From: Aichun Li liaichun@huawei.com

mainline inclusion from mainline-v5.5-rc5 commit 07a4ddec3ce9b0a533b5f90f582f1057390d5e63 category: bugfix bugzilla: 46933 CVE: NA

-------------------

Currently, gratuitous ARP/ND packets are sent every `miimon' milliseconds. This commit allows a user to specify a custom delay through a new option, `peer_notif_delay'.

Like for `updelay' and `downdelay', this delay should be a multiple of `miimon' to avoid managing an additional work queue. The configuration logic is copied from `updelay' and `downdelay'. However, the default value cannot be set using a module parameter: Netlink or sysfs should be used to configure this feature.

When setting `miimon' to 100 and `peer_notif_delay' to 500, we can observe the 500 ms delay is respected:

20:30:19.354693 ARP, Request who-has 203.0.113.10 tell 203.0.113.10, length 28 20:30:19.874892 ARP, Request who-has 203.0.113.10 tell 203.0.113.10, length 28 20:30:20.394919 ARP, Request who-has 203.0.113.10 tell 203.0.113.10, length 28 20:30:20.914963 ARP, Request who-has 203.0.113.10 tell 203.0.113.10, length 28

In bond_mii_monitor(), I have tried to keep the lock logic readable. The change is due to the fact we cannot rely on a notification to lower the value of `bond->send_peer_notif' as `NETDEV_NOTIFY_PEERS' is only triggered once every N times, while we need to decrement the counter each time.

iproute2 also needs to be updated to be able to specify this new attribute through `ip link'.

Signed-off-by: Vincent Bernat vincent@bernat.ch Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Aichun Li liaichun@huawei.com Reviewed-by: Yue Haibing yuehaibing@huawei.com Reviewed-by: wangxiaopeng wangxiaopeng7@huawei.com Signed-off-by: Yang Yingliang yangyingliang@huawei.com --- drivers/net/bonding/bond_main.c | 31 ++++++++----- drivers/net/bonding/bond_netlink.c | 14 ++++++ drivers/net/bonding/bond_options.c | 71 +++++++++++++++++++----------- drivers/net/bonding/bond_procfs.c | 2 + drivers/net/bonding/bond_sysfs.c | 13 ++++++ include/net/bond_options.h | 1 + include/net/bonding.h | 1 + include/uapi/linux/if_link.h | 1 + tools/include/uapi/linux/if_link.h | 1 + 9 files changed, 98 insertions(+), 37 deletions(-)

diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c index c21c4291921f..b7db57e6c96a 100644 --- a/drivers/net/bonding/bond_main.c +++ b/drivers/net/bonding/bond_main.c @@ -786,6 +786,8 @@ static bool bond_should_notify_peers(struct bonding *bond) slave ? slave->dev->name : "NULL");

if (!slave || !bond->send_peer_notif || + bond->send_peer_notif % + max(1, bond->params.peer_notif_delay) != 0 || !netif_carrier_ok(bond->dev) || test_bit(__LINK_STATE_LINKWATCH_PENDING, &slave->dev->state)) return false; @@ -878,15 +880,18 @@ void bond_change_active_slave(struct bonding *bond, struct slave *new_active)

if (netif_running(bond->dev)) { bond->send_peer_notif = - bond->params.num_peer_notif; + bond->params.num_peer_notif * + max(1, bond->params.peer_notif_delay); should_notify_peers = bond_should_notify_peers(bond); }

call_netdevice_notifiers(NETDEV_BONDING_FAILOVER, bond->dev); - if (should_notify_peers) + if (should_notify_peers) { + bond->send_peer_notif--; call_netdevice_notifiers(NETDEV_NOTIFY_PEERS, bond->dev); + } } }

