[PATCH 004 of 8] knfsd: rpcgss : RPC_GSS_PROC_ DESTROY request will get a bad rpc

[NeilBrown <neilb@suse.de>]

From: Wei Yongjun <yjwei@cn.fujitsu.com>


If I send a RPC_GSS_PROC_DESTROY message to NFSv4 server, it will reply
with a bad rpc reply which lacks an authentication verifier.
Maybe this patch is needed.

Send/recv packets as following:

send:

RemoteProcedureCall
    xid
    rpcvers = 2
    prog = 100003
    vers = 4
    proc = 0
    cred = AUTH_GSS
        version = 1
        gss_proc = 3 (RPCSEC_GSS_DESTROY)
        service  = 1 (RPC_GSS_SVC_NONE)
    verf = AUTH_GSS
        checksum

reply:

RemoteProcedureReply
    xid
    msg_type
    reply_stat
    accepted_reply

Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: "J. Bruce Fields" <bfields@citi.umich.edu>
Signed-off-by: Neil Brown <neilb@suse.de>

### Diffstat output
 ./net/sunrpc/auth_gss/svcauth_gss.c |    2 ++
 1 file changed, 2 insertions(+)

diff .prev/net/sunrpc/auth_gss/svcauth_gss.c ./net/sunrpc/auth_gss/svcauth_gss.c
--- .prev/net/sunrpc/auth_gss/svcauth_gss.c	2007-05-07 10:31:03.000000000 +1000
+++ ./net/sunrpc/auth_gss/svcauth_gss.c	2007-05-07 10:31:04.000000000 +1000
@@ -1106,6 +1106,8 @@ svcauth_gss_accept(struct svc_rqst *rqst
 		}
 		goto complete;
 	case RPC_GSS_PROC_DESTROY:
+		if (gss_write_verf(rqstp, rsci->mechctx, gc->gc_seq))
+			goto auth_err;
 		set_bit(CACHE_NEGATIVE, &rsci->h.flags);
 		if (resv->iov_len + 4 > PAGE_SIZE)
 			goto drop;