The patch titled
     usb-gadget-ether: Prevent oops caused by error interrupt race
has been removed from the -mm tree.  Its filename was
     usb-gadget-ether-prevent-oops-caused-by-error-interrupt.patch

This patch was dropped because an updated version will be merged

------------------------------------------------------
Subject: usb-gadget-ether: Prevent oops caused by error interrupt race
From: Benedikt Spranger <[EMAIL PROTECTED]>

An USB error interrupt (e.g.  disconnect) nukes the pending requests for an
ethernet gadget device asynchronously.  This can race against
eth_start_xmit(), where we end up dereferencing the list head itself.

The nuke code is serialized against eth_start_xmit via dev->req_lock, but
we need to check the list for empty first instead of unconditionally
accessing dev->tx_reqs.next.

This is a long standing bug, which should be fixed in stable as well.

Signed-off-by: Benedikt Spranger <[EMAIL PROTECTED]>
Signed-off-by: Thomas Gleixner <[EMAIL PROTECTED]>
Cc: David Brownell <[EMAIL PROTECTED]>
Cc: Greg KH <[EMAIL PROTECTED]>
Cc: <[EMAIL PROTECTED]>
Signed-off-by: Andrew Morton <[EMAIL PROTECTED]>
---

 drivers/usb/gadget/ether.c |   12 ++++++++++++
 1 file changed, 12 insertions(+)

diff -puN 
drivers/usb/gadget/ether.c~usb-gadget-ether-prevent-oops-caused-by-error-interrupt
 drivers/usb/gadget/ether.c
--- 
a/drivers/usb/gadget/ether.c~usb-gadget-ether-prevent-oops-caused-by-error-interrupt
+++ a/drivers/usb/gadget/ether.c
@@ -1957,8 +1957,20 @@ static int eth_start_xmit (struct sk_buf
        }
 
        spin_lock_irqsave(&dev->req_lock, flags);
+       /*
+        * dev->tx_reqs may be empty due to an error interrupt which
+        * nuked all requests.
+        */
+       if (list_empty(&dev->tx_reqs)) {
+               netif_stop_queue(net);
+               spin_unlock_irqrestore(&dev->req_lock, flags);
+               return 1;
+       }
+
        req = container_of (dev->tx_reqs.next, struct usb_request, list);
        list_del (&req->list);
+
+       /* last request in list: stop queue */
        if (list_empty (&dev->tx_reqs))
                netif_stop_queue (net);
        spin_unlock_irqrestore(&dev->req_lock, flags);
_

Patches currently in -mm which might be from [EMAIL PROTECTED] are

usb-gadget-ether-prevent-oops-caused-by-error-interrupt.patch
usb-gadget-ether-prevent-oops-caused-by-error-interrupt-race-v2-comments-update.patch

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