linux-kernel - Re: [PATCH v6 3/7] treewide: use get_random

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Message-ID: <Y0TcOH/BDfg5c1gj@zx2c4.com>
Date:   Mon, 10 Oct 2022 21:00:08 -0600
From:   "Jason A. Donenfeld" <Jason@...c4.com>
To:     "Elliott, Robert (Servers)" <elliott@....com>
Cc:     "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        "patches@...ts.linux.dev" <patches@...ts.linux.dev>,
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        Toke Høiland-Jørgensen <toke@...e.dk>
Subject: Re: [PATCH v6 3/7] treewide: use get_random_{u8,u16}() when
 possible, part 1

On Tue, Oct 11, 2022 at 01:18:40AM +0000, Elliott, Robert (Servers) wrote:
> 
> > diff --git a/crypto/testmgr.c b/crypto/testmgr.c
> ...
> > @@ -944,7 +944,7 @@ static void generate_random_bytes(u8 *buf, size_t count)
> >  	default:
> >  		/* Fully random bytes */
> >  		for (i = 0; i < count; i++)
> > -			buf[i] = (u8)prandom_u32();
> > +			buf[i] = get_random_u8();
> 
> Should that whole for loop be replaced with this?
>     get_random_bytes(buf, count);

Wow, that's kind of grotesque. Yea, it certainly should. But that's
beyond the scope of this patchset. I'll send a follow-up patch just for
this case to Herbert after this cleanup lands, though.

Jason