From: Alexander Aring <aahringo@xxxxxxxxxx> commit 00908b3388255fc1d3782b744d07f327712f401f upstream. This patch moves to send a ack back for receiving a FIN message only when we are in valid states. In other cases and there might be a sender waiting for a ack we just let it timeout at the senders time and hopefully all other cleanups will remove the FIN message on their sending queue. As an example we should never send out an ACK being in LAST_ACK state or we cannot assume a working socket communication when we are in CLOSED state. Cc: stable@xxxxxxxxxxxxxxx Fixes: 489d8e559c65 ("fs: dlm: add reliable connection if reconnect") Signed-off-by: Alexander Aring <aahringo@xxxxxxxxxx> Signed-off-by: David Teigland <teigland@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- fs/dlm/midcomms.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) --- a/fs/dlm/midcomms.c +++ b/fs/dlm/midcomms.c @@ -374,7 +374,7 @@ static int dlm_send_ack(int nodeid, uint struct dlm_msg *msg; char *ppc; - msg = dlm_lowcomms_new_msg(nodeid, mb_len, GFP_NOFS, &ppc, + msg = dlm_lowcomms_new_msg(nodeid, mb_len, GFP_ATOMIC, &ppc, NULL, NULL); if (!msg) return -ENOMEM; @@ -483,15 +483,14 @@ static void dlm_midcomms_receive_buffer( switch (p->header.h_cmd) { case DLM_FIN: - /* send ack before fin */ - dlm_send_ack(node->nodeid, node->seq_next); - spin_lock(&node->state_lock); pr_debug("receive fin msg from node %d with state %s\n", node->nodeid, dlm_state_str(node->state)); switch (node->state) { case DLM_ESTABLISHED: + dlm_send_ack(node->nodeid, node->seq_next); + node->state = DLM_CLOSE_WAIT; pr_debug("switch node %d to state %s\n", node->nodeid, dlm_state_str(node->state)); @@ -508,12 +507,14 @@ static void dlm_midcomms_receive_buffer( } break; case DLM_FIN_WAIT1: + dlm_send_ack(node->nodeid, node->seq_next); node->state = DLM_CLOSING; set_bit(DLM_NODE_FLAG_STOP_RX, &node->flags); pr_debug("switch node %d to state %s\n", node->nodeid, dlm_state_str(node->state)); break; case DLM_FIN_WAIT2: + dlm_send_ack(node->nodeid, node->seq_next); midcomms_node_reset(node); pr_debug("switch node %d to state %s\n", node->nodeid, dlm_state_str(node->state));