[PATCH 4.10 46/81] NFSv4.1 fix infinite loop on IO BAD_STATEID error

Greg Kroah-Hartman
2017-04-06T09:00:12Z

From: Olga Kornievskaia <kolga@netapp.com>

commit 0e3d3e5df07dcf8a50d96e0ecd6ab9a888f55dfc upstream.

Commit 63d63cbf5e03 "NFSv4.1: Don't recheck delegations that
have already been checked" introduced a regression where when a
client received BAD_STATEID error it would not send any TEST_STATEID
and instead go into an infinite loop of resending the IO that caused
the BAD_STATEID.

Fixes: 63d63cbf5e03 ("NFSv4.1: Don't recheck delegations that have already been checked")
Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
fs/nfs/nfs4proc.c | 9 +++------
1 file changed, 3 insertions(+), 6 deletions(-)

--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -2550,17 +2550,14 @@ static void nfs41_check_delegation_state
}

nfs4_stateid_copy(&stateid, &delegation->stateid);
- if (test_bit(NFS_DELEGATION_REVOKED, &delegation->flags)) {
+ if (test_bit(NFS_DELEGATION_REVOKED, &delegation->flags) ||
+ !test_and_clear_bit(NFS_DELEGATION_TEST_EXPIRED,
+ &delegation->flags)) {
rcu_read_unlock();
nfs_finish_clear_delegation_stateid(state, &stateid);
return;
}

- if (!test_and_clear_bit(NFS_DELEGATION_TEST_EXPIRED, &delegation->flags)) {
- rcu_read_unlock();
- return;
- }
-
cred = get_rpccred(delegation->cred);
rcu_read_unlock();
status = nfs41_test_and_free_expired_stateid(server, &stateid, cred);