This is a note to let you know that I've just added the patch titled fs: dlm: send FIN ack back in right cases to the 5.15-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: fs-dlm-send-fin-ack-back-in-right-cases.patch and it can be found in the queue-5.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 00908b3388255fc1d3782b744d07f327712f401f Mon Sep 17 00:00:00 2001 From: Alexander Aring <aahringo@xxxxxxxxxx> Date: Thu, 12 Jan 2023 17:10:37 -0500 Subject: fs: dlm: send FIN ack back in right cases 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 @@ -366,7 +366,7 @@ 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; @@ -478,15 +478,14 @@ 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)); @@ -503,12 +502,14 @@ 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)); Patches currently in stable-queue which might be from aahringo@xxxxxxxxxx are queue-5.15/fs-dlm-send-fin-ack-back-in-right-cases.patch queue-5.15/fs-dlm-move-sending-fin-message-into-state-change-handling.patch queue-5.15/fs-dlm-don-t-set-stop-rx-flag-after-node-reset.patch