From a51b5b737a0be93fae6ea2a18df03ab2359a3f4b Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Wed, 21 Oct 2020 12:18:36 -0400 Subject: NFSD: Update the NFSv2 WRITE argument decoder to use struct xdr_stream Signed-off-by: Chuck Lever --- fs/nfsd/nfsxdr.c | 52 +++++++++++++++++++++------------------------------- 1 file changed, 21 insertions(+), 31 deletions(-) (limited to 'fs/nfsd/nfsxdr.c') diff --git a/fs/nfsd/nfsxdr.c b/fs/nfsd/nfsxdr.c index 1eacaa2c13a9..11d27b219cff 100644 --- a/fs/nfsd/nfsxdr.c +++ b/fs/nfsd/nfsxdr.c @@ -266,46 +266,36 @@ 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_arg_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; + u32 beginoffset, totalcount; + size_t remaining; - p = decode_fh(p, &args->fh); - if (!p) + if (!svcxdr_decode_fhandle(xdr, &args->fh)) 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) + /* beginoffset is ignored */ + if (xdr_stream_decode_u32(xdr, &beginoffset) < 0) 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) + if (xdr_stream_decode_u32(xdr, &args->offset) < 0) + return 0; + /* totalcount is ignored */ + if (xdr_stream_decode_u32(xdr, &totalcount) < 0) return 0; - dlen = head->iov_len + rqstp->rq_arg.page_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) + /* opaque data */ + if (xdr_stream_decode_u32(xdr, &args->len) < 0) + return 0; + if (args->len > NFSSVC_MAXBLKSIZE_V2) + return 0; + 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 0; + args->first.iov_base = xdr->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; } -- cgit v1.2.3-58-ga151