@@ -2315,6 +2320,7 @@ static void bond_mii_monitor(struct work_struct *work) struct bonding *bond = container_of(work, struct bonding, mii_work.work); bool should_notify_peers = false; + bool commit; unsigned long delay; struct slave *slave; struct list_head *iter; @@ -2325,12 +2331,19 @@ static void bond_mii_monitor(struct work_struct *work) goto re_arm;

rcu_read_lock(); - should_notify_peers = bond_should_notify_peers(bond); - - if (bond_miimon_inspect(bond)) { + commit = !!bond_miimon_inspect(bond); + if (bond->send_peer_notif) { + rcu_read_unlock(); + if (rtnl_trylock()) { + bond->send_peer_notif--; + rtnl_unlock(); + } + } else { rcu_read_unlock(); + }

+ if (commit) { /* Race avoidance with bond_close cancel of workqueue */ if (!rtnl_trylock()) { delay = 1; @@ -2344,8 +2357,7 @@ static void bond_mii_monitor(struct work_struct *work) bond_miimon_commit(bond);

rtnl_unlock(); /* might sleep, hold no other locks */ - } else - rcu_read_unlock(); + }

re_arm: if (bond->params.miimon) @@ -3118,10 +3130,6 @@ static int bond_master_netdev_event(unsigned long event, case NETDEV_REGISTER: bond_create_proc_entry(event_bond); break; - case NETDEV_NOTIFY_PEERS: - if (event_bond->send_peer_notif) - event_bond->send_peer_notif--; - break; default: break; } @@ -4768,6 +4776,7 @@ static int bond_check_params(struct bond_params *params) params->arp_all_targets = arp_all_targets_value; params->updelay = updelay; params->downdelay = downdelay; + params->peer_notif_delay = 0; params->use_carrier = use_carrier; params->lacp_fast = lacp_fast; params->primary[0] = 0; diff --git a/drivers/net/bonding/bond_netlink.c b/drivers/net/bonding/bond_netlink.c index fbcd8a752ee7..d446b9423bae 100644 --- a/drivers/net/bonding/bond_netlink.c +++ b/drivers/net/bonding/bond_netlink.c @@ -112,6 +112,7 @@ static const struct nla_policy bond_policy[IFLA_BOND_MAX + 1] = { [IFLA_BOND_AD_ACTOR_SYSTEM] = { .type = NLA_BINARY, .len = ETH_ALEN }, [IFLA_BOND_TLB_DYNAMIC_LB] = { .type = NLA_U8 }, + [IFLA_BOND_PEER_NOTIF_DELAY] = { .type = NLA_U32 }, };

static const struct nla_policy bond_slave_policy[IFLA_BOND_SLAVE_MAX + 1] = { @@ -219,6 +220,14 @@ static int bond_changelink(struct net_device *bond_dev, struct nlattr *tb[], if (err) return err; } + if (data[IFLA_BOND_PEER_NOTIF_DELAY]) { + int delay = nla_get_u32(data[IFLA_BOND_PEER_NOTIF_DELAY]); + + bond_opt_initval(&newval, delay); + err = __bond_opt_set(bond, BOND_OPT_PEER_NOTIF_DELAY, &newval); + if (err) + return err; + } if (data[IFLA_BOND_USE_CARRIER]) { int use_carrier = nla_get_u8(data[IFLA_BOND_USE_CARRIER]);

@@ -497,6 +506,7 @@ static size_t bond_get_size(const struct net_device *bond_dev) nla_total_size(sizeof(u16)) + /* IFLA_BOND_AD_USER_PORT_KEY */ nla_total_size(ETH_ALEN) + /* IFLA_BOND_AD_ACTOR_SYSTEM */ nla_total_size(sizeof(u8)) + /* IFLA_BOND_TLB_DYNAMIC_LB */ + nla_total_size(sizeof(u32)) + /* IFLA_BOND_PEER_NOTIF_DELAY */ 0; }

@@ -539,6 +549,10 @@ static int bond_fill_info(struct sk_buff *skb, bond->params.downdelay * bond->params.miimon)) goto nla_put_failure;

