Patchwork [3.5.y.z,extended,stable] Patch "net: usb: Fix memory leak on Tx data path" has been added to staging queue

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Submitter Herton Ronaldo Krzesinski
Date Dec. 12, 2012, 5:11 a.m.
Message ID <1355289069-31010-1-git-send-email-herton.krzesinski@canonical.com>
Download mbox | patch
Permalink /patch/205409/
State New
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Comments

Herton Ronaldo Krzesinski - Dec. 12, 2012, 5:11 a.m.
This is a note to let you know that I have just added a patch titled

    net: usb: Fix memory leak on Tx data path

to the linux-3.5.y-queue branch of the 3.5.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.5.y-queue

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.5.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Herton

------

From 834ffb23f3593ed395b8b915ea0f5f7c56620373 Mon Sep 17 00:00:00 2001
From: Hemant Kumar <hemantk@codeaurora.org>
Date: Thu, 25 Oct 2012 18:17:54 +0000
Subject: [PATCH] net: usb: Fix memory leak on Tx data path

commit 39707c2a3ba5011038b363f84d37c8a98d2d9db1 upstream.

Driver anchors the tx urbs and defers the urb submission if
a transmit request comes when the interface is suspended.
Anchoring urb increments the urb reference count. These
deferred urbs are later accessed by calling usb_get_from_anchor()
for submission during interface resume. usb_get_from_anchor()
unanchors the urb but urb reference count remains same.
This causes the urb reference count to remain non-zero
after usb_free_urb() gets called and urb never gets freed.
Hence call usb_put_urb() after anchoring the urb to properly
balance the reference count for these deferred urbs. Also,
unanchor these deferred urbs during disconnect, to free them
up.

Signed-off-by: Hemant Kumar <hemantk@codeaurora.org>
Acked-by: Oliver Neukum <oneukum@suse.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com>
---
 drivers/net/usb/usbnet.c |    3 +++
 1 file changed, 3 insertions(+)

--
1.7.9.5

Patch

diff --git a/drivers/net/usb/usbnet.c b/drivers/net/usb/usbnet.c
index f2716a4..a936201 100644
--- a/drivers/net/usb/usbnet.c
+++ b/drivers/net/usb/usbnet.c
@@ -1161,6 +1161,7 @@  netdev_tx_t usbnet_start_xmit (struct sk_buff *skb,
 		usb_anchor_urb(urb, &dev->deferred);
 		/* no use to process more packets */
 		netif_stop_queue(net);
+		usb_put_urb(urb);
 		spin_unlock_irqrestore(&dev->txq.lock, flags);
 		netdev_dbg(dev->net, "Delaying transmission for resumption\n");
 		goto deferred;
@@ -1313,6 +1314,8 @@  void usbnet_disconnect (struct usb_interface *intf)

 	cancel_work_sync(&dev->kevent);

+	usb_scuttle_anchored_urbs(&dev->deferred);
+
 	if (dev->driver_info->unbind)
 		dev->driver_info->unbind (dev, intf);