1 files changed, 16 insertions, 20 deletions

diff --git a/fs/nfsd/nfs3proc.c b/fs/nfsd/nfs3proc.c
index 4418517f6f12..936eebd4c56d 100644
--- a/fs/nfsd/nfs3proc.c
+++ b/fs/nfsd/nfs3proc.c
@@ -150,13 +150,17 @@ nfsd3_proc_read(struct svc_rqst *rqstp)
 	unsigned int len;
 	int v;
 
-	argp->count = min_t(u32, argp->count, max_blocksize);
-
 	dprintk("nfsd: READ(3) %s %lu bytes at %Lu\n",
 				SVCFH_fmt(&argp->fh),
 				(unsigned long) argp->count,
 				(unsigned long long) argp->offset);
 
+	argp->count = min_t(u32, argp->count, max_blocksize);
+	if (argp->offset > (u64)OFFSET_MAX)
+		argp->offset = (u64)OFFSET_MAX;
+	if (argp->offset + argp->count > (u64)OFFSET_MAX)
+		argp->count = (u64)OFFSET_MAX - argp->offset;
+
 	v = 0;
 	len = argp->count;
 	resp->pages = rqstp->rq_next_page;
@@ -199,18 +203,19 @@ nfsd3_proc_write(struct svc_rqst *rqstp)
 				(unsigned long long) argp->offset,
 				argp->stable? " stable" : "");
 
+	resp->status = nfserr_fbig;
+	if (argp->offset > (u64)OFFSET_MAX ||
+	    argp->offset + argp->len > (u64)OFFSET_MAX)
+		return rpc_success;
+
 	fh_copy(&resp->fh, &argp->fh);
 	resp->committed = argp->stable;
 	nvecs = svc_fill_write_vector(rqstp, &argp->payload);
-	if (!nvecs) {
-		resp->status = nfserr_io;
-		goto out;
-	}
+
 	resp->status = nfsd_write(rqstp, &resp->fh, argp->offset,
 				  rqstp->rq_vec, nvecs, &cnt,
 				  resp->committed, resp->verf);
 	resp->count = cnt;
-out:
 	return rpc_success;
 }
 
@@ -438,22 +443,19 @@ nfsd3_proc_link(struct svc_rqst *rqstp)
 
 static void nfsd3_init_dirlist_pages(struct svc_rqst *rqstp,
 				     struct nfsd3_readdirres *resp,
-				     int count)
+				     u32 count)
 {
 	struct xdr_buf *buf = &resp->dirlist;
 	struct xdr_stream *xdr = &resp->xdr;
 
-	count = min_t(u32, count, svc_max_payload(rqstp));
+	count = clamp(count, (u32)(XDR_UNIT * 2), svc_max_payload(rqstp));
 
 	memset(buf, 0, sizeof(*buf));
 
 	/* Reserve room for the NULL ptr & eof flag (-2 words) */
 	buf->buflen = count - XDR_UNIT * 2;
 	buf->pages = rqstp->rq_next_page;
-	while (count > 0) {
-		rqstp->rq_next_page++;
-		count -= PAGE_SIZE;
-	}
+	rqstp->rq_next_page += (buf->buflen + PAGE_SIZE - 1) >> PAGE_SHIFT;
 
 	/* This is xdr_init_encode(), but it assumes that
 	 * the head kvec has already been consumed. */
@@ -462,7 +464,7 @@ static void nfsd3_init_dirlist_pages(struct svc_rqst *rqstp,
 	xdr->page_ptr = buf->pages;
 	xdr->iov = NULL;
 	xdr->p = page_address(*buf->pages);
-	xdr->end = xdr->p + (PAGE_SIZE >> 2);
+	xdr->end = (void *)xdr->p + min_t(u32, buf->buflen, PAGE_SIZE);
 	xdr->rqst = NULL;
 }
 
@@ -658,15 +660,9 @@ nfsd3_proc_commit(struct svc_rqst *rqstp)
 				argp->count,
 				(unsigned long long) argp->offset);
 
-	if (argp->offset > NFS_OFFSET_MAX) {
-		resp->status = nfserr_inval;
-		goto out;
-	}
-
 	fh_copy(&resp->fh, &argp->fh);
 	resp->status = nfsd_commit(rqstp, &resp->fh, argp->offset,
 				   argp->count, resp->verf);
-out:
 	return rpc_success;
 }