326..6eaca5e1e8ca 100644 --- a/include/linux/netlink.h +++ b/include/linux/netlink.h @@ -188,7 +188,7 @@ extern int netlink_has_listeners(struct sock *sk, unsigned int group); extern int netlink_unicast(struct sock *ssk, struct sk_buff *skb, __u32 pid, int nonblock); extern int netlink_broadcast(struct sock *ssk, struct sk_buff *skb, __u32 pid, __u32 group, gfp_t allocation); -extern void netlink_set_err(struct sock *ssk, __u32 pid, __u32 group, int code); +extern int netlink_set_err(struct sock *ssk, __u32 pid, __u32 group, int code); extern int netlink_register_notifier(struct notifier_block *nb); extern int netlink_unregister_notifier(struct notifier_block *nb); diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c index 320d0423a240..acbbae1e89b5 100644 --- a/net/netlink/af_netlink.c +++ b/net/netlink/af_netlink.c @@ -1093,6 +1093,7 @@ static inline int do_one_set_err(struct sock *sk, struct netlink_set_err_data *p) { struct netlink_sock *nlk = nlk_sk(sk); + int ret = 0; if (sk == p->exclude_sk) goto out; @@ -1104,10 +1105,15 @@ static inline int do_one_set_err(struct sock *sk, !test_bit(p->group - 1, nlk->groups)) goto out; + if (p->code == ENOBUFS && nlk->flags & NETLINK_RECV_NO_ENOBUFS) { + ret = 1; + goto out; + } + sk->sk_err = p->code; sk->sk_error_report(sk); out: - return 0; + return ret; } /** @@ -1116,12 +1122,16 @@ out: * @pid: the PID of a process that we want to skip (if any) * @groups: the broadcast group that will notice the error * @code: error code, must be negative (as usual in kernelspace) + * + * This function returns the number of broadcast listeners that have set the + * NETLINK_RECV_NO_ENOBUFS socket option. */ -void netlink_set_err(struct sock *ssk, u32 pid, u32 group, int code) +int netlink_set_err(struct sock *ssk, u32 pid, u32 group, int code) { struct netlink_set_err_data info; struct hlist_node *node; struct sock *sk; + int ret = 0; info.exclude_sk = ssk; info.pid = pid; @@ -1132,9 +1142,10 @@ void netlink_set_err(struct sock *ssk, u32 pid, u32 group, int code) read_lock(&nl_table_lock); sk_for_each_bound(sk, node, &nl_table[ssk->sk_protocol].mc_list) - do_one_set_err(sk, &info); + ret += do_one_set_err(sk, &info); read_unlock(&nl_table_lock); + return ret; } EXPORT_SYMBOL(netlink_set_err);