Re: [PATCH 0/2] introduce DUMP_PREFIX_UNHASHED for hex dumps

From: Sergey Senozhatsky
Date: Mon Jan 18 2021 - 19:54:19 EST


On (21/01/18 13:03), Timur Tabi wrote:
> On 1/18/21 12:26 PM, Matthew Wilcox wrote:
> > Don't make it easy. And don't make it look like they're doing
> > something innocent. DUMP_PREFIX_SECURITY_HOLE would be OK
> > by me. DUMP_PREFIX_LEAK_INFORMATION would work fine too.
> > DUMP_PREFIX_MAKE_ATTACKERS_LIFE_EASY might be a bit too far.
>
> It's already extremely easy to replace %p with %px in your own printks, so I
> don't really understand your argument.

I like the idea of a more radical name, e.g. DUMP_PREFIX_RAW_POINTERS or
something similar.

> Seriously, this patch should not be so contentious. If you want hashed
> addresses, then nothing changes. If you need unhashed addresses while
> debugging, then use DUMP_PREFIX_UNHASHED. Just like you can use %px in
> printk. I never use %p in my printks, but then I never submit code upstream
> that prints addresses, hashed or unhashed.

So maybe DUMP_PREFIX_UNHASHED can do the unhashed dump only when
CONFIG_DEBUG_KERNEL=y and fallback to DUMP_PREFIX_ADDRESS otherwise?

-ss