[PATCH 4.7 22/69] configfs: Return -EFBIG from configfs_write_bin_file.

[Greg Kroah-Hartman]

4.7-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Phil Turnbull <phil.turnbull@xxxxxxxxxx>

commit 42857cf512cb34c2c8cb50f1e766689d979d64e0 upstream.

The check for writing more than cb_max_size bytes does not 'goto out' so
it is a no-op which allows users to vmalloc an arbitrary amount.

Fixes: 03607ace807b ("configfs: implement binary attributes")
Signed-off-by: Phil Turnbull <phil.turnbull@xxxxxxxxxx>
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 fs/configfs/file.c |    1 +
 1 file changed, 1 insertion(+)

--- a/fs/configfs/file.c
+++ b/fs/configfs/file.c
@@ -333,6 +333,7 @@ configfs_write_bin_file(struct file *fil
 		if (bin_attr->cb_max_size &&
 			*ppos + count > bin_attr->cb_max_size) {
 			len = -EFBIG;
+			goto out;
 		}
 
 		tbuf = vmalloc(*ppos + count);