LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
From: Kees Cook <keescook@chromium.org>
To: akpm@linux-foundation.org
Cc: "Kees Cook" <keescook@chromium.org>,
	linux-kernel@vger.kernel.org,
	"Hector Marco-Gisbert" <hecmargi@upv.es>,
	"Ismael Ripoll" <iripoll@upv.es>,
	"Russell King" <linux@arm.linux.org.uk>,
	"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>,
	"Min-Hua Chen" <orca.chen@gmail.com>,
	"Dan McGee" <dpmcgee@gmail.com>,
	"Yann Droneaud" <ydroneaud@opteya.com>,
	"Paul Burton" <paul.burton@imgtec.com>,
	"Alex Smith" <alex@alex-smith.me.uk>,
	"Markos Chandras" <markos.chandras@imgtec.com>,
	"Vineeth Vijayan" <vvijayan@mvista.com>,
	"Jeff Bailey" <jeffbailey@google.com>,
	"Michael Holzheu" <holzheu@linux.vnet.ibm.com>,
	"Ben Hutchings" <ben@decadent.org.uk>,
	"Behan Webster" <behanw@converseincode.com>,
	"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: [PATCH v3 08/10] s390: redefine randomize_et_dyn for ELF_ET_DYN_BASE
Date: Tue,  3 Mar 2015 18:10:23 -0800	[thread overview]
Message-ID: <1425435025-30284-9-git-send-email-keescook@chromium.org> (raw)
In-Reply-To: <1425435025-30284-1-git-send-email-keescook@chromium.org>

In preparation for moving ET_DYN randomization into the ELF loader (which
requires a static ELF_ET_DYN_BASE), this redefines s390's existing ET_DYN
randomization in a call to arch_mmap_rnd(). This refactoring results in
the same ET_DYN randomization on s390.

Signed-off-by: Kees Cook <keescook@chromium.org>
---
 arch/s390/include/asm/elf.h |  8 +++++---
 arch/s390/mm/mmap.c         | 11 ++---------
 2 files changed, 7 insertions(+), 12 deletions(-)

diff --git a/arch/s390/include/asm/elf.h b/arch/s390/include/asm/elf.h
index c9df40b5c0ac..2e63de8aac7c 100644
--- a/arch/s390/include/asm/elf.h
+++ b/arch/s390/include/asm/elf.h
@@ -161,10 +161,12 @@ extern unsigned int vdso_enabled;
 /* This is the location that an ET_DYN program is loaded if exec'ed.  Typical
    use of this is to invoke "./ld.so someprog" to test out a new version of
    the loader.  We need to make sure that it is out of the way of the program
-   that it will "exec", and that there is sufficient room for the brk.  */
-
+   that it will "exec", and that there is sufficient room for the brk. 64-bit
+   tasks are aligned to 4GB. */
 extern unsigned long randomize_et_dyn(void);
-#define ELF_ET_DYN_BASE		randomize_et_dyn()
+#define ELF_ET_DYN_BASE (randomize_et_dyn() + (is_32bit_task() ? \
+				(STACK_TOP / 3 * 2) : \
+				(STACK_TOP / 3 * 2) & ~((1UL << 32) - 1)))
 
 /* This yields a mask that user programs can use to figure out what
    instruction set this CPU supports. */
diff --git a/arch/s390/mm/mmap.c b/arch/s390/mm/mmap.c
index a94504d99c47..8c11536f972d 100644
--- a/arch/s390/mm/mmap.c
+++ b/arch/s390/mm/mmap.c
@@ -179,17 +179,10 @@ arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
 
 unsigned long randomize_et_dyn(void)
 {
-	unsigned long base;
-
-	base = STACK_TOP / 3 * 2;
-	if (!is_32bit_task())
-		/* Align to 4GB */
-		base &= ~((1UL << 32) - 1);
-
 	if (current->flags & PF_RANDOMIZE)
-		base += arch_mmap_rnd();
+		return arch_mmap_rnd();
 
-	return base;
+	return 0UL;
 }
 
 #ifndef CONFIG_64BIT
-- 
1.9.1


  parent reply	other threads:[~2015-03-04  2:14 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-03-04  2:10 [PATCH v3 0/10] split ET_DYN ASLR from mmap ASLR Kees Cook
2015-03-04  2:10 ` [PATCH v3 01/10] arm: factor out mmap ASLR into mmap_rnd Kees Cook
2015-03-04  2:10 ` [PATCH v3 02/10] x86: standardize mmap_rnd() usage Kees Cook
2015-03-04  2:10 ` [PATCH v3 03/10] arm64: " Kees Cook
2015-03-04  2:10 ` [PATCH v3 04/10] mips: extract logic for mmap_rnd() Kees Cook
2015-03-04  2:10 ` [PATCH v3 05/10] powerpc: standardize mmap_rnd() usage Kees Cook
2015-03-04  2:10 ` [PATCH v3 06/10] s390: " Kees Cook
2015-03-04  2:10 ` [PATCH v3 07/10] mm: expose arch_mmap_rnd when available Kees Cook
2015-03-04  2:10 ` Kees Cook [this message]
2015-03-04  2:10 ` [PATCH v3 09/10] mm: split ET_DYN ASLR from mmap ASLR Kees Cook
2015-03-04  2:10 ` [PATCH v3 10/10] mm: fold arch_randomize_brk into ARCH_HAS_ELF_RANDOMIZE Kees Cook
2015-03-09 16:19 ` [PATCH v3 0/10] split ET_DYN ASLR from mmap ASLR Russell King - ARM Linux
2015-03-09 18:06   ` 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=1425435025-30284-9-git-send-email-keescook@chromium.org \
    --to=keescook@chromium.org \
    --cc=a.ryabinin@samsung.com \
    --cc=achandran@mvista.com \
    --cc=akpm@linux-foundation.org \
    --cc=alex@alex-smith.me.uk \
    --cc=behanw@converseincode.com \
    --cc=ben@decadent.org.uk \
    --cc=benh@kernel.crashing.org \
    --cc=catalin.marinas@arm.com \
    --cc=dave.long@linaro.org \
    --cc=dl9pf@gmx.de \
    --cc=dpmcgee@gmail.com \
    --cc=hecmargi@upv.es \
    --cc=heiko.carstens@de.ibm.com \
    --cc=holzheu@linux.vnet.ibm.com \
    --cc=iripoll@upv.es \
    --cc=jeffbailey@google.com \
    --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=linux@arm.linux.org.uk \
    --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 v3 08/10] s390: redefine randomize_et_dyn for ELF_ET_DYN_BASE' \
    /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).