Re: [PATCH] SUNRPC: Don't create a gss auth cache unless rpc.gssd is running

[Steve Dickson <SteveD@redhat.com>]

On 02/10/2014 06:01 PM, Steve Dickson wrote:
> 
> 
> On 02/10/2014 04:48 PM, Trond Myklebust wrote:
>> An infinite loop is caused when nfs4_establish_lease() fails
>> with -EACCES. This causes nfs4_handle_reclaim_lease_error()
>> to sleep a bit and resets the NFS4CLNT_LEASE_EXPIRED bit.
>> This in turn causes nfs4_state_manager() to try and
>> reestablished the lease, again, again, again...
>>
>> The problem is a valid RPCSEC_GSS client is being created when
>> rpc.gssd is not running.
>>
>> Link: http://lkml.kernel.org/r/1392066375-16502-1-git-send-email-steved@redhat.com
>> Fixes: 0ea9de0ea6a4 (sunrpc: turn warn_gssd() log message into a dprintk())
>> Reported-by: Steve Dickson <steved@redhat.com>
>> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
>> ---
>>  net/sunrpc/auth_gss/auth_gss.c | 2 ++
>>  1 file changed, 2 insertions(+)
>>
>> diff --git a/net/sunrpc/auth_gss/auth_gss.c b/net/sunrpc/auth_gss/auth_gss.c
>> index 6c0513a7f992..44a61e8fda6f 100644
>> --- a/net/sunrpc/auth_gss/auth_gss.c
>> +++ b/net/sunrpc/auth_gss/auth_gss.c
>> @@ -991,6 +991,8 @@ gss_create_new(struct rpc_auth_create_args *args, struct rpc_clnt *clnt)
>>  	gss_auth->service = gss_pseudoflavor_to_service(gss_auth->mech, flavor);
>>  	if (gss_auth->service == 0)
>>  		goto err_put_mech;
>> +	if (!gssd_running(gss_auth->net))
>> +		goto err_put_mech;
>>  	auth = &gss_auth->rpc_auth;
>>  	auth->au_cslack = GSS_CRED_SLACK >> 2;
>>  	auth->au_rslack = GSS_VERF_SLACK >> 2;
>>
> Unfortunately I'm seeing the same loop but this time its with _nfs4_proc_exchange_id
> 
> Here is the trace point output:
>   192.168.62.8-ma-20371 [000] .... 955443.604229: nfs4_exchange_id: error=-13 (EACCES) dstaddr=192.168.62.8
> 
> and here is the rpcdebug output:
> [ 2782.341981] NFS call  exchange_id auth=RPCSEC_GSS, 'Linux NFSv4.1 <client>'
> [ 2782.360540] NFS reply exchange_id: -13
> 
> All three mounts (v4.0, v4.1, v4.2) are hung...
> 
> Looking into it...
Pilot error on my part... I only reloaded sunrpc.ko not auth_rpcgss.ko
What a good night sleep can do for you... :-) 

Tested-by: Steve Dickson <steved@redhat.com> 

Question, should we be checking that gssd still running when
gss_auth pointer is found in the hash table? I'm thinking 
of the case where gssd was started and then stopped. 

steved.