From: Chuck Lever <chuck.lever@xxxxxxxxxx>
Done as part of hardening the server-side RPC header encoding path.
Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx>
---
net/sunrpc/auth_gss/svcauth_gss.c | 81 ++++---------------------------------
1 file changed, 8 insertions(+), 73 deletions(-)
diff --git a/net/sunrpc/auth_gss/svcauth_gss.c b/net/sunrpc/auth_gss/svcauth_gss.c
index 9f3633c42ebd..89333669af26 100644
--- a/net/sunrpc/auth_gss/svcauth_gss.c
+++ b/net/sunrpc/auth_gss/svcauth_gss.c
@@ -693,28 +693,6 @@ static bool gss_check_seq_num(const struct svc_rqst *rqstp, struct rsc *rsci,
goto out;
}
-static inline u32 round_up_to_quad(u32 i)
-{
- return (i + 3 ) & ~3;
-}
-
-static inline int
-svc_safe_putnetobj(struct kvec *resv, struct xdr_netobj *o)
-{
- u8 *p;
-
- if (resv->iov_len + 4 > PAGE_SIZE)
- return -1;
- svc_putnl(resv, o->len);
- p = resv->iov_base + resv->iov_len;
- resv->iov_len += round_up_to_quad(o->len);
- if (resv->iov_len > PAGE_SIZE)
- return -1;
- memcpy(p, o->data, o->len);
- memset(p + o->len, 0, round_up_to_quad(o->len) - o->len);
- return 0;
-}
-
/*
* Decode and verify a Call's verifier field. For RPC_AUTH_GSS Calls,
* the body of this field contains a variable length checksum.
@@ -772,42 +750,6 @@ svcauth_gss_verify_header(struct svc_rqst *rqstp, struct rsc *rsci,
return SVC_OK;
}
-static int
-gss_write_verf(struct svc_rqst *rqstp, struct gss_ctx *ctx_id, u32 seq)
-{
- __be32 *xdr_seq;
- u32 maj_stat;
- struct xdr_buf verf_data;
- struct xdr_netobj mic;
- __be32 *p;
- struct kvec iov;
- int err = -1;
-
- svc_putnl(rqstp->rq_res.head, RPC_AUTH_GSS);
- xdr_seq = kmalloc(4, GFP_KERNEL);
- if (!xdr_seq)
- return -ENOMEM;
- *xdr_seq = htonl(seq);
-
- iov.iov_base = xdr_seq;
- iov.iov_len = 4;
- xdr_buf_from_iov(&iov, &verf_data);
- p = rqstp->rq_res.head->iov_base + rqstp->rq_res.head->iov_len;
- mic.data = (u8 *)(p + 1);
- maj_stat = gss_get_mic(ctx_id, &verf_data, &mic);
- if (maj_stat != GSS_S_COMPLETE)
- goto out;
- *p++ = htonl(mic.len);
- memset((u8 *)p + mic.len, 0, round_up_to_quad(mic.len) - mic.len);
- p += XDR_QUADLEN(mic.len);
- if (!xdr_ressize_check(rqstp, p))
- goto out;
- err = 0;
-out:
- kfree(xdr_seq);
- return err;
-}
-
/*
* Construct and encode a Reply's verifier field. The verifier's body
* field contains a variable-length checksum of the GSS sequence
@@ -1454,8 +1396,6 @@ svcauth_gss_proc_init(struct svc_rqst *rqstp, struct rpc_gss_wire_cred *gc)
u32 flavor, len;
void *body;
- svcxdr_init_encode(rqstp);
-
/* Call's verf field: */
if (xdr_stream_decode_opaque_auth(xdr, &flavor, &body, &len) < 0)
return SVC_GARBAGE;
@@ -1642,15 +1582,15 @@ svcauth_gss_decode_credbody(struct xdr_stream *xdr,
static int
svcauth_gss_accept(struct svc_rqst *rqstp)
{
- struct kvec *resv = &rqstp->rq_res.head[0];
struct gss_svc_data *svcdata = rqstp->rq_auth_data;
__be32 *rpcstart;
struct rpc_gss_wire_cred *gc;
struct rsc *rsci = NULL;
- __be32 *reject_stat = resv->iov_base + resv->iov_len;
int ret;
struct sunrpc_net *sn = net_generic(SVC_NET(rqstp), sunrpc_net_id);
+ svcxdr_init_encode(rqstp);
+
rqstp->rq_auth_stat = rpc_autherr_badcred;
if (!svcdata)
svcdata = kmalloc(sizeof(*svcdata), GFP_KERNEL);
@@ -1700,28 +1640,25 @@ svcauth_gss_accept(struct svc_rqst *rqstp)
/* now act upon the command: */
switch (gc->gc_proc) {
case RPC_GSS_PROC_DESTROY:
- if (gss_write_verf(rqstp, rsci->mechctx, gc->gc_seq))
+ if (!svcauth_gss_encode_verf(rqstp, rsci->mechctx, gc->gc_seq))
goto auth_err;
/* Delete the entry from the cache_list and call cache_put */
sunrpc_cache_unhash(sn->rsc_cache, &rsci->h);
- if (resv->iov_len + 4 > PAGE_SIZE)
- goto drop;
- svc_putnl(resv, RPC_SUCCESS);
+ if (xdr_stream_encode_u32(&rqstp->rq_res_stream, RPC_SUCCESS) < 0)
+ goto auth_err;
goto complete;
case RPC_GSS_PROC_DATA:
rqstp->rq_auth_stat = rpcsec_gsserr_ctxproblem;
- svcdata->verf_start = resv->iov_base + resv->iov_len;
- if (gss_write_verf(rqstp, rsci->mechctx, gc->gc_seq))
+ svcdata->verf_start = xdr_reserve_space(&rqstp->rq_res_stream, 0);
+ if (!svcauth_gss_encode_verf(rqstp, rsci->mechctx, gc->gc_seq))
goto auth_err;
rqstp->rq_cred = rsci->cred;
get_group_info(rsci->cred.cr_group_info);
rqstp->rq_auth_stat = rpc_autherr_badcred;
switch (gc->gc_svc) {
case RPC_GSS_SVC_NONE:
- svcxdr_init_encode(rqstp);
break;
case RPC_GSS_SVC_INTEGRITY:
- svcxdr_init_encode(rqstp);
/* placeholders for body length and seq. number: */
xdr_reserve_space(&rqstp->rq_res_stream, XDR_UNIT * 2);
if (svcauth_gss_unwrap_integ(rqstp, gc->gc_seq,
@@ -1730,7 +1667,6 @@ svcauth_gss_accept(struct svc_rqst *rqstp)
svcxdr_set_auth_slack(rqstp, RPC_MAX_AUTH_SIZE);
break;
case RPC_GSS_SVC_PRIVACY:
- svcxdr_init_encode(rqstp);
/* placeholders for body length and seq. number: */
xdr_reserve_space(&rqstp->rq_res_stream, XDR_UNIT * 2);
if (svcauth_gss_unwrap_priv(rqstp, gc->gc_seq,
@@ -1755,8 +1691,7 @@ svcauth_gss_accept(struct svc_rqst *rqstp)
ret = SVC_GARBAGE;
goto out;
auth_err:
- /* Restore write pointer to its original value: */
- xdr_ressize_check(rqstp, reject_stat);
+ xdr_truncate_encode(&rqstp->rq_res_stream, XDR_UNIT * 2);
ret = SVC_DENIED;
goto out;
complete:
