LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
From: Russell King - ARM Linux <linux@arm.linux.org.uk>
To: Kees Cook <keescook@chromium.org>
Cc: akpm@linux-foundation.org, linux-kernel@vger.kernel.org,
	"Catalin Marinas" <catalin.marinas@arm.com>,
	"Will Deacon" <will.deacon@arm.com>,
	"Ralf Baechle" <ralf@linux-mips.org>,
	"Benjamin Herrenschmidt" <benh@kernel.crashing.org>,
	"Paul Mackerras" <paulus@samba.org>,
	"Michael Ellerman" <mpe@ellerman.id.au>,
	"Martin Schwidefsky" <schwidefsky@de.ibm.com>,
	"Heiko Carstens" <heiko.carstens@de.ibm.com>,
	linux390@de.ibm.com, x86@kernel.org,
	"Alexander Viro" <viro@zeniv.linux.org.uk>,
	"Oleg Nesterov" <oleg@redhat.com>,
	"Andy Lutomirski" <luto@amacapital.net>,
	"David A. Long" <dave.long@linaro.org>,
	"Andrey Ryabinin" <a.ryabinin@samsung.com>,
	"Arun Chandran" <achandran@mvista.com>,
	"Yann Droneaud" <ydroneaud@opteya.com>,
	"Min-Hua Chen" <orca.chen@gmail.com>,
	"Paul Burton" <paul.burton@imgtec.com>,
	"Alex Smith" <alex@alex-smith.me.uk>,
	"Markos Chandras" <markos.chandras@imgtec.com>,
	"Jeff Bailey" <jeffbailey@google.com>,
	"Vineeth Vijayan" <vvijayan@mvista.com>,
	"Michael Holzheu" <holzheu@linux.vnet.ibm.com>,
	"Ben Hutchings" <ben@decadent.org.uk>,
	"Hector Marco-Gisbert" <hecmargi@upv.es>,
	"Borislav Petkov" <bp@suse.de>, "Jan-Simon Möller" <dl9pf@gmx.de>,
	linux-arm-kernel@lists.infradead.org, linux-mips@linux-mips.org,
	linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org,
	linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH 1/5] arm: factor out mmap ASLR into mmap_rnd
Date: Mon, 9 Mar 2015 14:48:31 +0000	[thread overview]
Message-ID: <20150309144831.GM8656@n2100.arm.linux.org.uk> (raw)
In-Reply-To: <1425341988-1599-2-git-send-email-keescook@chromium.org>

On Mon, Mar 02, 2015 at 04:19:44PM -0800, Kees Cook wrote:
> In preparation for exporting per-arch mmap randomization functions,
> this moves the ASLR calculations for mmap on ARM into a separate routine.
> 
> Signed-off-by: Kees Cook <keescook@chromium.org>

Looks fine, thanks.

Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>

> ---
>  arch/arm/mm/mmap.c | 13 ++++++++++---
>  1 file changed, 10 insertions(+), 3 deletions(-)
> 
> diff --git a/arch/arm/mm/mmap.c b/arch/arm/mm/mmap.c
> index 5e85ed371364..0f8bc158f2c6 100644
> --- a/arch/arm/mm/mmap.c
> +++ b/arch/arm/mm/mmap.c
> @@ -169,14 +169,21 @@ arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
>  	return addr;
>  }
>  
> -void arch_pick_mmap_layout(struct mm_struct *mm)
> +static unsigned long mmap_rnd(void)
>  {
> -	unsigned long random_factor = 0UL;
> +	unsigned long rnd = 0UL;
>  
>  	/* 8 bits of randomness in 20 address space bits */
>  	if ((current->flags & PF_RANDOMIZE) &&
>  	    !(current->personality & ADDR_NO_RANDOMIZE))
> -		random_factor = (get_random_int() % (1 << 8)) << PAGE_SHIFT;
> +		rnd = (get_random_int() % (1 << 8)) << PAGE_SHIFT;
> +
> +	return rnd;
> +}
> +
> +void arch_pick_mmap_layout(struct mm_struct *mm)
> +{
> +	unsigned long random_factor = mmap_rnd();
>  
>  	if (mmap_is_legacy()) {
>  		mm->mmap_base = TASK_UNMAPPED_BASE + random_factor;
> -- 
> 1.9.1
> 

