[POWERPC] of_serial: Fix possible null dereference.
The of_serial driver queries the current-speed property and attempts
to use it to register the custom_divisor property of the uart_port.
However, if current-speed is not set, then this code will dereference
a bad pointer. The fix is to only set custom_divisor when a
current-speed property appears in the device tree.
Signed-off-by: Stephen Neuendorffer <stephen.neuendorffer@xilinx.com>
Signed-off-by: John Linn <john.linn@xilinx.com>
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
diff --git a/drivers/serial/of_serial.c b/drivers/serial/of_serial.c
index c0e50a4..8aacfb7 100644
--- a/drivers/serial/of_serial.c
+++ b/drivers/serial/of_serial.c
@@ -56,7 +56,9 @@
port->flags = UPF_SHARE_IRQ | UPF_BOOT_AUTOCONF | UPF_IOREMAP
| UPF_FIXED_PORT;
port->dev = &ofdev->dev;
- port->custom_divisor = *clk / (16 * (*spd));
+ /* If current-speed was set, then try not to change it. */
+ if (spd)
+ port->custom_divisor = *clk / (16 * (*spd));
return 0;
}