Do we need to add this to block Spanning Tree from being enabled with hairpin mode? I am not sure what the exact usage of hairpin mode and if it is possible to create loops and get STP confusion. For comment only, do not apply as is. --- a/net/bridge/br_ioctl.c 2009-08-14 14:28:19.917690805 -0700 +++ b/net/bridge/br_ioctl.c 2009-08-14 14:29:54.078271361 -0700 @@ -259,8 +259,7 @@ static int old_dev_ioctl(struct net_devi if (!capable(CAP_NET_ADMIN)) return -EPERM; - br_stp_set_enabled(br, args[1]); - return 0; + return br_stp_set_enabled(br, args[1]); case BRCTL_SET_BRIDGE_PRIORITY: if (!capable(CAP_NET_ADMIN)) --- a/net/bridge/br_stp_if.c 2009-08-14 14:24:30.022315573 -0700 +++ b/net/bridge/br_stp_if.c 2009-08-14 14:35:25.819566113 -0700 @@ -160,17 +160,26 @@ static void br_stp_stop(struct net_bridg br->stp_enabled = BR_NO_STP; } -void br_stp_set_enabled(struct net_bridge *br, unsigned long val) +int br_stp_set_enabled(struct net_bridge *br, unsigned long val) { ASSERT_RTNL(); if (val) { + struct net_bridge_port *p; + list_for_each_entry_rcu(p, &br->port_list, list) { + if (p->flags & BR_HAIRPIN_MODE) + return -EINVAL; + } + + if (br->stp_enabled == BR_NO_STP) br_stp_start(br); } else { if (br->stp_enabled != BR_NO_STP) br_stp_stop(br); } + + return 0; } /* called under bridge lock */ --- a/net/bridge/br_sysfs_br.c 2009-08-14 14:24:36.874256194 -0700 +++ b/net/bridge/br_sysfs_br.c 2009-08-14 14:33:26.025441102 -0700 @@ -164,6 +164,7 @@ static ssize_t store_stp_state(struct de struct net_bridge *br = to_bridge(d); char *endp; unsigned long val; + int ret; if (!capable(CAP_NET_ADMIN)) return -EPERM; @@ -174,10 +175,11 @@ static ssize_t store_stp_state(struct de if (!rtnl_trylock()) return restart_syscall(); - br_stp_set_enabled(br, val); + + ret = br_stp_set_enabled(br, val); rtnl_unlock(); - return len; + return (ret == 0) ? len : ret; } static DEVICE_ATTR(stp_state, S_IRUGO | S_IWUSR, show_stp_state, store_stp_state); --- a/net/bridge/br_sysfs_if.c 2009-08-14 14:24:36.888356879 -0700 +++ b/net/bridge/br_sysfs_if.c 2009-08-14 14:34:55.339272738 -0700 @@ -150,10 +150,13 @@ static ssize_t show_hairpin_mode(struct } static ssize_t store_hairpin_mode(struct net_bridge_port *p, unsigned long v) { - if (v) + if (!v) + p->flags &= ~BR_HAIRPIN_MODE; + else if (p->br->stp_enabled == BR_NO_STP) p->flags |= BR_HAIRPIN_MODE; else - p->flags &= ~BR_HAIRPIN_MODE; + return -EINVAL; + return 0; } static BRPORT_ATTR(hairpin_mode, S_IRUGO | S_IWUSR, --- a/net/bridge/br_private.h 2009-08-14 14:34:05.263278817 -0700 +++ b/net/bridge/br_private.h 2009-08-14 14:34:15.717297908 -0700 @@ -218,7 +218,7 @@ extern void br_become_designated_port(st /* br_stp_if.c */ extern void br_stp_enable_bridge(struct net_bridge *br); extern void br_stp_disable_bridge(struct net_bridge *br); -extern void br_stp_set_enabled(struct net_bridge *br, unsigned long val); +extern int br_stp_set_enabled(struct net_bridge *br, unsigned long val); extern void br_stp_enable_port(struct net_bridge_port *p); extern void br_stp_disable_port(struct net_bridge_port *p); extern void br_stp_recalculate_bridge_id(struct net_bridge *br); _______________________________________________ Bridge mailing list Bridge@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/bridge