Re: [PATCH v2] vsprintf: Make sure argument to %pX specifier is valid

[Boris Ostrovsky <boris.ostrovsky@oracle.com>]

On 02/12/2015 11:33 AM, Boris Ostrovsky wrote:
>
>
> Also, for %*ph format, if we just go with falling through to plain 
> format and not marking somehow that we are printing a bad pointer:
>
>     unsigned badval = 0xab;
>     unsigned *badptr = &badval;
>     printk("badptr = %*ph\n", 1, badptr);
>
> console:
>     badptr = ab
>
> We don't know here whether badptr was pointing to 0xab or it itself 
> was 0xab.
>

Ugh, bad example. Here is what I meant:

     unsigned badval = 0xab;
     unsigned *badptr = &badval;
     unsigned *badvalptr = (void *)0xab;
     printk("badvalptr = %*ph badptr = %*ph\n", 1, badvalptr, 1, badptr);

console:
     badvalptr = ab badptr = ab


Sorry.

-boris