[PATCH] configfs: Return -EFBIG from configfs_write_bin_file.

From: Phil Turnbull
Date: Thu Sep 15 2016 - 12:23:01 EST


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

diff --git a/fs/configfs/file.c b/fs/configfs/file.c
index c30cf49b69d2..2c6312db8516 100644
--- a/fs/configfs/file.c
+++ b/fs/configfs/file.c
@@ -333,6 +333,7 @@ configfs_write_bin_file(struct file *file, const char __user *buf,
if (bin_attr->cb_max_size &&
*ppos + count > bin_attr->cb_max_size) {
len = -EFBIG;
+ goto out;
}

tbuf = vmalloc(*ppos + count);
--
2.9.0.rc2