From 6232dbbcffc617a5a47596b2ec347b24dc2dd2fd Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Fri, 26 Oct 2007 13:31:52 -0400 Subject: [PATCH] NFS: Use unsigned intermediates for manipulating header lengths (NFSv2 XDR) Clean up: prevent length underflow and mixed sign comparisons when unmarshalling NFS version 2 read, readdir, and readlink replies. Signed-off-by: Chuck Lever Signed-off-by: Trond Myklebust --- fs/nfs/nfs2xdr.c | 24 ++++++++++++++---------- 1 file changed, 14 insertions(+), 10 deletions(-) diff --git a/fs/nfs/nfs2xdr.c b/fs/nfs/nfs2xdr.c index 668ab96c7b59..1f7ea675e0c5 100644 --- a/fs/nfs/nfs2xdr.c +++ b/fs/nfs/nfs2xdr.c @@ -262,7 +262,9 @@ static int nfs_xdr_readres(struct rpc_rqst *req, __be32 *p, struct nfs_readres *res) { struct kvec *iov = req->rq_rcv_buf.head; - int status, count, recvd, hdrlen; + size_t hdrlen; + u32 count, recvd; + int status; if ((status = ntohl(*p++))) return -nfs_stat_to_errno(status); @@ -273,7 +275,7 @@ nfs_xdr_readres(struct rpc_rqst *req, __be32 *p, struct nfs_readres *res) hdrlen = (u8 *) p - (u8 *) iov->iov_base; if (iov->iov_len < hdrlen) { dprintk("NFS: READ reply header overflowed:" - "length %d > %Zu\n", hdrlen, iov->iov_len); + "length %Zu > %Zu\n", hdrlen, iov->iov_len); return -errno_NFSERR_IO; } else if (iov->iov_len != hdrlen) { dprintk("NFS: READ header is short. iovec will be shifted.\n"); @@ -283,11 +285,11 @@ nfs_xdr_readres(struct rpc_rqst *req, __be32 *p, struct nfs_readres *res) recvd = req->rq_rcv_buf.len - hdrlen; if (count > recvd) { dprintk("NFS: server cheating in read reply: " - "count %d > recvd %d\n", count, recvd); + "count %u > recvd %u\n", count, recvd); count = recvd; } - dprintk("RPC: readres OK count %d\n", count); + dprintk("RPC: readres OK count %u\n", count); if (count < res->count) res->count = count; @@ -423,9 +425,10 @@ nfs_xdr_readdirres(struct rpc_rqst *req, __be32 *p, void *dummy) struct xdr_buf *rcvbuf = &req->rq_rcv_buf; struct kvec *iov = rcvbuf->head; struct page **page; - int hdrlen, recvd; + size_t hdrlen; + unsigned int pglen, recvd; + u32 len; int status, nr; - unsigned int len, pglen; __be32 *end, *entry, *kaddr; if ((status = ntohl(*p++))) @@ -434,7 +437,7 @@ nfs_xdr_readdirres(struct rpc_rqst *req, __be32 *p, void *dummy) hdrlen = (u8 *) p - (u8 *) iov->iov_base; if (iov->iov_len < hdrlen) { dprintk("NFS: READDIR reply header overflowed:" - "length %d > %Zu\n", hdrlen, iov->iov_len); + "length %Zu > %Zu\n", hdrlen, iov->iov_len); return -errno_NFSERR_IO; } else if (iov->iov_len != hdrlen) { dprintk("NFS: READDIR header is short. iovec will be shifted.\n"); @@ -576,7 +579,8 @@ nfs_xdr_readlinkres(struct rpc_rqst *req, __be32 *p, void *dummy) { struct xdr_buf *rcvbuf = &req->rq_rcv_buf; struct kvec *iov = rcvbuf->head; - int hdrlen, len, recvd; + size_t hdrlen; + u32 len, recvd; char *kaddr; int status; @@ -584,14 +588,14 @@ nfs_xdr_readlinkres(struct rpc_rqst *req, __be32 *p, void *dummy) return -nfs_stat_to_errno(status); /* Convert length of symlink */ len = ntohl(*p++); - if (len >= rcvbuf->page_len || len <= 0) { + if (len >= rcvbuf->page_len) { dprintk("nfs: server returned giant symlink!\n"); return -ENAMETOOLONG; } hdrlen = (u8 *) p - (u8 *) iov->iov_base; if (iov->iov_len < hdrlen) { dprintk("NFS: READLINK reply header overflowed:" - "length %d > %Zu\n", hdrlen, iov->iov_len); + "length %Zu > %Zu\n", hdrlen, iov->iov_len); return -errno_NFSERR_IO; } else if (iov->iov_len != hdrlen) { dprintk("NFS: READLINK header is short. iovec will be shifted.\n"); -- 2.30.2