+ if (nla_put_u32(skb, IFLA_BOND_PEER_NOTIF_DELAY, + bond->params.downdelay * bond->params.miimon)) + goto nla_put_failure; + if (nla_put_u8(skb, IFLA_BOND_USE_CARRIER, bond->params.use_carrier)) goto nla_put_failure;

diff --git a/drivers/net/bonding/bond_options.c b/drivers/net/bonding/bond_options.c index 80867bd8f44c..7e07e213f4c2 100644 --- a/drivers/net/bonding/bond_options.c +++ b/drivers/net/bonding/bond_options.c @@ -28,6 +28,8 @@ static int bond_option_updelay_set(struct bonding *bond, const struct bond_opt_value *newval); static int bond_option_downdelay_set(struct bonding *bond, const struct bond_opt_value *newval); +static int bond_option_peer_notif_delay_set(struct bonding *bond, + const struct bond_opt_value *newval); static int bond_option_use_carrier_set(struct bonding *bond, const struct bond_opt_value *newval); static int bond_option_arp_interval_set(struct bonding *bond, @@ -428,6 +430,13 @@ static const struct bond_option bond_opts[BOND_OPT_LAST] = { .desc = "Number of peer notifications to send on failover event", .values = bond_num_peer_notif_tbl, .set = bond_option_num_peer_notif_set + }, + [BOND_OPT_PEER_NOTIF_DELAY] = { + .id = BOND_OPT_PEER_NOTIF_DELAY, + .name = "peer_notif_delay", + .desc = "Delay between each peer notification on failover event, in milliseconds", + .values = bond_intmax_tbl, + .set = bond_option_peer_notif_delay_set } };

@@ -850,6 +859,9 @@ static int bond_option_miimon_set(struct bonding *bond, if (bond->params.downdelay) netdev_dbg(bond->dev, "Note: Updating downdelay (to %d) since it is a multiple of the miimon value\n", bond->params.downdelay * bond->params.miimon); + if (bond->params.peer_notif_delay) + netdev_dbg(bond->dev, "Note: Updating peer_notif_delay (to %d) since it is a multiple of the miimon value\n", + bond->params.peer_notif_delay * bond->params.miimon); if (newval->value && bond->params.arp_interval) { netdev_dbg(bond->dev, "MII monitoring cannot be used with ARP monitoring - disabling ARP monitoring...\n"); bond->params.arp_interval = 0; @@ -873,52 +885,59 @@ static int bond_option_miimon_set(struct bonding *bond, return 0; }

-/* Set up and down delays. These must be multiples of the - * MII monitoring value, and are stored internally as the multiplier. - * Thus, we must translate to MS for the real world. +/* Set up, down and peer notification delays. These must be multiples + * of the MII monitoring value, and are stored internally as the + * multiplier. Thus, we must translate to MS for the real world. */ -static int bond_option_updelay_set(struct bonding *bond, - const struct bond_opt_value *newval) +static int _bond_option_delay_set(struct bonding *bond, + const struct bond_opt_value *newval, + const char *name, + int *target) { int value = newval->value;

if (!bond->params.miimon) { - netdev_err(bond->dev, "Unable to set up delay as MII monitoring is disabled\n"); + netdev_err(bond->dev, "Unable to set %s as MII monitoring is disabled\n", + name); return -EPERM; } if ((value % bond->params.miimon) != 0) { - netdev_warn(bond->dev, "up delay (%d) is not a multiple of miimon (%d), updelay rounded to %d ms\n", + netdev_warn(bond->dev, + "%s (%d) is not a multiple of miimon (%d), value rounded to %d ms\n", + name, value, bond->params.miimon, (value / bond->params.miimon) * bond->params.miimon); } - bond->params.updelay = value / bond->params.miimon; - netdev_dbg(bond->dev, "Setting up delay to %d\n", - bond->params.updelay * bond->params.miimon); + *target = value / bond->params.miimon; + netdev_dbg(bond->dev, "Setting %s to %d\n", + name, + *target * bond->params.miimon);

