From: Olga Kornievskaia <kolga@netapp.com>
Date: Sun, 18 Jun 2023 17:32:25 -0400
Subject: [PATCH] NFSv4.1: freeze the session table upon receiving
 NFS4ERR_BADSESSION
Git-commit: c907e72f58ed979a24a9fdcadfbc447c51d5e509
Patch-mainline: v6.5
References: git-fixes

When the client received NFS4ERR_BADSESSION, it schedules recovery
and start the state manager thread which in turn freezes the
session table and does not allow for any new requests to use the
no-longer valid session. However, it is possible that before
the state manager thread runs, a new operation would use the
released slot that received BADSESSION and was therefore not
updated its sequence number. Such re-use of the slot can lead
the application errors.

Fixes: 5c441544f045 ("NFSv4.x: Handle bad/dead sessions correctly in nfs41_sequence_process()")
Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Acked-by: NeilBrown <neilb@suse.com>

---
 fs/nfs/nfs4proc.c |    1 +
 1 file changed, 1 insertion(+)

--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -923,6 +923,7 @@ out:
 out_noaction:
 	return ret;
 session_recover:
+	set_bit(NFS4_SLOT_TBL_DRAINING, &session->fc_slot_table.slot_tbl_state);
 	nfs4_schedule_session_recovery(session, status);
 	dprintk("%s ERROR: %d Reset session\n", __func__, status);
 	nfs41_sequence_free_slot(res);