[PATCH 3/3] netlink: Lock out table resizes while dumping Netlink sockets
From: Thomas Graf <tgraf@suug.ch>
Date: 2015-01-20 13:20:40
Also in:
netfilter-devel
Subsystem:
networking [general], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
Lock out table resizes while dumping Netlink sockets to user space. This keeps disruptions to a minimum for readers which don't handle the NLM_F_DUMP_INTR flag. Signed-off-by: Thomas Graf <tgraf@suug.ch> --- net/netlink/diag.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/net/netlink/diag.c b/net/netlink/diag.c
index 50aa385..be4ea6e 100644
--- a/net/netlink/diag.c
+++ b/net/netlink/diag.c@@ -114,6 +114,8 @@ static int __netlink_diag_dump(struct sk_buff *skb, struct netlink_callback *cb, req = nlmsg_data(cb->nlh); cb->seq = atomic_read(&nl_table_seq); + mutex_lock(&ht->mutex); + for (i = 0; i < htbl->size; i++) { struct rhash_head *pos;
@@ -161,6 +163,7 @@ static int __netlink_diag_dump(struct sk_buff *skb, struct netlink_callback *cb, num++; } done: + mutex_unlock(&ht->mutex); cb->args[0] = num; cb->args[1] = protocol;
--
1.9.3