fdb->updated and fdb->used are read and written locklessly. Add READ_ONCE()/WRITE_ONCE() annotations. Fixes: 31cbc39b6344 ("net: bridge: add option to allow activity notifications for any fdb entries") Signed-off-by: Eric Dumazet Cc: Nikolay Aleksandrov --- v2: annotate all problematic fdb->updated and fdb->used reads/writes. v1: https://lore.kernel.org/netdev/CANn89iL8-e_jphcg49eX=zdWrOeuA-AJDL0qhsTrApA4YnOFEg@mail.gmail.com/T/#mf99b76469697813939abe745f42ace3e201ef6f4 net/bridge/br_fdb.c | 28 ++++++++++++++++------------ 1 file changed, 16 insertions(+), 12 deletions(-) diff --git a/net/bridge/br_fdb.c b/net/bridge/br_fdb.c index 58d22e2b85fc3551bd5aec9c20296ddfcecaa040..0501ffcb8a3ddb21a19254915564b4000b6b6911 100644 --- a/net/bridge/br_fdb.c +++ b/net/bridge/br_fdb.c @@ -70,7 +70,7 @@ static inline int has_expired(const struct net_bridge *br, { return !test_bit(BR_FDB_STATIC, &fdb->flags) && !test_bit(BR_FDB_ADDED_BY_EXT_LEARN, &fdb->flags) && - time_before_eq(fdb->updated + hold_time(br), jiffies); + time_before_eq(READ_ONCE(fdb->updated) + hold_time(br), jiffies); } static int fdb_to_nud(const struct net_bridge *br, @@ -126,9 +126,9 @@ static int fdb_fill_info(struct sk_buff *skb, const struct net_bridge *br, if (nla_put_u32(skb, NDA_FLAGS_EXT, ext_flags)) goto nla_put_failure; - ci.ndm_used = jiffies_to_clock_t(now - fdb->used); + ci.ndm_used = jiffies_to_clock_t(now - READ_ONCE(fdb->used)); ci.ndm_confirmed = 0; - ci.ndm_updated = jiffies_to_clock_t(now - fdb->updated); + ci.ndm_updated = jiffies_to_clock_t(now - READ_ONCE(fdb->updated)); ci.ndm_refcnt = 0; if (nla_put(skb, NDA_CACHEINFO, sizeof(ci), &ci)) goto nla_put_failure; @@ -551,7 +551,7 @@ void br_fdb_cleanup(struct work_struct *work) */ rcu_read_lock(); hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) { - unsigned long this_timer = f->updated + delay; + unsigned long this_timer = READ_ONCE(f->updated) + delay; if (test_bit(BR_FDB_STATIC, &f->flags) || test_bit(BR_FDB_ADDED_BY_EXT_LEARN, &f->flags)) { @@ -924,6 +924,7 @@ int br_fdb_fillbuf(struct net_bridge *br, void *buf, { struct net_bridge_fdb_entry *f; struct __fdb_entry *fe = buf; + unsigned long delta; int num = 0; memset(buf, 0, maxnum*sizeof(struct __fdb_entry)); @@ -953,8 +954,11 @@ int br_fdb_fillbuf(struct net_bridge *br, void *buf, fe->port_hi = f->dst->port_no >> 8; fe->is_local = test_bit(BR_FDB_LOCAL, &f->flags); - if (!test_bit(BR_FDB_STATIC, &f->flags)) - fe->ageing_timer_value = jiffies_delta_to_clock_t(jiffies - f->updated); + if (!test_bit(BR_FDB_STATIC, &f->flags)) { + delta = jiffies - READ_ONCE(f->updated); + fe->ageing_timer_value = + jiffies_delta_to_clock_t(delta); + } ++fe; ++num; } @@ -1002,8 +1006,8 @@ void br_fdb_update(struct net_bridge *br, struct net_bridge_port *source, unsigned long now = jiffies; bool fdb_modified = false; - if (now != fdb->updated) { - fdb->updated = now; + if (now != READ_ONCE(fdb->updated)) { + WRITE_ONCE(fdb->updated, now); fdb_modified = __fdb_mark_active(fdb); } @@ -1242,10 +1246,10 @@ static int fdb_add_entry(struct net_bridge *br, struct net_bridge_port *source, if (fdb_handle_notify(fdb, notify)) modified = true; - fdb->used = jiffies; + WRITE_ONCE(fdb->used, jiffies); if (modified) { if (refresh) - fdb->updated = jiffies; + WRITE_ONCE(fdb->updated, jiffies); fdb_notify(br, fdb, RTM_NEWNEIGH, true); } @@ -1556,7 +1560,7 @@ int br_fdb_external_learn_add(struct net_bridge *br, struct net_bridge_port *p, goto err_unlock; } - fdb->updated = jiffies; + WRITE_ONCE(fdb->updated, jiffies); if (READ_ONCE(fdb->dst) != p) { WRITE_ONCE(fdb->dst, p); @@ -1565,7 +1569,7 @@ int br_fdb_external_learn_add(struct net_bridge *br, struct net_bridge_port *p, if (test_and_set_bit(BR_FDB_ADDED_BY_EXT_LEARN, &fdb->flags)) { /* Refresh entry */ - fdb->used = jiffies; + WRITE_ONCE(fdb->used, jiffies); } else { modified = true; } -- 2.52.0.351.gbe84eed79e-goog