From: Tung Nguyen tung.q.nguyen@dektech.com.au
[ Upstream commit c244c092f1ed2acfb5af3d3da81e22367d3dd733 ]
This unexpected behavior is observed:
node 1 | node 2 ------ | ------ link is established | link is established reboot | link is reset up | send discovery message receive discovery message | link is established | link is established send discovery message | | receive discovery message | link is reset (unexpected) | send reset message link is reset |
It is due to delayed re-discovery as described in function tipc_node_check_dest(): "this link endpoint has already reset and re-established contact with the peer, before receiving a discovery message from that node."
However, commit 598411d70f85 has changed the condition for calling tipc_node_link_down() which was the acceptance of new media address.
This commit fixes this by restoring the old and correct behavior.
Fixes: 598411d70f85 ("tipc: make resetting of links non-atomic") Acked-by: Jon Maloy jmaloy@redhat.com Signed-off-by: Tung Nguyen tung.q.nguyen@dektech.com.au Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- net/tipc/node.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-)
diff --git a/net/tipc/node.c b/net/tipc/node.c index 7589f2ac6fd0..38f61dccb855 100644 --- a/net/tipc/node.c +++ b/net/tipc/node.c @@ -1152,8 +1152,9 @@ void tipc_node_check_dest(struct net *net, u32 addr, bool addr_match = false; bool sign_match = false; bool link_up = false; + bool link_is_reset = false; bool accept_addr = false; - bool reset = true; + bool reset = false; char *if_name; unsigned long intv; u16 session; @@ -1173,14 +1174,14 @@ void tipc_node_check_dest(struct net *net, u32 addr, /* Prepare to validate requesting node's signature and media address */ l = le->link; link_up = l && tipc_link_is_up(l); + link_is_reset = l && tipc_link_is_reset(l); addr_match = l && !memcmp(&le->maddr, maddr, sizeof(*maddr)); sign_match = (signature == n->signature);
/* These three flags give us eight permutations: */
if (sign_match && addr_match && link_up) { - /* All is fine. Do nothing. */ - reset = false; + /* All is fine. Ignore requests. */ /* Peer node is not a container/local namespace */ if (!n->peer_hash_mix) n->peer_hash_mix = hash_mixes; @@ -1205,6 +1206,7 @@ void tipc_node_check_dest(struct net *net, u32 addr, */ accept_addr = true; *respond = true; + reset = true; } else if (!sign_match && addr_match && link_up) { /* Peer node rebooted. Two possibilities: * - Delayed re-discovery; this link endpoint has already @@ -1236,6 +1238,7 @@ void tipc_node_check_dest(struct net *net, u32 addr, n->signature = signature; accept_addr = true; *respond = true; + reset = true; }
if (!accept_addr) @@ -1264,6 +1267,7 @@ void tipc_node_check_dest(struct net *net, u32 addr, tipc_link_fsm_evt(l, LINK_RESET_EVT); if (n->state == NODE_FAILINGOVER) tipc_link_fsm_evt(l, LINK_FAILOVER_BEGIN_EVT); + link_is_reset = tipc_link_is_reset(l); le->link = l; n->link_cnt++; tipc_node_calculate_timer(n, l); @@ -1276,7 +1280,7 @@ void tipc_node_check_dest(struct net *net, u32 addr, memcpy(&le->maddr, maddr, sizeof(*maddr)); exit: tipc_node_write_unlock(n); - if (reset && l && !tipc_link_is_reset(l)) + if (reset && !link_is_reset) tipc_node_link_down(n, b->identity, false); tipc_node_put(n); }