rpc/auth: Avoid NULL dereference in rpcsvc_auth_request_init()

Code section is bogus!
------------------------------------------
370:       if (!auth->authops->request_init)
371:              ret = auth->authops->request_init (req, auth->authprivate);
------------------------------------------

Seems to have been never been used historically since
logically above code has never been true to actually execute
"authops->request_init() --> auth_glusterfs_{v2,}_request_init()"

On top of that under "rpcsvc_request_init()"
verf.flavour and verf.datalen are initialized from what is
provided through 'callmsg'.
------------------------------------------
        req->verf.flavour = rpc_call_verf_flavour (callmsg);
        req->verf.datalen = rpc_call_verf_len (callmsg);

        /* AUTH */
        rpcsvc_auth_request_init (req);
        return req;
------------------------------------------

So the code in 'auth_glusterfs_{v2,}_request_init()'
performing this operation will over-write the original
flavour and datalen.

------------------------------------------
      if (!req)
                return -1;
        memset (req->verf.authdata, 0, GF_MAX_AUTH_BYTES);
        req->verf.datalen = 0;
        req->verf.flavour = AUTH_NULL;
------------------------------------------

Refactoring the whole code into a more understandable version
and also avoiding a potential NULL dereference

Change-Id: I1a430fcb4d26de8de219bd0cb3c46c141649d47d
BUG: 1049735
Signed-off-by: Harshavardhana <harsha@harshavardhana.net>
Reviewed-on: http://review.gluster.org/6591
Reviewed-by: Santosh Pradhan <spradhan@redhat.com>
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Vijay Bellur <vbellur@redhat.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/rpc/rpc-lib/src/rpcsvc.h b/rpc/rpc-lib/src/rpcsvc.h
index 28ec93e11..30a969b11 100644
--- a/rpc/rpc-lib/src/rpcsvc.h
+++ b/rpc/rpc-lib/src/rpcsvc.h
@@ -553,7 +553,7 @@ struct rpcsvc_auth_list {
 };
 
 extern int
-rpcsvc_auth_request_init (rpcsvc_request_t *req);
+rpcsvc_auth_request_init (rpcsvc_request_t *req, struct rpc_msg *callmsg);
 
 extern int
 rpcsvc_auth_init (rpcsvc_t *svc, dict_t *options);