return 0; }

+static int bond_option_updelay_set(struct bonding *bond, + const struct bond_opt_value *newval) +{ + return _bond_option_delay_set(bond, newval, "up delay", + &bond->params.updelay); +} + static int bond_option_downdelay_set(struct bonding *bond, const struct bond_opt_value *newval) { - int value = newval->value; - - if (!bond->params.miimon) { - netdev_err(bond->dev, "Unable to set down delay as MII monitoring is disabled\n"); - return -EPERM; - } - if ((value % bond->params.miimon) != 0) { - netdev_warn(bond->dev, "down delay (%d) is not a multiple of miimon (%d), delay rounded to %d ms\n", - value, bond->params.miimon, - (value / bond->params.miimon) * - bond->params.miimon); - } - bond->params.downdelay = value / bond->params.miimon; - netdev_dbg(bond->dev, "Setting down delay to %d\n", - bond->params.downdelay * bond->params.miimon); + return _bond_option_delay_set(bond, newval, "down delay", + &bond->params.downdelay); +}

- return 0; +static int bond_option_peer_notif_delay_set(struct bonding *bond, + const struct bond_opt_value *newval) +{ + int ret = _bond_option_delay_set(bond, newval, + "peer notification delay", + &bond->params.peer_notif_delay); + return ret; }

static int bond_option_use_carrier_set(struct bonding *bond, diff --git a/drivers/net/bonding/bond_procfs.c b/drivers/net/bonding/bond_procfs.c index 9f7d83e827c3..fd5c9cbe45b1 100644 --- a/drivers/net/bonding/bond_procfs.c +++ b/drivers/net/bonding/bond_procfs.c @@ -104,6 +104,8 @@ static void bond_info_show_master(struct seq_file *seq) bond->params.updelay * bond->params.miimon); seq_printf(seq, "Down Delay (ms): %d\n", bond->params.downdelay * bond->params.miimon); + seq_printf(seq, "Peer Notification Delay (ms): %d\n", + bond->params.peer_notif_delay * bond->params.miimon);

/* ARP information */ diff --git a/drivers/net/bonding/bond_sysfs.c b/drivers/net/bonding/bond_sysfs.c index 35847250da5a..0ecafe115f32 100644 --- a/drivers/net/bonding/bond_sysfs.c +++ b/drivers/net/bonding/bond_sysfs.c @@ -343,6 +343,18 @@ static ssize_t bonding_show_updelay(struct device *d, static DEVICE_ATTR(updelay, 0644, bonding_show_updelay, bonding_sysfs_store_option);

+static ssize_t bonding_show_peer_notif_delay(struct device *d, + struct device_attribute *attr, + char *buf) +{ + struct bonding *bond = to_bond(d); + + return sprintf(buf, "%d\n", + bond->params.peer_notif_delay * bond->params.miimon); +} +static DEVICE_ATTR(peer_notif_delay, 0644, + bonding_show_peer_notif_delay, bonding_sysfs_store_option); + /* Show the LACP interval. */ static ssize_t bonding_show_lacp(struct device *d, struct device_attribute *attr, @@ -734,6 +746,7 @@ static struct attribute *per_bond_attrs[] = { &dev_attr_arp_ip_target.attr, &dev_attr_downdelay.attr, &dev_attr_updelay.attr, + &dev_attr_peer_notif_delay.attr, &dev_attr_lacp_rate.attr, &dev_attr_ad_select.attr, &dev_attr_xmit_hash_policy.attr, diff --git a/include/net/bond_options.h b/include/net/bond_options.h index d79d28f5318c..6889a04d9520 100644 --- a/include/net/bond_options.h +++ b/include/net/bond_options.h @@ -67,6 +67,7 @@ enum { BOND_OPT_AD_ACTOR_SYSTEM, BOND_OPT_AD_USER_PORT_KEY, BOND_OPT_NUM_PEER_NOTIF_ALIAS, + BOND_OPT_PEER_NOTIF_DELAY, BOND_OPT_LAST };

