From: Greg Kroah-Hartman <gre...@linuxfoundation.org>
3.12-stable review patch. If anyone has any objections, please let me know.
===============
commit 0994b0a257557e18ee8f0b7c5f0f73fe2b54eec1 upstream.
Andrey Konovalov reported that we were not properly checking the upper
limit before of a device configuration size before calling
memdup_user(), which could cause some problems.
So set the upper limit to PAGE_SIZE * 4, which should be good enough for
all devices.
Reported-by: Andrey Konovalov <andreyk...@google.com>
Signed-off-by: Felipe Balbi <felipe.ba...@linux.intel.com>
Signed-off-by: Jiri Slaby <jsl...@suse.cz>
---
drivers/usb/gadget/inode.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/usb/gadget/inode.c b/drivers/usb/gadget/inode.c
index 4ac9e9928d67..2b56e59a413f 100644
--- a/drivers/usb/gadget/inode.c
+++ b/drivers/usb/gadget/inode.c
@@ -1849,7 +1849,8 @@ dev_config (struct file *fd, const char __user *buf,
size_t len, loff_t *ptr)
u32 tag;
char *kbuf;
- if (len < (USB_DT_CONFIG_SIZE + USB_DT_DEVICE_SIZE + 4))
+ if ((len < (USB_DT_CONFIG_SIZE + USB_DT_DEVICE_SIZE + 4)) ||
+ (len > PAGE_SIZE * 4))
return -EINVAL;
/* we might need to change message format someday */
--
2.11.0
