[PATCH] knfsd: svcrpc: gss: fix failure on SVC_DENIED in integrity case

If the request is denied after gss_accept was called, we shouldn't try to wrap
the reply.  We were checking the accept_stat but not the reply_stat.

To check the reply_stat in _release, we need a pointer to before (rather than
after) the verifier, so modify body_start appropriately.

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 18 insertions, 12 deletions

diff --git a/net/sunrpc/auth_gss/svcauth_gss.c b/net/sunrpc/auth_gss/svcauth_gss.c
index eeb1cce96649..447d9aef4605 100644
--- a/net/sunrpc/auth_gss/svcauth_gss.c
+++ b/net/sunrpc/auth_gss/svcauth_gss.c
@@ -903,9 +903,9 @@ out_seq:
 struct gss_svc_data {
         /* decoded gss client cred: */
         struct rpc_gss_wire_cred        clcred;
-        /* pointer to the beginning of the procedure-specific results,
-         * which may be encrypted/checksummed in svcauth_gss_release: */
-        __be32                          *body_start;
+        /* save a pointer to the beginning of the encoded verifier,
+         * for use in encryption/checksumming in svcauth_gss_release: */
+        __be32                          *verf_start;
         struct rsc                      *rsci;
 };
 
@@ -968,7 +968,7 @@ svcauth_gss_accept(struct svc_rqst *rqstp, __be32 *authp)
         if (!svcdata)
                 goto auth_err;
         rqstp->rq_auth_data = svcdata;
-        svcdata->body_start = NULL;
+        svcdata->verf_start = NULL;
         svcdata->rsci = NULL;
         gc = &svcdata->clcred;
 
@@ -1097,6 +1097,7 @@ svcauth_gss_accept(struct svc_rqst *rqstp, __be32 *authp)
                 goto complete;
         case RPC_GSS_PROC_DATA:
                 *authp = rpcsec_gsserr_ctxproblem;
+                svcdata->verf_start = resv->iov_base + resv->iov_len;
                 if (gss_write_verf(rqstp, rsci->mechctx, gc->gc_seq))
                         goto auth_err;
                 rqstp->rq_cred = rsci->cred;
@@ -1110,7 +1111,6 @@ svcauth_gss_accept(struct svc_rqst *rqstp, __be32 *authp)
                                         gc->gc_seq, rsci->mechctx))
                                 goto auth_err;
                         /* placeholders for length and seq. number: */
-                        svcdata->body_start = resv->iov_base + resv->iov_len;
                         svc_putnl(resv, 0);
                         svc_putnl(resv, 0);
                         break;
@@ -1119,7 +1119,6 @@ svcauth_gss_accept(struct svc_rqst *rqstp, __be32 *authp)
                                         gc->gc_seq, rsci->mechctx))
                                 goto auth_err;
                         /* placeholders for length and seq. number: */
-                        svcdata->body_start = resv->iov_base + resv->iov_len;
                         svc_putnl(resv, 0);
                         svc_putnl(resv, 0);
                         break;
@@ -1150,14 +1149,21 @@ out:
 u32 *
 svcauth_gss_prepare_to_wrap(struct xdr_buf *resbuf, struct gss_svc_data *gsd)
 {
-        u32 *p;
+        u32 *p, verf_len;
 
-        p = gsd->body_start;
-        gsd->body_start = NULL;
+        p = gsd->verf_start;
+        gsd->verf_start = NULL;
+
+        /* If the reply stat is nonzero, don't wrap: */
+        if (*(p-1) != rpc_success)
+                return NULL;
+        /* Skip the verifier: */
+        p += 1;
+        verf_len = ntohl(*p++);
+        p += XDR_QUADLEN(verf_len);
         /* move accept_stat to right place: */
         memcpy(p, p + 2, 4);
-        /* Don't wrap in failure case: */
-        /* Counting on not getting here if call was not even accepted! */
+        /* Also don't wrap if the accept stat is nonzero: */
         if (*p != rpc_success) {
                 resbuf->head[0].iov_len -= 2 * 4;
                 return NULL;
@@ -1283,7 +1289,7 @@ svcauth_gss_release(struct svc_rqst *rqstp)
         if (gc->gc_proc != RPC_GSS_PROC_DATA)
                 goto out;
         /* Release can be called twice, but we only wrap once. */
-        if (gsd->body_start == NULL)
+        if (gsd->verf_start == NULL)
                 goto out;
         /* normally not set till svc_send, but we need it here: */
         /* XXX: what for?  Do we mess it up the moment we call svc_putu32