diff --git a/include/net/bonding.h b/include/net/bonding.h index 58a8c2b66aa5..a548bada8e8e 100644 --- a/include/net/bonding.h +++ b/include/net/bonding.h @@ -114,6 +114,7 @@ struct bond_params { int fail_over_mac; int updelay; int downdelay; + int peer_notif_delay; int lacp_fast; unsigned int min_links; int ad_select; diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h index 9d8eac55da5a..f9a0359ceb6a 100644 --- a/include/uapi/linux/if_link.h +++ b/include/uapi/linux/if_link.h @@ -615,6 +615,7 @@ enum { IFLA_BOND_AD_USER_PORT_KEY, IFLA_BOND_AD_ACTOR_SYSTEM, IFLA_BOND_TLB_DYNAMIC_LB, + IFLA_BOND_PEER_NOTIF_DELAY, __IFLA_BOND_MAX, };

diff --git a/tools/include/uapi/linux/if_link.h b/tools/include/uapi/linux/if_link.h index 43391e2d1153..f57af58f1919 100644 --- a/tools/include/uapi/linux/if_link.h +++ b/tools/include/uapi/linux/if_link.h @@ -614,6 +614,7 @@ enum { IFLA_BOND_AD_USER_PORT_KEY, IFLA_BOND_AD_ACTOR_SYSTEM, IFLA_BOND_TLB_DYNAMIC_LB, + IFLA_BOND_PEER_NOTIF_DELAY, __IFLA_BOND_MAX, };

From: Aichun Li liaichun@huawei.com

mainline inclusion from mainline-v5.5-rc5 commit 0307d589c4d6f84349afb7a53717baa2392f6a38 category: bugfix bugzilla: 46933 CVE: NA

-------------------

Ability to tweak the interval between peer notifications has been added in 07a4ddec3ce9 ("bonding: add an option to specify a delay between peer notifications") but the documentation was not updated.

Signed-off-by: Vincent Bernat vincent@bernat.ch Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Aichun Li liaichun@huawei.com Reviewed-by: Yue Haibing yuehaibing@huawei.com Reviewed-by: wangxiaopeng wangxiaopeng7@huawei.com Signed-off-by: Yang Yingliang yangyingliang@huawei.com --- Documentation/networking/bonding.txt | 16 +++++++++++++--- 1 file changed, 13 insertions(+), 3 deletions(-)

diff --git a/Documentation/networking/bonding.txt b/Documentation/networking/bonding.txt index d3e5dd26db12..e3abfbd32f71 100644 --- a/Documentation/networking/bonding.txt +++ b/Documentation/networking/bonding.txt @@ -706,9 +706,9 @@ num_unsol_na unsolicited IPv6 Neighbor Advertisements) to be issued after a failover event. As soon as the link is up on the new slave (possibly immediately) a peer notification is sent on the - bonding device and each VLAN sub-device. This is repeated at - each link monitor interval (arp_interval or miimon, whichever - is active) if the number is greater than 1. + bonding device and each VLAN sub-device. This is repeated at + the rate specified by peer_notif_delay if the number is + greater than 1.

The valid range is 0 - 255; the default value is 1. These options affect only the active-backup mode. These options were added for @@ -727,6 +727,16 @@ packets_per_slave The valid range is 0 - 65535; the default value is 1. This option has effect only in balance-rr mode.

+peer_notif_delay + + Specify the delay, in milliseconds, between each peer + notification (gratuitous ARP and unsolicited IPv6 Neighbor + Advertisement) when they are issued after a failover event. + This delay should be a multiple of the link monitor interval + (arp_interval or miimon, whichever is active). The default + value is 0 which means to match the value of the link monitor + interval. + primary

A string (eth0, eth2, etc) specifying which slave is the