linux-kernel - Re: [PATCH 2/4] random: vDSO: Don't use PAGE_SIZE and PAGE

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <Zs2NFjfBKKjfoI2d@zx2c4.com>
Date: Tue, 27 Aug 2024 10:23:50 +0200
From: "Jason A. Donenfeld" <Jason@...c4.com>
To: Christophe Leroy <christophe.leroy@...roup.eu>
Cc: Theodore Ts'o <tytso@....edu>, Arnd Bergmann <arnd@...db.de>,
	Andy Lutomirski <luto@...nel.org>,
	Thomas Gleixner <tglx@...utronix.de>,
	Vincenzo Frascino <vincenzo.frascino@....com>,
	Ingo Molnar <mingo@...hat.com>, Borislav Petkov <bp@...en8.de>,
	Dave Hansen <dave.hansen@...ux.intel.com>, x86@...nel.org,
	"H. Peter Anvin" <hpa@...or.com>, linux-kernel@...r.kernel.org,
	linuxppc-dev@...ts.ozlabs.org, linux-arch@...r.kernel.org
Subject: Re: [PATCH 2/4] random: vDSO: Don't use PAGE_SIZE and PAGE_MASK

On Tue, Aug 27, 2024 at 10:16:18AM +0200, Christophe Leroy wrote:
> tglx or yourself suggested to put in a one of the vdso headers instead 
> of directly in getrandom.c. This is too fragile because PAGE_SIZE might 
> be absent in that header but arrive in getrandom.c through another header.

Oh jeeze, yea.

FYI, _PAGE_SIZE is defined on s390, so that might not be such a good
idea (from the previous version).

> The best would be to have an asm-generic definition of
> PAGE_SIZE and PAGE_MASK that all architectures use, but that's another
> level of work.

Yea that seems far too large of an operation to do here.

> > I'm really not a fan of making the code less idiomatic...
> 
> Ok, I have another idea, let's give it a try.

What's the other idea?