Re: [PATCH] DAC960.c - Null ptr fixes

[Jim Treadway]

On Thu, 24 May 2001, Praveen Srinivasan wrote:

> Hi,
> Using the Stanford checker, we searched for null-pointer bugs in the linux
> kernel code. This patch fixes numerous unchecked pointers in the DAC960
> driver (DAC960.c).
>
> Praveen Srinivasan and Frederick Akalin
>
>
> --- ../linux/./drivers/block/DAC960.c	Tue Feb 20 21:26:22 2001
> +++ ./drivers/block/DAC960.c	Mon May  7 21:56:30 2001
> @@ -508,6 +508,9 @@
>    DAC960_Command_T *Command = DAC960_AllocateCommand(Controller);
>    DAC960_V1_CommandMailbox_T *CommandMailbox = &Command->V1.CommandMailbox;
>    DAC960_V1_CommandStatus_T CommandStatus;
> +  if(Command == NULL) {
> +    return 0;
> +  }
>    DAC960_V1_ClearCommand(Command);
>    Command->CommandType = DAC960_ImmediateCommand;
>    CommandMailbox->Type3.CommandOpcode = CommandOpcode;

[other similar examples snipped]

Shouldn't the check for NULL occur before '&Command->V1.CommandMailbox'?