Patch "USB: fix linked-list corruption in rh_call_control()" has been added to the 4.9-stable tree

[<gregkh@linuxfoundation.org>]

This is a note to let you know that I've just added the patch titled

    USB: fix linked-list corruption in rh_call_control()

to the 4.9-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     usb-fix-linked-list-corruption-in-rh_call_control.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 1633682053a7ee8058e10c76722b9b28e97fb73f Mon Sep 17 00:00:00 2001
From: Alan Stern <stern@rowland.harvard.edu>
Date: Fri, 24 Mar 2017 13:38:28 -0400
Subject: USB: fix linked-list corruption in rh_call_control()

From: Alan Stern <stern@rowland.harvard.edu>

commit 1633682053a7ee8058e10c76722b9b28e97fb73f upstream.

Using KASAN, Dmitry found a bug in the rh_call_control() routine: If
buffer allocation fails, the routine returns immediately without
unlinking its URB from the control endpoint, eventually leading to
linked-list corruption.

This patch fixes the problem by jumping to the end of the routine
(where the URB is unlinked) when an allocation failure occurs.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-and-tested-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/usb/core/hcd.c |    7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

--- a/drivers/usb/core/hcd.c
+++ b/drivers/usb/core/hcd.c
@@ -520,8 +520,10 @@ static int rh_call_control (struct usb_h
 	 */
 	tbuf_size =  max_t(u16, sizeof(struct usb_hub_descriptor), wLength);
 	tbuf = kzalloc(tbuf_size, GFP_KERNEL);
-	if (!tbuf)
-		return -ENOMEM;
+	if (!tbuf) {
+		status = -ENOMEM;
+		goto err_alloc;
+	}
 
 	bufp = tbuf;
 
@@ -734,6 +736,7 @@ error:
 	}
 
 	kfree(tbuf);
+ err_alloc:
 
 	/* any errors get returned through the urb completion */
 	spin_lock_irq(&hcd_root_hub_lock);


Patches currently in stable-queue which might be from stern@rowland.harvard.edu are

queue-4.9/usb-fix-linked-list-corruption-in-rh_call_control.patch