From 0465277f6b3fd0535428ae935644ac30ce903de0 Mon Sep 17 00:00:00 2001 From: Nicolas Dichtel Date: Fri, 22 Mar 2013 06:28:42 +0000 Subject: [PATCH] ipv4: provide addr and netconf dump consistency info This patch takes benefit of dev_addr_genid and dev_base_seq to check if a change occurs during a netlink dump. If a change is detected, the flag NLM_F_DUMP_INTR is set in the first message after the dump was interrupted. Note that seq and prev_seq must be reset between each family in rtnl_dump_all() because they are specific to each family. Reported-by: Junwei Zhang Reported-by: Hongjun Li Signed-off-by: Nicolas Dichtel Signed-off-by: David S. Miller --- net/core/rtnetlink.c | 5 ++++- net/ipv4/devinet.c | 6 ++++++ 2 files changed, 10 insertions(+), 1 deletion(-) diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index 751f1244b648..aeb81316a704 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -1929,8 +1929,11 @@ static int rtnl_dump_all(struct sk_buff *skb, struct netlink_callback *cb) if (rtnl_msg_handlers[idx] == NULL || rtnl_msg_handlers[idx][type].dumpit == NULL) continue; - if (idx > s_idx) + if (idx > s_idx) { memset(&cb->args[0], 0, sizeof(cb->args)); + cb->prev_seq = 0; + cb->seq = 0; + } if (rtnl_msg_handlers[idx][type].dumpit(skb, cb)) break; } diff --git a/net/ipv4/devinet.c b/net/ipv4/devinet.c index 20a9f9274f3f..5d985e367535 100644 --- a/net/ipv4/devinet.c +++ b/net/ipv4/devinet.c @@ -1499,6 +1499,8 @@ static int inet_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb) idx = 0; head = &net->dev_index_head[h]; rcu_read_lock(); + cb->seq = atomic_read(&net->ipv4.dev_addr_genid) ^ + net->dev_base_seq; hlist_for_each_entry_rcu(dev, head, index_hlist) { if (idx < s_idx) goto cont; @@ -1519,6 +1521,7 @@ static int inet_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb) rcu_read_unlock(); goto done; } + nl_dump_check_consistent(cb, nlmsg_hdr(skb)); } cont: idx++; @@ -1807,6 +1810,8 @@ static int inet_netconf_dump_devconf(struct sk_buff *skb, idx = 0; head = &net->dev_index_head[h]; rcu_read_lock(); + cb->seq = atomic_read(&net->ipv4.dev_addr_genid) ^ + net->dev_base_seq; hlist_for_each_entry_rcu(dev, head, index_hlist) { if (idx < s_idx) goto cont; @@ -1824,6 +1829,7 @@ static int inet_netconf_dump_devconf(struct sk_buff *skb, rcu_read_unlock(); goto done; } + nl_dump_check_consistent(cb, nlmsg_hdr(skb)); cont: idx++; }