NFSD: Update the SYMLINK3args decoder to use struct xdr_stream

Similar to the WRITE decoder, code that checks the sanity of the
payload size is re-wired to work with xdr_stream infrastructure.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
This commit is contained in:
Chuck Lever 2020-10-20 16:01:16 -04:00
parent 83374c278d
commit da39201637

View file

@ -616,25 +616,28 @@ nfs3svc_decode_mkdirargs(struct svc_rqst *rqstp, __be32 *p)
int
nfs3svc_decode_symlinkargs(struct svc_rqst *rqstp, __be32 *p)
{
struct xdr_stream *xdr = &rqstp->rq_arg_stream;
struct nfsd3_symlinkargs *args = rqstp->rq_argp;
char *base = (char *)p;
size_t dlen;
struct kvec *head = rqstp->rq_arg.head;
struct kvec *tail = rqstp->rq_arg.tail;
size_t remaining;
if (!(p = decode_fh(p, &args->ffh)) ||
!(p = decode_filename(p, &args->fname, &args->flen)))
if (!svcxdr_decode_diropargs3(xdr, &args->ffh, &args->fname, &args->flen))
return 0;
p = decode_sattr3(p, &args->attrs, nfsd_user_namespace(rqstp));
args->tlen = ntohl(*p++);
args->first.iov_base = p;
args->first.iov_len = rqstp->rq_arg.head[0].iov_len;
args->first.iov_len -= (char *)p - base;
dlen = args->first.iov_len + rqstp->rq_arg.page_len +
rqstp->rq_arg.tail[0].iov_len;
if (dlen < XDR_QUADLEN(args->tlen) << 2)
if (!svcxdr_decode_sattr3(rqstp, xdr, &args->attrs))
return 0;
if (xdr_stream_decode_u32(xdr, &args->tlen) < 0)
return 0;
/* request sanity */
remaining = head->iov_len + rqstp->rq_arg.page_len + tail->iov_len;
remaining -= xdr_stream_pos(xdr);
if (remaining < xdr_align_size(args->tlen))
return 0;
args->first.iov_base = xdr->p;
args->first.iov_len = head->iov_len - xdr_stream_pos(xdr);
return 1;
}