Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx>
---
fs/nfsd/nfsxdr.c | 56 ++++++++++++++++++++----------------------------------
1 file changed, 21 insertions(+), 35 deletions(-)
diff --git a/fs/nfsd/nfsxdr.c b/fs/nfsd/nfsxdr.c
index 7488fb396627..68a17a9b750f 100644
--- a/fs/nfsd/nfsxdr.c
+++ b/fs/nfsd/nfsxdr.c
@@ -264,47 +264,33 @@ nfssvc_decode_readargs(struct svc_rqst *rqstp, __be32 *p)
int
nfssvc_decode_writeargs(struct svc_rqst *rqstp, __be32 *p)
{
+ struct xdr_stream *xdr = &rqstp->rq_xdr_stream;
struct nfsd_writeargs *args = rqstp->rq_argp;
- unsigned int len, hdr, dlen;
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_fhandle(xdr, &args->fh))
+ return XDR_DECODE_FAILED;
+ p = xdr_inline_decode(xdr, sizeof(__be32) * 4);
if (!p)
- return 0;
-
- p++; /* beginoffset */
- args->offset = ntohl(*p++); /* offset */
- p++; /* totalcount */
- len = args->len = ntohl(*p++);
- /*
- * The protocol specifies a maximum of 8192 bytes.
- */
- if (len > NFSSVC_MAXBLKSIZE_V2)
- return 0;
-
- /*
- * Check to make sure that we got the right number of
- * bytes.
- */
- hdr = (void*)p - head->iov_base;
- if (hdr > head->iov_len)
- return 0;
- dlen = head->iov_len + rqstp->rq_arg.page_len - hdr;
+ return XDR_DECODE_FAILED;
+ p++; /* beginoffset is ignored */
+ args->offset = be32_to_cpup(p++);
+ p++; /* totalcount is ignored */
- /*
- * 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++);
+ if (args->len > NFSSVC_MAXBLKSIZE_V2)
+ 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;
+ args->first.iov_base = p;
+ args->first.iov_len = head->iov_len - xdr_stream_pos(xdr);
- args->first.iov_base = (void *)p;
- args->first.iov_len = head->iov_len - hdr;
- return 1;
+ return XDR_DECODE_DONE;
}
int
