ssb: fix NULL ptr deref when pcihost_wrapper is used

commit da1fdb02d9200ff28b6f3a380d21930335fe5429 upstream.

Ethernet driver b44 does register ssb by it's pcihost_wrapper
and doesn't set ssb_chipcommon. A check on this value
introduced with commit d53cdbb94a52a920d5420ed64d986c3523a56743
and ea2db495f92ad2cf3301623e60cb95b4062bc484 triggers:

BUG: unable to handle kernel NULL pointer dereference at 00000010
IP: [<c1266c36>] ssb_is_sprom_available+0x16/0x30

Signed-off-by: Christoph Fritz <chf.fritz@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Cc: Larry Finger <Larry.Finger@lwfinger.net>
Cc: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/ssb/pci.c b/drivers/ssb/pci.c
index 5bb1278759c1dbcb7f88144d6dba51eaab39759d..243db85dbdb8181382f1c8f9035b7f601ae1c1a8 100644 (file)
--- a/drivers/ssb/pci.c
+++ b/drivers/ssb/pci.c
@@ -624,9 +624,12 @@ static int ssb_pci_sprom_get(struct ssb_bus *bus,
                ssb_printk(KERN_ERR PFX "No SPROM available!\n");
                return -ENODEV;
        }
-
-       bus->sprom_offset = (bus->chipco.dev->id.revision < 31) ?
-               SSB_SPROM_BASE1 : SSB_SPROM_BASE31;
+       if (bus->chipco.dev) {  /* can be unavailible! */
+               bus->sprom_offset = (bus->chipco.dev->id.revision < 31) ?
+                       SSB_SPROM_BASE1 : SSB_SPROM_BASE31;
+       } else {
+               bus->sprom_offset = SSB_SPROM_BASE1;
+       }
 
        buf = kcalloc(SSB_SPROMSIZE_WORDS_R123, sizeof(u16), GFP_KERNEL);
        if (!buf)

diff --git a/drivers/ssb/sprom.c b/drivers/ssb/sprom.c
index 042c643957d7d02958a5885d5038f9ce4274eb9c..5f7154d9d04e09fc0ef2c892bfac73cac03b0f53 100644 (file)
--- a/drivers/ssb/sprom.c
+++ b/drivers/ssb/sprom.c
@@ -188,6 +188,7 @@ bool ssb_is_sprom_available(struct ssb_bus *bus)
        /* this routine differs from specs as we do not access SPROM directly
           on PCMCIA */
        if (bus->bustype == SSB_BUSTYPE_PCI &&
+           bus->chipco.dev &&  /* can be unavailible! */
            bus->chipco.dev->id.revision >= 31)
                return bus->chipco.capabilities & SSB_CHIPCO_CAP_SPROM;