[PATCH 002 of 9] knfsd: svcrpc: gss: fix failure on SVC_DENIED in integrity case

NeilBrown
2006-09-04T23:16:04Z

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>

### Diffstat output
./net/sunrpc/auth_gss/svcauth_gss.c | 30 ++++++++++++++++++------------
1 file changed, 18 insertions(+), 12 deletions(-)

diff .prev/net/sunrpc/auth_gss/svcauth_gss.c ./net/sunrpc/auth_gss/svcauth_gss.c
--- .prev/net/sunrpc/auth_gss/svcauth_gss.c 2006-09-04 17:12:31.000000000 +1000
+++ ./net/sunrpc/auth_gss/svcauth_gss.c 2006-09-04 17:13:17.000000000 +1000
@@ -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: */
- u32 *body_start;
+ /* save a pointer to the beginning of the encoded verifier,
+ * for use in encryption/checksumming in svcauth_gss_release: */
+ u32 *verf_start;
struct rsc *rsci;
};

@@ -968,7 +968,7 @@ svcauth_gss_accept(struct svc_rqst *rqst
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 *rqst
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 *rqst
gc->gc_seq, rsci->mechctx))
goto auth_err;
/* placeholders for length and seq. number: */
- svcdata->body_start = resv->iov_base + resv->iov_len;
svc_putu32(resv, 0);
svc_putu32(resv, 0);
break;
@@ -1119,7 +1119,6 @@ svcauth_gss_accept(struct svc_rqst *rqst
gc->gc_seq, rsci->mechctx))
goto auth_err;
/* placeholders for length and seq. number: */
- svcdata->body_start = resv->iov_base + resv->iov_len;
svc_putu32(resv, 0);
svc_putu32(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->verf_start;
+ gsd->verf_start = NULL;

- p = gsd->body_start;
- gsd->body_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 *rqs
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