From 311633b604063a8a5d3fbc74d0565b42df721f68 Mon Sep 17 00:00:00 2001 From: Cong Wang Date: Tue, 9 Jul 2019 23:24:54 -0700 Subject: hsr: switch ->dellink() to ->ndo_uninit() Switching from ->priv_destructor to dellink() has an unexpected consequence: existing RCU readers, that is, hsr_port_get_hsr() callers, may still be able to read the port list. Instead of checking the return value of each hsr_port_get_hsr(), we can just move it to ->ndo_uninit() which is called after device unregister and synchronize_net(), and we still have RTNL lock there. Fixes: b9a1e627405d ("hsr: implement dellink to clean up resources") Fixes: edf070a0fb45 ("hsr: fix a NULL pointer deref in hsr_dev_xmit()") Reported-by: syzbot+097ef84cdc95843fbaa8@syzkaller.appspotmail.com Cc: Arvid Brodin Signed-off-by: Cong Wang Signed-off-by: David S. Miller --- net/hsr/hsr_netlink.c | 7 ------- 1 file changed, 7 deletions(-) (limited to 'net/hsr/hsr_netlink.c') diff --git a/net/hsr/hsr_netlink.c b/net/hsr/hsr_netlink.c index 160edd24de4e..8f8337f893ba 100644 --- a/net/hsr/hsr_netlink.c +++ b/net/hsr/hsr_netlink.c @@ -69,12 +69,6 @@ static int hsr_newlink(struct net *src_net, struct net_device *dev, return hsr_dev_finalize(dev, link, multicast_spec, hsr_version); } -static void hsr_dellink(struct net_device *hsr_dev, struct list_head *head) -{ - hsr_dev_destroy(hsr_dev); - unregister_netdevice_queue(hsr_dev, head); -} - static int hsr_fill_info(struct sk_buff *skb, const struct net_device *dev) { struct hsr_priv *hsr; @@ -119,7 +113,6 @@ static struct rtnl_link_ops hsr_link_ops __read_mostly = { .priv_size = sizeof(struct hsr_priv), .setup = hsr_dev_setup, .newlink = hsr_newlink, - .dellink = hsr_dellink, .fill_info = hsr_fill_info, }; -- cgit v1.2.3-59-g8ed1b