5.10-stable review patch. If anyone has any objections, please let me know.
------------------
From: Chuck Lever chuck.lever@oracle.com
[ Upstream commit c43b2f229a01969a7ccf94b033c5085e0ec2040c ]
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@oracle.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/nfsd/nfs3xdr.c | 51 +++++++++++++++++++---------------------------- 1 file changed, 20 insertions(+), 31 deletions(-)
diff --git a/fs/nfsd/nfs3xdr.c b/fs/nfsd/nfs3xdr.c index 2f32df15a7e87..c06467e8ac829 100644 --- a/fs/nfsd/nfs3xdr.c +++ b/fs/nfsd/nfs3xdr.c @@ -405,52 +405,41 @@ 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_arg_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 (!p) + if (!svcxdr_decode_nfs_fh3(xdr, &args->fh)) return 0; - p = xdr_decode_hyper(p, &args->offset); - - args->count = ntohl(*p++); - args->stable = ntohl(*p++); - len = args->len = ntohl(*p++); - if ((void *)p > head->iov_base + head->iov_len) + if (xdr_stream_decode_u64(xdr, &args->offset) < 0) return 0; - /* - * The count must equal the amount of data passed. - */ - if (args->count != args->len) + if (xdr_stream_decode_u32(xdr, &args->count) < 0) + return 0; + if (xdr_stream_decode_u32(xdr, &args->stable) < 0) 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) + /* opaque data */ + if (xdr_stream_decode_u32(xdr, &args->len) < 0) return 0;
+ /* request sanity */ + if (args->count != args->len) + 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; 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; + args->first.iov_base = xdr->p; + args->first.iov_len = head->iov_len - xdr_stream_pos(xdr); + return 1; }