[PATCH] isdn: hfcpci: fix potential NULL pointer dereference

[Kangjie Lu]

In case ioremap fails, the fix reports an error and returns.

Signed-off-by: Kangjie Lu <k...@umn.edu>
---
 drivers/isdn/hardware/mISDN/hfcpci.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/isdn/hardware/mISDN/hfcpci.c 
b/drivers/isdn/hardware/mISDN/hfcpci.c
index ebb3fa2e1d00..b400d6528a56 100644
--- a/drivers/isdn/hardware/mISDN/hfcpci.c
+++ b/drivers/isdn/hardware/mISDN/hfcpci.c
@@ -2036,6 +2036,11 @@ setup_hw(struct hfc_pci *hc)
               "HFC-PCI: defined at mem %#lx fifo %#lx(%#lx) IRQ %d HZ %d\n",
               (u_long) hc->hw.pci_io, (u_long) hc->hw.fifos,
               (u_long) hc->hw.dmahandle, hc->irq, HZ);
+       if (unlikely(!hc->hw.pci_io)) {
+               printk(KERN_WARNING
+                      "HFC-PCI: ioremap failed!\n");
+               return 1;
+       }
        /* enable memory mapped ports, disable busmaster */
        pci_write_config_word(hc->pdev, PCI_COMMAND, PCI_ENA_MEMIO);
        hc->hw.int_m2 = 0;
-- 
2.17.1