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* [PATCH 1/3] [POWERPC] of_serial: Fix possible null dereference.
@ 2008-03-20 14:43 John Linn
  2008-03-20 23:58 ` Grant Likely
  0 siblings, 1 reply; 3+ messages in thread
From: John Linn @ 2008-03-20 14:43 UTC (permalink / raw)
  To: linuxppc-dev; +Cc: John Linn

From: Stephen Neuendorffer <stephen.neuendorffer@xilinx.com>

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>
---
 drivers/serial/of_serial.c |    4 +++-
 1 files changed, 3 insertions(+), 1 deletions(-)

diff --git a/drivers/serial/of_serial.c b/drivers/serial/of_serial.c
index a64d858..2efb892 100644
--- a/drivers/serial/of_serial.c
+++ b/drivers/serial/of_serial.c
@@ -56,7 +56,9 @@ static int __devinit of_platform_serial_setup(struct of_device *ofdev,
 	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;
 }
-- 
1.5.2.1

^ permalink raw reply related	[flat|nested] 3+ messages in thread

* Re: [PATCH 1/3] [POWERPC] of_serial: Fix possible null dereference.
  2008-03-20 14:43 [PATCH 1/3] [POWERPC] of_serial: Fix possible null dereference John Linn
@ 2008-03-20 23:58 ` Grant Likely
  2008-03-21  1:41   ` Josh Boyer
  0 siblings, 1 reply; 3+ messages in thread
From: Grant Likely @ 2008-03-20 23:58 UTC (permalink / raw)
  To: John Linn, Josh Boyer, Arnd Bergmann; +Cc: linuxppc-dev

On Thu, Mar 20, 2008 at 8:43 AM, John Linn <john.linn@xilinx.com> wrote:
> From: Stephen Neuendorffer <stephen.neuendorffer@xilinx.com>
>
>  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>

This looks correct and appropriate to me.

Acked-by: Grant Likely <grant.likely@secretlab.ca>

Josh/Arnd, could either of you pick this up?

Cheers,
g.

>  ---
>   drivers/serial/of_serial.c |    4 +++-
>   1 files changed, 3 insertions(+), 1 deletions(-)
>
>  diff --git a/drivers/serial/of_serial.c b/drivers/serial/of_serial.c
>  index a64d858..2efb892 100644
>  --- a/drivers/serial/of_serial.c
>  +++ b/drivers/serial/of_serial.c
>  @@ -56,7 +56,9 @@ static int __devinit of_platform_serial_setup(struct of_device *ofdev,
>         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;
>   }
>  --
>  1.5.2.1
>
>
>
>  _______________________________________________
>  Linuxppc-dev mailing list
>  Linuxppc-dev@ozlabs.org
>  https://ozlabs.org/mailman/listinfo/linuxppc-dev
>



-- 
Grant Likely, B.Sc., P.Eng.
Secret Lab Technologies Ltd.

^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: [PATCH 1/3] [POWERPC] of_serial: Fix possible null dereference.
  2008-03-20 23:58 ` Grant Likely
@ 2008-03-21  1:41   ` Josh Boyer
  0 siblings, 0 replies; 3+ messages in thread
From: Josh Boyer @ 2008-03-21  1:41 UTC (permalink / raw)
  To: Grant Likely; +Cc: linuxppc-dev, John Linn, Arnd Bergmann

On Thu, 20 Mar 2008 17:58:07 -0600
"Grant Likely" <grant.likely@secretlab.ca> wrote:

> On Thu, Mar 20, 2008 at 8:43 AM, John Linn <john.linn@xilinx.com> wrote:
> > From: Stephen Neuendorffer <stephen.neuendorffer@xilinx.com>
> >
> >  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>
> 
> This looks correct and appropriate to me.
> 
> Acked-by: Grant Likely <grant.likely@secretlab.ca>

Agreed.

Acked-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>

> Josh/Arnd, could either of you pick this up?

Arnd, can you send this on to Andrew?  Or if you are busy I can.

josh

> >  ---
> >   drivers/serial/of_serial.c |    4 +++-
> >   1 files changed, 3 insertions(+), 1 deletions(-)
> >
> >  diff --git a/drivers/serial/of_serial.c b/drivers/serial/of_serial.c
> >  index a64d858..2efb892 100644
> >  --- a/drivers/serial/of_serial.c
> >  +++ b/drivers/serial/of_serial.c
> >  @@ -56,7 +56,9 @@ static int __devinit of_platform_serial_setup(struct of_device *ofdev,
> >         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;
> >   }
> >  --
> >  1.5.2.1
> >
> >
> >
> >  _______________________________________________
> >  Linuxppc-dev mailing list
> >  Linuxppc-dev@ozlabs.org
> >  https://ozlabs.org/mailman/listinfo/linuxppc-dev
> >
> 
> 
> 

^ permalink raw reply	[flat|nested] 3+ messages in thread

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2008-03-20 14:43 [PATCH 1/3] [POWERPC] of_serial: Fix possible null dereference John Linn
2008-03-20 23:58 ` Grant Likely
2008-03-21  1:41   ` Josh Boyer

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