6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Eric Dumazet <edumazet@xxxxxxxxxx> [ Upstream commit e0f89d2864b062b027196925ea19f94b2ce50d6a ] - Use for_each_netdev_dump() to no longer rely on net->dev_index_head hash table. - No longer care of net->dev_base_seq - Fix return value at the end of a dump, so that NLMSG_DONE can be appended to current skb, saving one recvmsg() system call. - No longer grab RTNL, RCU protection is enough, afer adding one READ_ONCE(mdev->input_enabled) in mpls_netconf_fill_devconf() Signed-off-by: Eric Dumazet <edumazet@xxxxxxxxxx> Link: https://lore.kernel.org/r/20240410111951.2673193-1-edumazet@xxxxxxxxxx Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx> Stable-dep-of: 5be2062e3080 ("mpls: Handle error of rtnl_register_module().") Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- net/mpls/af_mpls.c | 59 +++++++++++++++++----------------------------- 1 file changed, 22 insertions(+), 37 deletions(-) diff --git a/net/mpls/af_mpls.c b/net/mpls/af_mpls.c index 1af29af653885..ba034fcd59f0d 100644 --- a/net/mpls/af_mpls.c +++ b/net/mpls/af_mpls.c @@ -1154,7 +1154,7 @@ static int mpls_netconf_fill_devconf(struct sk_buff *skb, struct mpls_dev *mdev, if ((all || type == NETCONFA_INPUT) && nla_put_s32(skb, NETCONFA_INPUT, - mdev->input_enabled) < 0) + READ_ONCE(mdev->input_enabled)) < 0) goto nla_put_failure; nlmsg_end(skb, nlh); @@ -1303,11 +1303,12 @@ static int mpls_netconf_dump_devconf(struct sk_buff *skb, { const struct nlmsghdr *nlh = cb->nlh; struct net *net = sock_net(skb->sk); - struct hlist_head *head; + struct { + unsigned long ifindex; + } *ctx = (void *)cb->ctx; struct net_device *dev; struct mpls_dev *mdev; - int idx, s_idx; - int h, s_h; + int err = 0; if (cb->strict_check) { struct netlink_ext_ack *extack = cb->extack; @@ -1324,40 +1325,23 @@ static int mpls_netconf_dump_devconf(struct sk_buff *skb, } } - s_h = cb->args[0]; - s_idx = idx = cb->args[1]; - - for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) { - idx = 0; - head = &net->dev_index_head[h]; - rcu_read_lock(); - cb->seq = net->dev_base_seq; - hlist_for_each_entry_rcu(dev, head, index_hlist) { - if (idx < s_idx) - goto cont; - mdev = mpls_dev_get(dev); - if (!mdev) - goto cont; - if (mpls_netconf_fill_devconf(skb, mdev, - NETLINK_CB(cb->skb).portid, - nlh->nlmsg_seq, - RTM_NEWNETCONF, - NLM_F_MULTI, - NETCONFA_ALL) < 0) { - rcu_read_unlock(); - goto done; - } - nl_dump_check_consistent(cb, nlmsg_hdr(skb)); -cont: - idx++; - } - rcu_read_unlock(); + rcu_read_lock(); + for_each_netdev_dump(net, dev, ctx->ifindex) { + mdev = mpls_dev_get(dev); + if (!mdev) + continue; + err = mpls_netconf_fill_devconf(skb, mdev, + NETLINK_CB(cb->skb).portid, + nlh->nlmsg_seq, + RTM_NEWNETCONF, + NLM_F_MULTI, + NETCONFA_ALL); + if (err < 0) + break; } -done: - cb->args[0] = h; - cb->args[1] = idx; + rcu_read_unlock(); - return skb->len; + return err; } #define MPLS_PERDEV_SYSCTL_OFFSET(field) \ @@ -2771,7 +2755,8 @@ static int __init mpls_init(void) mpls_getroute, mpls_dump_routes, 0); rtnl_register_module(THIS_MODULE, PF_MPLS, RTM_GETNETCONF, mpls_netconf_get_devconf, - mpls_netconf_dump_devconf, 0); + mpls_netconf_dump_devconf, + RTNL_FLAG_DUMP_UNLOCKED); err = ipgre_tunnel_encap_add_mpls_ops(); if (err) pr_err("Can't add mpls over gre tunnel ops\n"); -- 2.43.0