-- 
FTTC broadband for 0.8mile line: currently at 10.5Mbps down 400kbps up
according to speedtest.net.

  reply	other threads:[~2015-03-09 14:49 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-03-03  0:19 [PATCH v2 0/5] split ET_DYN ASLR from mmap ASLR Kees Cook
2015-03-03  0:19 ` [PATCH 1/5] arm: factor out mmap ASLR into mmap_rnd Kees Cook
2015-03-09 14:48   ` Russell King - ARM Linux [this message]
2015-03-03  0:19 ` [PATCH 2/5] mm: expose arch_mmap_rnd when available Kees Cook
2015-03-09 14:49   ` Russell King - ARM Linux
2015-03-03  0:19 ` [PATCH 3/5] mm: move randomize_et_dyn into ELF_ET_DYN_BASE Kees Cook
2015-03-03  0:19 ` [PATCH 4/5] mm: split ET_DYN ASLR from mmap ASLR Kees Cook
2015-03-04  4:16   ` Michael Ellerman
2015-03-04 21:13     ` Kees Cook
2015-03-04 23:56       ` Michael Ellerman
2015-03-09 15:13   ` Russell King - ARM Linux
2015-03-03  0:19 ` [PATCH 5/5] mm: fold arch_randomize_brk into ARCH_HAS_ELF_RANDOMIZE Kees Cook
2015-03-09 14:51   ` Russell King - ARM Linux
2015-03-03  7:31 ` [PATCH v2 0/5] split ET_DYN ASLR from mmap ASLR Ingo Molnar
2015-03-03 18:03   ` Kees Cook
2015-03-04  4:20     ` Ingo Molnar
2015-03-09 15:15 ` Russell King - ARM Linux
  -- strict thread matches above, loose matches on Subject: below --
2015-02-27  3:07 [PATCH " Kees Cook
2015-02-27  3:07 ` [PATCH 1/5] arm: factor out mmap ASLR into mmap_rnd Kees Cook

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=20150309144831.GM8656@n2100.arm.linux.org.uk \
    --to=linux@arm.linux.org.uk \
    --cc=a.ryabinin@samsung.com \
    --cc=achandran@mvista.com \
    --cc=akpm@linux-foundation.org \
    --cc=alex@alex-smith.me.uk \
    --cc=ben@decadent.org.uk \
    --cc=benh@kernel.crashing.org \
    --cc=bp@suse.de \
    --cc=catalin.marinas@arm.com \
    --cc=dave.long@linaro.org \
    --cc=dl9pf@gmx.de \
    --cc=hecmargi@upv.es \
    --cc=heiko.carstens@de.ibm.com \
    --cc=holzheu@linux.vnet.ibm.com \
    --cc=jeffbailey@google.com \
    --cc=keescook@chromium.org \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mips@linux-mips.org \
    --cc=linux-s390@vger.kernel.org \
    --cc=linux390@de.ibm.com \
    --cc=linuxppc-dev@lists.ozlabs.org \
    --cc=luto@amacapital.net \
    --cc=markos.chandras@imgtec.com \
    --cc=mpe@ellerman.id.au \
    --cc=oleg@redhat.com \
    --cc=orca.chen@gmail.com \
    --cc=paul.burton@imgtec.com \
    --cc=paulus@samba.org \
    --cc=ralf@linux-mips.org \
    --cc=schwidefsky@de.ibm.com \
    --cc=viro@zeniv.linux.org.uk \
    --cc=vvijayan@mvista.com \
    --cc=will.deacon@arm.com \
    --cc=x86@kernel.org \
    --cc=ydroneaud@opteya.com \
    --subject='Re: [PATCH 1/5] arm: factor out mmap ASLR into mmap_rnd' \
    /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

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).