diff options
| author | Stephane Grosjean <s.grosjean@peak-system.com> | 2014-05-20 11:38:56 +0200 |
|---|---|---|
| committer | Ben Hutchings <ben@decadent.org.uk> | 2014-06-09 13:29:14 +0100 |
| commit | f15c1e78cd172ba3a1e5049efcc8fbcb54198234 (patch) | |
| tree | 73724b880765c84887484e440ab2246f9327bc25 | |
| parent | b0bcd33beba3ebaceda3524e9872f106fde868de (diff) | |
can: peak_pci: prevent use after free at netdev removal
commit 0b5a958cf4df3a5cd578b861471e62138f55c85e upstream.
As remarked by Christopher R. Baker in his post at
http://marc.info/?l=linux-can&m=139707295706465&w=2
there's a possibility for an use after free condition at device removal.
This simplified patch introduces an additional variable to prevent the issue.
Thanks for catching this.
Reported-by: Christopher R. Baker <cbaker@rec.ri.cmu.edu>
Signed-off-by: Stephane Grosjean <s.grosjean@peak-system.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
| -rw-r--r-- | drivers/net/can/sja1000/peak_pci.c | 14 |
1 files changed, 9 insertions, 5 deletions
diff --git a/drivers/net/can/sja1000/peak_pci.c b/drivers/net/can/sja1000/peak_pci.c index 214795945bc..5192f861525 100644 --- a/drivers/net/can/sja1000/peak_pci.c +++ b/drivers/net/can/sja1000/peak_pci.c @@ -98,7 +98,7 @@ static int __devinit peak_pci_probe(struct pci_dev *pdev, { struct sja1000_priv *priv; struct peak_pci_chan *chan; - struct net_device *dev; + struct net_device *dev, *prev_dev; void __iomem *cfg_base, *reg_base; u16 sub_sys_id, icr; int i, err, channels; @@ -213,11 +213,13 @@ failure_remove_channels: /* Disable interrupts */ writew(0x0, cfg_base + PITA_ICR + 2); - for (dev = pci_get_drvdata(pdev); dev; dev = chan->prev_dev) { - unregister_sja1000dev(dev); - free_sja1000dev(dev); + for (dev = pci_get_drvdata(pdev); dev; dev = prev_dev) { priv = netdev_priv(dev); chan = priv->priv; + prev_dev = chan->prev_dev; + + unregister_sja1000dev(dev); + free_sja1000dev(dev); } pci_iounmap(pdev, reg_base); @@ -247,10 +249,12 @@ static void __devexit peak_pci_remove(struct pci_dev *pdev) /* Loop over all registered devices */ while (1) { + struct net_device *prev_dev = chan->prev_dev; + dev_info(&pdev->dev, "removing device %s\n", dev->name); unregister_sja1000dev(dev); free_sja1000dev(dev); - dev = chan->prev_dev; + dev = prev_dev; if (!dev) break; priv = netdev_priv(dev); |