4.19-stable review patch. If anyone has any objections, please let me know.
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From: Nikolay Aleksandrov nikolay@cumulusnetworks.com
[ Upstream commit 435f2e7cc0b783615d7fbcf08f5f00d289f9caeb ]
Add support for entries which are "sticky", i.e. will not change their port if they show up from a different one. A new ndm flag is introduced for that purpose - NTF_STICKY. We allow to set it only to non-local entries.
Signed-off-by: Nikolay Aleksandrov nikolay@cumulusnetworks.com Signed-off-by: David S. Miller davem@davemloft.net Stable-dep-of: bee2ef946d31 ("net: bridge: br_fdb_external_learn_add(): always set EXT_LEARN") Signed-off-by: Sasha Levin sashal@kernel.org --- include/uapi/linux/neighbour.h | 1 + net/bridge/br_fdb.c | 19 ++++++++++++++++--- net/bridge/br_private.h | 1 + 3 files changed, 18 insertions(+), 3 deletions(-)
diff --git a/include/uapi/linux/neighbour.h b/include/uapi/linux/neighbour.h index 904db6148476..998155444e0d 100644 --- a/include/uapi/linux/neighbour.h +++ b/include/uapi/linux/neighbour.h @@ -43,6 +43,7 @@ enum { #define NTF_PROXY 0x08 /* == ATF_PUBL */ #define NTF_EXT_LEARNED 0x10 #define NTF_OFFLOADED 0x20 +#define NTF_STICKY 0x40 #define NTF_ROUTER 0x80
/* diff --git a/net/bridge/br_fdb.c b/net/bridge/br_fdb.c index 4d4b9b5ea1c1..1714f4e91fca 100644 --- a/net/bridge/br_fdb.c +++ b/net/bridge/br_fdb.c @@ -584,7 +584,7 @@ void br_fdb_update(struct net_bridge *br, struct net_bridge_port *source, unsigned long now = jiffies;
/* fastpath: update of existing entry */ - if (unlikely(source != fdb->dst)) { + if (unlikely(source != fdb->dst && !fdb->is_sticky)) { fdb->dst = source; fdb_modified = true; /* Take over HW learned entry */ @@ -656,6 +656,8 @@ static int fdb_fill_info(struct sk_buff *skb, const struct net_bridge *br, ndm->ndm_flags |= NTF_OFFLOADED; if (fdb->added_by_external_learn) ndm->ndm_flags |= NTF_EXT_LEARNED; + if (fdb->is_sticky) + ndm->ndm_flags |= NTF_STICKY;
if (nla_put(skb, NDA_LLADDR, ETH_ALEN, &fdb->key.addr)) goto nla_put_failure; @@ -772,8 +774,10 @@ int br_fdb_dump(struct sk_buff *skb,
/* Update (create or replace) forwarding database entry */ static int fdb_add_entry(struct net_bridge *br, struct net_bridge_port *source, - const __u8 *addr, __u16 state, __u16 flags, __u16 vid) + const u8 *addr, u16 state, u16 flags, u16 vid, + u8 ndm_flags) { + u8 is_sticky = !!(ndm_flags & NTF_STICKY); struct net_bridge_fdb_entry *fdb; bool modified = false;
@@ -789,6 +793,9 @@ static int fdb_add_entry(struct net_bridge *br, struct net_bridge_port *source, return -EINVAL; }
+ if (is_sticky && (state & NUD_PERMANENT)) + return -EINVAL; + fdb = br_fdb_find(br, addr, vid); if (fdb == NULL) { if (!(flags & NLM_F_CREATE)) @@ -832,6 +839,12 @@ static int fdb_add_entry(struct net_bridge *br, struct net_bridge_port *source,
modified = true; } + + if (is_sticky != fdb->is_sticky) { + fdb->is_sticky = is_sticky; + modified = true; + } + fdb->added_by_user = 1;
fdb->used = jiffies; @@ -865,7 +878,7 @@ static int __br_fdb_add(struct ndmsg *ndm, struct net_bridge *br, } else { spin_lock_bh(&br->hash_lock); err = fdb_add_entry(br, p, addr, ndm->ndm_state, - nlh_flags, vid); + nlh_flags, vid, ndm->ndm_flags); spin_unlock_bh(&br->hash_lock); }
diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h index 7ca3b469242e..4e0c6f9d9c16 100644 --- a/net/bridge/br_private.h +++ b/net/bridge/br_private.h @@ -181,6 +181,7 @@ struct net_bridge_fdb_entry { struct hlist_node fdb_node; unsigned char is_local:1, is_static:1, + is_sticky:1, added_by_user:1, added_by_external_learn:1, offloaded:1;