SUNRPC: Clean up svcauth_gss_accept's NULL procedure check

Micro-optimizations:

1. The value of rqstp->rq_auth_stat is replaced no matter which
   arm of the switch is taken, so the initial assignment can be
   safely removed.

2. Avoid checking the value of gc->gc_proc twice in the I/O
   (RPC_GSS_PROC_DATA) path.

The cost is a little extra code redundancy.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

diff --git a/net/sunrpc/auth_gss/svcauth_gss.c b/net/sunrpc/auth_gss/svcauth_gss.c
index ecd38d2bbf7a3affcef49e3dc4259b43bdc1e778..76d2e4e04d59a57b0b325e7fccad4fe4a72a20c3 100644 (file)
--- a/net/sunrpc/auth_gss/svcauth_gss.c
+++ b/net/sunrpc/auth_gss/svcauth_gss.c
@@ -1608,17 +1608,19 @@ svcauth_gss_accept(struct svc_rqst *rqstp)
        if (crlen != round_up_to_quad(gc->gc_ctx.len) + 5 * 4)
                goto auth_err;
 
-       if ((gc->gc_proc != RPC_GSS_PROC_DATA) && (rqstp->rq_proc != 0))
-               goto auth_err;
-
        svcxdr_init_decode(rqstp);
-       rqstp->rq_auth_stat = rpc_autherr_badverf;
+
        switch (gc->gc_proc) {
        case RPC_GSS_PROC_INIT:
        case RPC_GSS_PROC_CONTINUE_INIT:
+               if (rqstp->rq_proc != 0)
+                       goto auth_err;
                return svcauth_gss_proc_init(rqstp, gc);
-       case RPC_GSS_PROC_DATA:
        case RPC_GSS_PROC_DESTROY:
+               if (rqstp->rq_proc != 0)
+                       goto auth_err;
+               fallthrough;
+       case RPC_GSS_PROC_DATA:
                /* Look up the context, and check the verifier: */
                rqstp->rq_auth_stat = rpcsec_gsserr_credproblem;
                rsci = gss_svc_searchbyctx(sn->rsc_cache, &gc->gc_ctx);
@@ -1634,6 +1636,8 @@ svcauth_gss_accept(struct svc_rqst *rqstp)
                }
                break;
        default:
+               if (rqstp->rq_proc != 0)
+                       goto auth_err;
                rqstp->rq_auth_stat = rpc_autherr_rejectedcred;
                goto auth_err;
        }