diff options
| author | Stephane Grosjean <s.grosjean@peak-system.com> | 2014-05-20 11:38:56 +0200 |
|---|---|---|
| committer | Marc Kleine-Budde <mkl@pengutronix.de> | 2014-05-21 08:17:03 +0200 |
| commit | 0b5a958cf4df3a5cd578b861471e62138f55c85e (patch) | |
| tree | be02fbf4f83f6a1a9c89239951c6da0ba6720355 | |
| parent | 78ff4be45a4c51d8fb21ad92e4fabb467c6c3eeb (diff) | |
can: peak_pci: prevent use after free at netdev removal
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.
Cc: linux-stable <stable@vger.kernel.org>
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>
| -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 c540e3d12e3..564933ae218 100644 --- a/drivers/net/can/sja1000/peak_pci.c +++ b/drivers/net/can/sja1000/peak_pci.c @@ -551,7 +551,7 @@ static int peak_pci_probe(struct pci_dev *pdev, const struct pci_device_id *ent) { 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; @@ -688,11 +688,13 @@ failure_remove_channels: writew(0x0, cfg_base + PITA_ICR + 2); chan = NULL; - 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); } /* free any PCIeC resources too */ @@ -726,10 +728,12 @@ static void 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) { /* do that only for first channel */ |