As part of the update, open code that sanity-checks the size of the
data payload against the length of the RPC Call message has to be
re-implemented to use xdr_stream infrastructure.
Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx>
---
fs/nfsd/nfs3xdr.c | 56 +++++++++++++++++++++--------------------------------
1 file changed, 22 insertions(+), 34 deletions(-)
diff --git a/fs/nfsd/nfs3xdr.c b/fs/nfsd/nfs3xdr.c
index 2b51686c238f..38dad447a760 100644
--- a/fs/nfsd/nfs3xdr.c
+++ b/fs/nfsd/nfs3xdr.c
@@ -400,53 +400,41 @@ nfs3svc_decode_readargs(struct svc_rqst *rqstp, __be32 *p)
int
nfs3svc_decode_writeargs(struct svc_rqst *rqstp, __be32 *p)
{
+ struct xdr_stream *xdr = &rqstp->rq_xdr_stream;
struct nfsd3_writeargs *args = rqstp->rq_argp;
- unsigned int len, hdr, dlen;
u32 max_blocksize = svc_max_payload(rqstp);
struct kvec *head = rqstp->rq_arg.head;
struct kvec *tail = rqstp->rq_arg.tail;
+ size_t remaining;
- p = decode_fh(p, &args->fh);
+ if (!svcxdr_decode_nfs_fh3(xdr, &args->fh))
+ return XDR_DECODE_FAILED;
+ p = xdr_inline_decode(xdr, sizeof(__be32) * 5);
if (!p)
- return 0;
+ return XDR_DECODE_FAILED;
p = xdr_decode_hyper(p, &args->offset);
+ args->count = be32_to_cpup(p++);
+ args->stable = be32_to_cpup(p++);
- args->count = ntohl(*p++);
- args->stable = ntohl(*p++);
- len = args->len = ntohl(*p++);
- if ((void *)p > head->iov_base + head->iov_len)
- return 0;
- /*
- * The count must equal the amount of data passed.
- */
- if (args->count != args->len)
- return 0;
-
- /*
- * Check to make sure that we got the right number of
- * bytes.
- */
- hdr = (void*)p - head->iov_base;
- dlen = head->iov_len + rqstp->rq_arg.page_len + tail->iov_len - hdr;
- /*
- * Round the length of the data which was specified up to
- * the next multiple of XDR units and then compare that
- * against the length which was actually received.
- * Note that when RPCSEC/GSS (for example) is used, the
- * data buffer can be padded so dlen might be larger
- * than required. It must never be smaller.
- */
- if (dlen < XDR_QUADLEN(len)*4)
- return 0;
+ /* opaque data */
+ args->len = be32_to_cpup(p++);
+ /* request sanity */
+ if (args->count != args->len)
+ return XDR_DECODE_FAILED;
+ remaining = head->iov_len + rqstp->rq_arg.page_len + tail->iov_len;
+ remaining -= xdr_stream_pos(xdr);
+ if (remaining < xdr_align_size(args->len))
+ return XDR_DECODE_FAILED;
if (args->count > max_blocksize) {
args->count = max_blocksize;
- len = args->len = max_blocksize;
+ args->len = max_blocksize;
}
- args->first.iov_base = (void *)p;
- args->first.iov_len = head->iov_len - hdr;
- return 1;
+ args->first.iov_base = p;
+ args->first.iov_len = head->iov_len - xdr_stream_pos(xdr);
+
+ return XDR_DECODE_DONE;
}
int
