NFSD: Use xdr_inline_decode() to decode NFSv3 symlinks

[ Upstream commit c3d2a04f05c590303c125a176e6e43df4a436fdb ]

Replace the check for buffer over/underflow with a helper that is
commonly used for this purpose. The helper also sets xdr->nwords
correctly after successfully linearizing the symlink argument into
the stream's scratch buffer.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Chuck Lever 2022-09-12 17:23:02 -04:00 committed by Ksawlii
parent f6d3097d21
commit 8e65b00166

View file

@ -616,8 +616,6 @@ nfs3svc_decode_symlinkargs(struct svc_rqst *rqstp, struct xdr_stream *xdr)
{
struct nfsd3_symlinkargs *args = rqstp->rq_argp;
struct kvec *head = rqstp->rq_arg.head;
struct kvec *tail = rqstp->rq_arg.tail;
size_t remaining;
if (!svcxdr_decode_diropargs3(xdr, &args->ffh, &args->fname, &args->flen))
return false;
@ -626,16 +624,10 @@ nfs3svc_decode_symlinkargs(struct svc_rqst *rqstp, struct xdr_stream *xdr)
if (xdr_stream_decode_u32(xdr, &args->tlen) < 0)
return false;
/* 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 false;
args->first.iov_base = xdr->p;
/* symlink_data */
args->first.iov_len = head->iov_len - xdr_stream_pos(xdr);
return true;
args->first.iov_base = xdr_inline_decode(xdr, args->tlen);
return args->first.iov_base != NULL;
}
bool