From 3e41af90767dcf8e5ca91cfbbbcb772584940df9 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Sun, 11 Feb 2024 21:44:04 +0000 Subject: [PATCH] rtnetlink: use xarray iterator to implement rtnl_dump_ifinfo() Adopt net->dev_by_index as I did in commit 0e0939c0adf9 ("net-procfs: use xarray iterator to implement /proc/net/dev") This makes sure an existing device is always visible in the dump, regardless of concurrent insertions/deletions. v2: added suggestions from Jakub Kicinski and Ido Schimmel, thanks for the help ! Link: https://lore.kernel.org/all/20240209142441.6c56435b@kernel.org/ Link: https://lore.kernel.org/all/ZckR-XOsULLI9EHc@shredder/ Signed-off-by: Eric Dumazet Reviewed-by: Ido Schimmel Link: https://lore.kernel.org/r/20240211214404.1882191-3-edumazet@google.com Signed-off-by: Jakub Kicinski --- net/core/rtnetlink.c | 60 ++++++++++++++++---------------------------- 1 file changed, 21 insertions(+), 39 deletions(-) diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index 31f433950c8d..6f1c5537e842 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -2188,25 +2188,22 @@ static int rtnl_valid_dump_ifinfo_req(const struct nlmsghdr *nlh, static int rtnl_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb) { + const struct rtnl_link_ops *kind_ops = NULL; struct netlink_ext_ack *extack = cb->extack; const struct nlmsghdr *nlh = cb->nlh; struct net *net = sock_net(skb->sk); - struct net *tgt_net = net; - int h, s_h; - int idx = 0, s_idx; - struct net_device *dev; - struct hlist_head *head; - struct nlattr *tb[IFLA_MAX+1]; - u32 ext_filter_mask = 0; - const struct rtnl_link_ops *kind_ops = NULL; unsigned int flags = NLM_F_MULTI; + struct nlattr *tb[IFLA_MAX+1]; + struct { + unsigned long ifindex; + } *ctx = (void *)cb->ctx; + struct net *tgt_net = net; + u32 ext_filter_mask = 0; + struct net_device *dev; int master_idx = 0; int netnsid = -1; int err, i; - s_h = cb->args[0]; - s_idx = cb->args[1]; - err = rtnl_valid_dump_ifinfo_req(nlh, cb->strict_check, tb, extack); if (err < 0) { if (cb->strict_check) @@ -2250,36 +2247,21 @@ static int rtnl_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb) flags |= NLM_F_DUMP_FILTERED; walk_entries: - for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) { - idx = 0; - head = &tgt_net->dev_index_head[h]; - hlist_for_each_entry(dev, head, index_hlist) { - if (link_dump_filtered(dev, master_idx, kind_ops)) - goto cont; - if (idx < s_idx) - goto cont; - err = rtnl_fill_ifinfo(skb, dev, net, - RTM_NEWLINK, - NETLINK_CB(cb->skb).portid, - nlh->nlmsg_seq, 0, flags, - ext_filter_mask, 0, NULL, 0, - netnsid, GFP_KERNEL); - - if (err < 0) { - if (likely(skb->len)) - goto out; - - goto out_err; - } -cont: - idx++; + err = 0; + for_each_netdev_dump(tgt_net, dev, ctx->ifindex) { + if (link_dump_filtered(dev, master_idx, kind_ops)) + continue; + err = rtnl_fill_ifinfo(skb, dev, net, RTM_NEWLINK, + NETLINK_CB(cb->skb).portid, + nlh->nlmsg_seq, 0, flags, + ext_filter_mask, 0, NULL, 0, + netnsid, GFP_KERNEL); + if (err < 0) { + if (likely(skb->len)) + err = skb->len; + break; } } -out: - err = skb->len; -out_err: - cb->args[1] = idx; - cb->args[0] = h; cb->seq = tgt_net->dev_base_seq; nl_dump_check_consistent(cb, nlmsg_hdr(skb)); if (netnsid >= 0)