[media] [Resend] viacam: Don't explode if pci_find_bus() returns NULL

In the unlikely case that pci_find_bus() should return NULL viacam_serial_is_enabled() is going to dereference a NULL pointer and blow up. Better safe than sorry, so be defensive and check the pointer. Signed-off-by: Jesper Juhl <[email protected]> Acked-by: Jonathan Corbet <[email protected]> Signed-off-by: Mauro Carvalho Chehab <[email protected]>
RyanHsu · Sep 11, 2011 · c8814df · c8814df
1 parent 6a02a33
commit c8814df
Showing 1 changed file with 2 additions and 0 deletions.
diff --git a/drivers/media/video/via-camera.c b/drivers/media/video/via-camera.c
@@ -1332,6 +1332,8 @@ static __devinit bool viacam_serial_is_enabled(void)
 	struct pci_bus *pbus = pci_find_bus(0, 0);
 	u8 cbyte;
 
+	if (!pbus)
+		return false;
 	pci_bus_read_config_byte(pbus, VIACAM_SERIAL_DEVFN,
 			VIACAM_SERIAL_CREG, &cbyte);
 	if ((cbyte & VIACAM_SERIAL_BIT) == 0)