Patch "net: korina: Fix NAPI versus resources freeing" has been added to the 4.4-stable tree

Patch "net: korina: Fix NAPI versus resources freeing" has been added to the 4.4-stable tree

[gregkh]

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

    net: korina: Fix NAPI versus resources freeing

to the 4.4-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:
     net-korina-fix-napi-versus-resources-freeing.patch
and it can be found in the queue-4.4 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 e6afb1ad88feddf2347ea779cfaf4d03d3cd40b6 Mon Sep 17 00:00:00 2001
From: Florian Fainelli <f.fainelli@gmail.com>
Date: Fri, 23 Dec 2016 19:56:56 -0800
Subject: net: korina: Fix NAPI versus resources freeing

From: Florian Fainelli <f.fainelli@gmail.com>

commit e6afb1ad88feddf2347ea779cfaf4d03d3cd40b6 upstream.

Commit beb0babfb77e ("korina: disable napi on close and restart")
introduced calls to napi_disable() that were missing before,
unfortunately this leaves a small window during which NAPI has a chance
to run, yet we just freed resources since korina_free_ring() has been
called:

Fix this by disabling NAPI first then freeing resource, and make sure
that we also cancel the restart task before doing the resource freeing.

Fixes: beb0babfb77e ("korina: disable napi on close and restart")
Reported-by: Alexandros C. Couloumbis <alex@ozo.com>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/net/ethernet/korina.c |    8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

--- a/drivers/net/ethernet/korina.c
+++ b/drivers/net/ethernet/korina.c
@@ -900,10 +900,10 @@ static void korina_restart_task(struct w
 				DMA_STAT_DONE | DMA_STAT_HALT | DMA_STAT_ERR,
 				&lp->rx_dma_regs->dmasm);
 
-	korina_free_ring(dev);
-
 	napi_disable(&lp->napi);
 
+	korina_free_ring(dev);
+
 	if (korina_init(dev) < 0) {
 		printk(KERN_ERR "%s: cannot restart device\n", dev->name);
 		return;
@@ -1064,12 +1064,12 @@ static int korina_close(struct net_devic
 	tmp = tmp | DMA_STAT_DONE | DMA_STAT_HALT | DMA_STAT_ERR;
 	writel(tmp, &lp->rx_dma_regs->dmasm);
 
-	korina_free_ring(dev);
-
 	napi_disable(&lp->napi);
 
 	cancel_work_sync(&lp->restart_task);
 
+	korina_free_ring(dev);
+
 	free_irq(lp->rx_irq, dev);
 	free_irq(lp->tx_irq, dev);
 	free_irq(lp->ovr_irq, dev);


Patches currently in stable-queue which might be from f.fainelli@gmail.com are

queue-4.4/net-korina-fix-napi-versus-resources-freeing.patch
queue-4.4/arm-dts-bcm5301x-correct-gic_ppi-interrupt-flags.patch
queue-4.4/net-bgmac-start-transmit-queue-in-bgmac_open.patch
queue-4.4/net-bgmac-fix-sof-bit-checking.patch
queue-4.4/net-bgmac-remove-superflous-netif_carrier_on.patch