---

yaml
---
r: 322619
b: refs/heads/master
c: 1f1ea6c
h: refs/heads/master
i:
  322617: c2704ad
  322615: 4780cdc
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 21f498c2f73bd6150d82931f09965826dca0b5f2
+refs/heads/master: 1f1ea6c2d9d8c0be9ec56454b05315273b5de8ce

trunk/fs/nfs/nfs4proc.c

@@ -3739,7 +3739,7 @@ static void nfs4_write_cached_acl(struct inode *inode, struct page **pages, size
 	struct nfs4_cached_acl *acl;
 	size_t buflen = sizeof(*acl) + acl_len;
 
-	if (pages && buflen <= PAGE_SIZE) {
+	if (buflen <= PAGE_SIZE) {
 		acl = kmalloc(buflen, GFP_KERNEL);
 		if (acl == NULL)
 			goto out;
@@ -3784,7 +3784,6 @@ static ssize_t __nfs4_get_acl_uncached(struct inode *inode, void *buf, size_t bu
 	};
 	unsigned int npages = DIV_ROUND_UP(buflen, PAGE_SIZE);
 	int ret = -ENOMEM, i;
-	size_t acl_len = 0;
 
 	/* As long as we're doing a round trip to the server anyway,
 	 * let's be prepared for a page of acl data. */
@@ -3807,32 +3806,26 @@ static ssize_t __nfs4_get_acl_uncached(struct inode *inode, void *buf, size_t bu
 	args.acl_len = npages * PAGE_SIZE;
 	args.acl_pgbase = 0;
 
-	/* Let decode_getfacl know not to fail if the ACL data is larger than
-	 * the page we send as a guess */
-	if (buf == NULL)
-		res.acl_flags |= NFS4_ACL_LEN_REQUEST;
-
 	dprintk("%s  buf %p buflen %zu npages %d args.acl_len %zu\n",
 		__func__, buf, buflen, npages, args.acl_len);
 	ret = nfs4_call_sync(NFS_SERVER(inode)->client, NFS_SERVER(inode),
 			     &msg, &args.seq_args, &res.seq_res, 0);
 	if (ret)
 		goto out_free;
 
-	acl_len = res.acl_len;
-	if (acl_len > args.acl_len)
-		nfs4_write_cached_acl(inode, NULL, 0, acl_len);
-	else
-		nfs4_write_cached_acl(inode, pages, res.acl_data_offset,
-				      acl_len);
-	if (buf) {
+	/* Handle the case where the passed-in buffer is too short */
+	if (res.acl_flags & NFS4_ACL_TRUNC) {
+		/* Did the user only issue a request for the acl length? */
+		if (buf == NULL)
+			goto out_ok;
 		ret = -ERANGE;
-		if (acl_len > buflen)
-			goto out_free;
-		_copy_from_pages(buf, pages, res.acl_data_offset,
-				acl_len);
+		goto out_free;
 	}
-	ret = acl_len;
+	nfs4_write_cached_acl(inode, pages, res.acl_data_offset, res.acl_len);
+	if (buf)
+		_copy_from_pages(buf, pages, res.acl_data_offset, res.acl_len);
+out_ok:
+	ret = res.acl_len;
 out_free:
 	for (i = 0; i < npages; i++)
 		if (pages[i])

trunk/fs/nfs/nfs4xdr.c

@@ -5072,18 +5072,14 @@ static int decode_getacl(struct xdr_stream *xdr, struct rpc_rqst *req,
 		 * are stored with the acl data to handle the problem of
 		 * variable length bitmaps.*/
 		res->acl_data_offset = xdr_stream_pos(xdr) - pg_offset;
-
-		/* We ignore &savep and don't do consistency checks on
-		 * the attr length.  Let userspace figure it out.... */
 		res->acl_len = attrlen;
-		if (attrlen > (xdr->nwords << 2)) {
-			if (res->acl_flags & NFS4_ACL_LEN_REQUEST) {
-				/* getxattr interface called with a NULL buf */
-				goto out;
-			}
+
+		/* Check for receive buffer overflow */
+		if (res->acl_len > (xdr->nwords << 2) ||
+		    res->acl_len + res->acl_data_offset > xdr->buf->page_len) {
+			res->acl_flags |= NFS4_ACL_TRUNC;
 			dprintk("NFS: acl reply: attrlen %u > page_len %u\n",
 					attrlen, xdr->nwords << 2);
-			return -EINVAL;
 		}
 	} else
 		status = -EOPNOTSUPP;

trunk/include/linux/nfs_xdr.h

@@ -652,7 +652,7 @@ struct nfs_getaclargs {
 };
 
 /* getxattr ACL interface flags */
-#define NFS4_ACL_LEN_REQUEST	0x0001	/* zero length getxattr buffer */
+#define NFS4_ACL_TRUNC		0x0001	/* ACL was truncated */
 struct nfs_getaclres {
 	size_t				acl_len;
 	size_t				acl_data_offset;