From: Chuck Lever <chuck.lever@xxxxxxxxxx>
Done as part of hardening the server-side RPC header decoding path.
Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx>
---
net/sunrpc/auth_gss/svcauth_gss.c | 25 ++++++++++++-------------
1 file changed, 12 insertions(+), 13 deletions(-)
diff --git a/net/sunrpc/auth_gss/svcauth_gss.c b/net/sunrpc/auth_gss/svcauth_gss.c
index 6aefe24953fa..3715ff842ca1 100644
--- a/net/sunrpc/auth_gss/svcauth_gss.c
+++ b/net/sunrpc/auth_gss/svcauth_gss.c
@@ -1778,40 +1778,39 @@ svcauth_gss_prepare_to_wrap(struct xdr_buf *resbuf, struct gss_svc_data *gsd)
static int svcauth_gss_wrap_integ(struct svc_rqst *rqstp)
{
struct gss_svc_data *gsd = rqstp->rq_auth_data;
+ struct xdr_stream *xdr = &rqstp->rq_res_stream;
struct rpc_gss_wire_cred *gc = &gsd->clcred;
- struct xdr_buf *buf = &rqstp->rq_res;
+ struct xdr_buf *buf = xdr->buf;
struct xdr_buf databody_integ;
struct xdr_netobj checksum;
u32 offset, len, maj_stat;
- struct kvec *resv;
__be32 *p;
p = svcauth_gss_prepare_to_wrap(buf, gsd);
if (p == NULL)
goto out;
+
offset = (u8 *)(p + 1) - (u8 *)buf->head[0].iov_base;
len = buf->len - offset;
- if (len & 3)
- goto out;
- *p++ = htonl(len);
- *p++ = htonl(gc->gc_seq);
if (xdr_buf_subsegment(buf, &databody_integ, offset, len))
goto wrap_failed;
+ /* Buffer space for these has already been reserved in
+ * svcauth_gss_accept(). */
+ *p++ = cpu_to_be32(len);
+ *p = cpu_to_be32(gc->gc_seq);
checksum.data = gsd->gsd_scratch;
maj_stat = gss_get_mic(gsd->rsci->mechctx, &databody_integ, &checksum);
if (maj_stat != GSS_S_COMPLETE)
goto bad_mic;
- svc_putnl(resv, checksum.len);
- memset(checksum.data + checksum.len, 0,
- round_up_to_quad(checksum.len) - checksum.len);
- resv->iov_len += XDR_QUADLEN(checksum.len) << 2;
- /* not strictly required: */
- buf->len += XDR_QUADLEN(checksum.len) << 2;
- if (resv->iov_len > PAGE_SIZE)
+
+ if (xdr_stream_encode_opaque(xdr, checksum.data, checksum.len) < 0)
goto wrap_failed;
+ xdr_commit_encode(xdr);
+
out:
return 0;
+
bad_mic:
trace_rpcgss_svc_get_mic(rqstp, maj_stat);
wrap_failed:
