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Miller" , Jakub Kicinski , Paolo Abeni Cc: Simon Horman , Ido Schimmel , Nikolay Aleksandrov , netdev@vger.kernel.org, eric.dumazet@gmail.com, Eric Dumazet Content-Type: text/plain; charset="UTF-8" Add READ_ONCE()/WRITE_ONCE() annotations around p->designated_port This is needed at least for sysfs show_designated_port(), BRCTL_GET_PORT_INFO and upcoming RTNL avoidance in "ip link" dumps (cf br_port_fill_attrs()). Signed-off-by: Eric Dumazet Reviewed-by: Ido Schimmel --- net/bridge/br_ioctl.c | 2 +- net/bridge/br_netlink.c | 3 ++- net/bridge/br_stp.c | 4 ++-- net/bridge/br_stp_if.c | 2 +- net/bridge/br_sysfs_if.c | 2 +- 5 files changed, 7 insertions(+), 6 deletions(-) diff --git a/net/bridge/br_ioctl.c b/net/bridge/br_ioctl.c index a507c7b369ac49803019cdca7836c7fb9ef4459e..2be802991f70ab3ce48ade5da6d1488e072dbec6 100644 --- a/net/bridge/br_ioctl.c +++ b/net/bridge/br_ioctl.c @@ -258,7 +258,7 @@ int br_dev_siocdevprivate(struct net_device *dev, struct ifreq *rq, memcpy(&p.designated_root, &pt->designated_root, 8); memcpy(&p.designated_bridge, &pt->designated_bridge, 8); p.port_id = pt->port_id; - p.designated_port = pt->designated_port; + p.designated_port = READ_ONCE(pt->designated_port); p.path_cost = READ_ONCE(pt->path_cost); p.designated_cost = READ_ONCE(pt->designated_cost); p.state = pt->state; diff --git a/net/bridge/br_netlink.c b/net/bridge/br_netlink.c index 296f62ebdd4a6f3d404b5902fe661995bd1ca0f5..a722db89aef6bbb6ecc77c7e0f173dc79418797f 100644 --- a/net/bridge/br_netlink.c +++ b/net/bridge/br_netlink.c @@ -263,7 +263,8 @@ static int br_port_fill_attrs(struct sk_buff *skb, &p->designated_root) || nla_put(skb, IFLA_BRPORT_BRIDGE_ID, sizeof(struct ifla_bridge_id), &p->designated_bridge) || - nla_put_u16(skb, IFLA_BRPORT_DESIGNATED_PORT, p->designated_port) || + nla_put_u16(skb, IFLA_BRPORT_DESIGNATED_PORT, + READ_ONCE(p->designated_port)) || nla_put_u16(skb, IFLA_BRPORT_DESIGNATED_COST, READ_ONCE(p->designated_cost)) || nla_put_u16(skb, IFLA_BRPORT_ID, p->port_id) || diff --git a/net/bridge/br_stp.c b/net/bridge/br_stp.c index 88da86a6ba4406ac77d0b13e0a340e87e281c11a..f5ea14bb8fb865045d50fb09296d0db466e8fc6e 100644 --- a/net/bridge/br_stp.c +++ b/net/bridge/br_stp.c @@ -261,7 +261,7 @@ static void br_record_config_information(struct net_bridge_port *p, p->designated_root = bpdu->root; WRITE_ONCE(p->designated_cost, bpdu->root_path_cost); p->designated_bridge = bpdu->bridge_id; - p->designated_port = bpdu->port_id; + WRITE_ONCE(p->designated_port, bpdu->port_id); p->designated_age = jiffies - bpdu->message_age; mod_timer(&p->message_age_timer, jiffies @@ -432,7 +432,7 @@ void br_become_designated_port(struct net_bridge_port *p) p->designated_root = br->designated_root; WRITE_ONCE(p->designated_cost, br->root_path_cost); p->designated_bridge = br->bridge_id; - p->designated_port = p->port_id; + WRITE_ONCE(p->designated_port, p->port_id); } diff --git a/net/bridge/br_stp_if.c b/net/bridge/br_stp_if.c index e5d43492d2dcf0615ee984bc190d7ce2264aaab0..7b0d1a334785047905a00694fd65e3212b160e5d 100644 --- a/net/bridge/br_stp_if.c +++ b/net/bridge/br_stp_if.c @@ -320,7 +320,7 @@ int br_stp_set_port_priority(struct net_bridge_port *p, unsigned long newprio) new_port_id = br_make_port_id(newprio, p->port_no); if (br_is_designated_port(p)) - p->designated_port = new_port_id; + WRITE_ONCE(p->designated_port, new_port_id); p->port_id = new_port_id; p->priority = newprio; diff --git a/net/bridge/br_sysfs_if.c b/net/bridge/br_sysfs_if.c index 36b832902d33a492e91d53a4248778b3ee2322ca..1023f97b1c9a22a1f79c3c734aef9bd41832ea39 100644 --- a/net/bridge/br_sysfs_if.c +++ b/net/bridge/br_sysfs_if.c @@ -129,7 +129,7 @@ static BRPORT_ATTR(designated_bridge, 0444, show_designated_bridge, NULL); static ssize_t show_designated_port(struct net_bridge_port *p, char *buf) { - return sysfs_emit(buf, "%d\n", p->designated_port); + return sysfs_emit(buf, "%d\n", READ_ONCE(p->designated_port)); } static BRPORT_ATTR(designated_port, 0444, show_designated_port, NULL); -- 2.54.0.1013.g208068f2d8-goog