[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <CALCETrX2Vi8vKk3Cee7EfiGxFUjS+Htn1gzyr_PQ+e9ktnAmTg@mail.gmail.com>
Date: Wed, 10 May 2017 17:18:33 -0700
From: Andy Lutomirski <luto@...nel.org>
To: Christoph Hellwig <hch@...radead.org>
Cc: Al Viro <viro@...iv.linux.org.uk>, Arnd Bergmann <arnd@...db.de>,
Andy Lutomirski <luto@...nel.org>, Ingo Molnar <mingo@...nel.org>, Greg KH <greg@...ah.com>,
Thomas Garnier <thgarnie@...gle.com>, Martin Schwidefsky <schwidefsky@...ibm.com>,
Heiko Carstens <heiko.carstens@...ibm.com>, Dave Hansen <dave.hansen@...el.com>,
Thomas Gleixner <tglx@...utronix.de>, David Howells <dhowells@...hat.com>,
René Nyffenegger <mail@...enyffenegger.ch>,
Andrew Morton <akpm@...ux-foundation.org>,
"Paul E . McKenney" <paulmck@...ux.vnet.ibm.com>, "Eric W . Biederman" <ebiederm@...ssion.com>,
Oleg Nesterov <oleg@...hat.com>, Pavel Tikhomirov <ptikhomirov@...tuozzo.com>,
Ingo Molnar <mingo@...hat.com>, "H . Peter Anvin" <hpa@...or.com>, Paolo Bonzini <pbonzini@...hat.com>,
Rik van Riel <riel@...hat.com>, Kees Cook <keescook@...omium.org>,
Josh Poimboeuf <jpoimboe@...hat.com>, Borislav Petkov <bp@...en8.de>, Brian Gerst <brgerst@...il.com>,
"Kirill A . Shutemov" <kirill.shutemov@...ux.intel.com>,
Christian Borntraeger <borntraeger@...ibm.com>, Russell King <linux@...linux.org.uk>,
Will Deacon <will.deacon@....com>, Catalin Marinas <catalin.marinas@....com>,
Mark Rutland <mark.rutland@....com>, James Morse <james.morse@....com>,
linux-s390 <linux-s390@...r.kernel.org>, LKML <linux-kernel@...r.kernel.org>,
Linux API <linux-api@...r.kernel.org>, "the arch/x86 maintainers" <x86@...nel.org>,
"linux-arm-kernel@...ts.infradead.org" <linux-arm-kernel@...ts.infradead.org>,
Kernel Hardening <kernel-hardening@...ts.openwall.com>,
Linus Torvalds <torvalds@...ux-foundation.org>, Peter Zijlstra <a.p.zijlstra@...llo.nl>
Subject: Re: Re: [PATCH v9 1/4] syscalls: Verify address
limit before returning to user-mode
On Wed, May 10, 2017 at 1:14 AM, Christoph Hellwig <hch@...radead.org> wrote:
> On Wed, May 10, 2017 at 09:08:41AM +0100, Al Viro wrote:
>> On Wed, May 10, 2017 at 09:37:04AM +0200, Arnd Bergmann wrote:
>>
>> > > How about trying to remove all of them? If we could actually get rid
>> > > of all of them, we could drop the arch support, and we'd get faster,
>> > > simpler, shorter uaccess code throughout the kernel.
>>
>> BTW, not all get_user() under KERNEL_DS are plain loads. There is an
>> exception - probe_kernel_read().
>
> And various calls that looks like opencoded versions, e.g. drivers/dio
> or the ELF loader.
>
> But in the long run we'll just need a separate primitive for that,
> but that can wait until the set_fs calls outside the core code are
> gone.
I suspect that, on most arches, the primitive is called
__copy_from_user(). We could make the generic code do that except
where overridden.
Powered by blists - more mailing lists
Confused about mailing lists and their use?
Read about mailing lists on Wikipedia
and check out these
guidelines on proper formatting of your messages.
