mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: "H. Peter Anvin" <hpa@zytor.com>
To: "Thomas Garnier" <thgarnie@google.com>,
	"Martin Schwidefsky" <schwidefsky@de.ibm.com>,
	"Heiko Carstens" <heiko.carstens@de.ibm.com>,
	"Dave Hansen" <dave.hansen@intel.com>,
	"Arnd Bergmann" <arnd@arndb.de>,
	"Thomas Gleixner" <tglx@linutronix.de>,
	"Al Viro" <viro@zeniv.linux.org.uk>,
	"David Howells" <dhowells@redhat.com>,
	"René Nyffenegger" <mail@renenyffenegger.ch>,
	"Andrew Morton" <akpm@linux-foundation.org>,
	"Paul E . McKenney" <paulmck@linux.vnet.ibm.com>,
	"Ingo Molnar" <mingo@kernel.org>,
	"Oleg Nesterov" <oleg@redhat.com>,
	"Stephen Smalley" <sds@tycho.nsa.gov>,
	"Pavel Tikhomirov" <ptikhomirov@virtuozzo.com>,
	"Ingo Molnar" <mingo@redhat.com>,
	"Andy Lutomirski" <luto@kernel.org>,
	"Paolo Bonzini" <pbonzini@redhat.com>,
	"Kees Cook" <keescook@chromium.org>,
	"Rik van Riel" <riel@redhat.com>,
	"Josh Poimboeuf" <jpoimboe@redhat.com>,
	"Borislav Petkov" <bp@alien8.de>,
	"Brian Gerst" <brgerst@gmail.com>,
	"Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>,
	"Christian Borntraeger" <borntraeger@de.ibm.com>,
	"Russell King" <linux@armlinux.org.uk>,
	"Will Deacon" <will.deacon@arm.com>,
	"Catalin Marinas" <catalin.marinas@arm.com>,
	"Mark Rutland" <mark.rutland@arm.com>,
	"James Morse" <james.morse@arm.com>
Cc: linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org,
	linux-api@vger.kernel.org, x86@kernel.org,
	linux-arm-kernel@lists.infradead.org,
	kernel-hardening@lists.openwall.com
Subject: Re: [PATCH v6 2/4] x86/syscalls: Specific usage of verify_pre_usermode_state
Date: Tue, 4 Apr 2017 11:11:03 -0700	[thread overview]
Message-ID: <b2b1b4fe-18ea-7643-09c0-312fd8f4b4d8@zytor.com> (raw)
In-Reply-To: <20170404174727.35478-2-thgarnie@google.com>

On 04/04/17 10:47, Thomas Garnier wrote:
> Implement specific usage of verify_pre_usermode_state for user-mode
> returns for x86.
> 
> Signed-off-by: Thomas Garnier <thgarnie@google.com>
>  
> +	/*
> +	 * If address limit is not based on user-mode, jump to slow path for
> +	 * additional security checks.
> +	 */
> +	movq	$TASK_SIZE_MAX, %rcx
> +	cmp	%rcx, TASK_addr_limit(%r11)
> +	jnz	1f
> +
>  	LOCKDEP_SYS_EXIT

Nitpick: use jne not jnz when comparing for equality.  Same instruction
but more readable.

	-hpa

  reply	other threads:[~2017-04-04 18:35 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-04-04 17:47 [PATCH v6 1/4] syscalls: Restore address limit after a syscall Thomas Garnier
2017-04-04 17:47 ` [PATCH v6 2/4] x86/syscalls: Specific usage of verify_pre_usermode_state Thomas Garnier
2017-04-04 18:11   ` H. Peter Anvin [this message]
2017-04-04 18:27   ` H. Peter Anvin
2017-04-04 18:54     ` Borislav Petkov
2017-04-04 19:21     ` Thomas Garnier
2017-04-04 22:34       ` H. Peter Anvin
2017-04-04 17:47 ` [PATCH v6 3/4] arm/syscalls: " Thomas Garnier
2017-04-04 17:47 ` [PATCH v6 4/4] arm64/syscalls: " Thomas Garnier
2017-04-05 14:22   ` Catalin Marinas
2017-04-05 14:36     ` Thomas Garnier
2017-04-05 17:49       ` Catalin Marinas
2017-04-05 18:14         ` Thomas Garnier
2017-04-07 16:11           ` Catalin Marinas

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=b2b1b4fe-18ea-7643-09c0-312fd8f4b4d8@zytor.com \
    --to=hpa@zytor.com \
    --cc=akpm@linux-foundation.org \
    --cc=arnd@arndb.de \
    --cc=borntraeger@de.ibm.com \
    --cc=bp@alien8.de \
    --cc=brgerst@gmail.com \
    --cc=catalin.marinas@arm.com \
    --cc=dave.hansen@intel.com \
    --cc=dhowells@redhat.com \
    --cc=heiko.carstens@de.ibm.com \
    --cc=james.morse@arm.com \
    --cc=jpoimboe@redhat.com \
    --cc=keescook@chromium.org \
    --cc=kernel-hardening@lists.openwall.com \
    --cc=kirill.shutemov@linux.intel.com \
    --cc=linux-api@vger.kernel.org \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-s390@vger.kernel.org \
    --cc=linux@armlinux.org.uk \
    --cc=luto@kernel.org \
    --cc=mail@renenyffenegger.ch \
    --cc=mark.rutland@arm.com \
    --cc=mingo@kernel.org \
    --cc=mingo@redhat.com \
    --cc=oleg@redhat.com \
    --cc=paulmck@linux.vnet.ibm.com \
    --cc=pbonzini@redhat.com \
    --cc=ptikhomirov@virtuozzo.com \
    --cc=riel@redhat.com \
    --cc=schwidefsky@de.ibm.com \
    --cc=sds@tycho.nsa.gov \
    --cc=tglx@linutronix.de \
    --cc=thgarnie@google.com \
    --cc=viro@zeniv.linux.org.uk \
    --cc=will.deacon@arm.com \
    --cc=x86@kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox

all inboxes | Powered by JetHome®