LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
From: Andrey Konovalov <andreyknvl@google.com>
To: "Andrey Ryabinin" <aryabinin@virtuozzo.com>,
	"Alexander Potapenko" <glider@google.com>,
	"Dmitry Vyukov" <dvyukov@google.com>,
	"Jonathan Corbet" <corbet@lwn.net>,
	"Catalin Marinas" <catalin.marinas@arm.com>,
	"Will Deacon" <will.deacon@arm.com>,
	"Christopher Li" <sparse@chrisli.org>,
	"Christoph Lameter" <cl@linux.com>,
	"Pekka Enberg" <penberg@kernel.org>,
	"David Rientjes" <rientjes@google.com>,
	"Joonsoo Kim" <iamjoonsoo.kim@lge.com>,
	"Andrew Morton" <akpm@linux-foundation.org>,
	"Masahiro Yamada" <yamada.masahiro@socionext.com>,
	"Michal Marek" <michal.lkml@markovi.net>,
	"Andrey Konovalov" <andreyknvl@google.com>,
	"Mark Rutland" <mark.rutland@arm.com>,
	"Nick Desaulniers" <ndesaulniers@google.com>,
	"Yury Norov" <ynorov@caviumnetworks.com>,
	"Marc Zyngier" <marc.zyngier@arm.com>,
	"Kristina Martsenko" <kristina.martsenko@arm.com>,
	"Suzuki K Poulose" <suzuki.poulose@arm.com>,
	"Punit Agrawal" <punit.agrawal@arm.com>,
	"Dave Martin" <dave.martin@arm.com>,
	"Ard Biesheuvel" <ard.biesheuvel@linaro.org>,
	"James Morse" <james.morse@arm.com>,
	"Michael Weiser" <michael.weiser@gmx.de>,
	"Julien Thierry" <julien.thierry@arm.com>,
	"Tyler Baicar" <tbaicar@codeaurora.org>,
	"Eric W . Biederman" <ebiederm@xmission.com>,
	"Thomas Gleixner" <tglx@linutronix.de>,
	"Ingo Molnar" <mingo@kernel.org>,
	"Kees Cook" <keescook@chromium.org>,
	"Sandipan Das" <sandipan@linux.vnet.ibm.com>,
	"David Woodhouse" <dwmw@amazon.co.uk>,
	"Paul Lawrence" <paullawrence@google.com>,
	"Herbert Xu" <herbert@gondor.apana.org.au>,
	"Josh Poimboeuf" <jpoimboe@redhat.com>,
	"Geert Uytterhoeven" <geert@linux-m68k.org>,
	"Tom Lendacky" <thomas.lendacky@amd.com>,
	"Arnd Bergmann" <arnd@arndb.de>,
	"Dan Williams" <dan.j.williams@intel.com>,
	"Michal Hocko" <mhocko@suse.com>, "Jan Kara" <jack@suse.cz>,
	"Ross Zwisler" <ross.zwisler@linux.intel.com>,
	"Jérôme Glisse" <jglisse@redhat.com>,
	"Matthew Wilcox" <mawilcox@microsoft.com>,
	"Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>,
	"Souptick Joarder" <jrdr.linux@gmail.com>,
	"Hugh Dickins" <hughd@google.com>,
	"Davidlohr Bueso" <dave@stgolabs.net>,
	"Greg Kroah-Hartman" <gregkh@linuxfoundation.org>,
	"Philippe Ombredanne" <pombredanne@nexb.com>,
	"Kate Stewart" <kstewart@linuxfoundation.org>,
	"Laura Abbott" <labbott@redhat.com>,
	"Boris Brezillon" <boris.brezillon@bootlin.com>,
	"Vlastimil Babka" <vbabka@suse.cz>,
	"Pintu Agarwal" <pintu.ping@gmail.com>,
	"Doug Berger" <opendmb@gmail.com>,
	"Anshuman Khandual" <khandual@linux.vnet.ibm.com>,
	"Mike Rapoport" <rppt@linux.vnet.ibm.com>,
	"Mel Gorman" <mgorman@suse.de>,
	"Pavel Tatashin" <pasha.tatashin@oracle.com>,
	"Tetsuo Handa" <penguin-kernel@I-love.SAKURA.ne.jp>,
	kasan-dev@googlegroups.com, linux-doc@vger.kernel.org,
	linux-kernel@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org,
	linux-sparse@vger.kernel.org, linux-mm@kvack.org,
	linux-kbuild@vger.kernel.org
Cc: Kostya Serebryany <kcc@google.com>,
	Evgeniy Stepanov <eugenis@google.com>,
	Lee Smith <Lee.Smith@arm.com>,
	Ramana Radhakrishnan <Ramana.Radhakrishnan@arm.com>,
	Jacob Bramley <Jacob.Bramley@arm.com>,
	Ruben Ayrapetyan <Ruben.Ayrapetyan@arm.com>,
	Kees Cook <keescook@google.com>, Jann Horn <jannh@google.com>,
	Mark Brand <markbrand@google.com>,
	Chintan Pandya <cpandya@codeaurora.org>
Subject: [PATCH v1 10/16] khwasan, mm: perform untagged pointers comparison in krealloc
Date: Tue,  8 May 2018 19:20:56 +0200	[thread overview]
Message-ID: <94f6719e7e696977de00354f8201581a8f9108d3.1525798754.git.andreyknvl@google.com> (raw)
In-Reply-To: <cover.1525798753.git.andreyknvl@google.com>
In-Reply-To: <cover.1525798753.git.andreyknvl@google.com>

The krealloc function checks where the same buffer was reused or a new one
allocated by comparing kernel pointers. KHWASAN changes memory tag on the
krealloc'ed chunk of memory and therefore also changes the pointer tag of
the returned pointer. Therefore we need to perform comparison on untagged
(with tags reset) pointers to check whether it's the same memory region or
not.

Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
---
 mm/slab_common.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mm/slab_common.c b/mm/slab_common.c
index 0582004351c4..451b094b8c5b 100644
--- a/mm/slab_common.c
+++ b/mm/slab_common.c
@@ -1478,7 +1478,7 @@ void *krealloc(const void *p, size_t new_size, gfp_t flags)
 	}
 
 	ret = __do_krealloc(p, new_size, flags);
-	if (ret && p != ret)
+	if (ret && khwasan_reset_tag(p) != khwasan_reset_tag(ret))
 		kfree(p);
 
 	return ret;
-- 
2.17.0.441.gb46fe60e1d-goog

  parent reply	other threads:[~2018-05-08 17:20 UTC|newest]

Thread overview: 25+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-05-08 17:20 [PATCH v1 00/16] khwasan: kernel hardware assisted address sanitizer Andrey Konovalov
2018-05-08 17:20 ` [PATCH v1 01/16] khwasan, mm: change kasan hooks signatures Andrey Konovalov
2018-05-14 16:56   ` Andrey Ryabinin
2018-05-08 17:20 ` [PATCH v1 02/16] khwasan: move common kasan and khwasan code to common.c Andrey Konovalov
2018-05-15 13:28   ` Andrey Ryabinin
2018-05-08 17:20 ` [PATCH v1 03/16] khwasan: add CONFIG_KASAN_GENERIC and CONFIG_KASAN_HW Andrey Konovalov
2018-05-14 16:57   ` Andrey Ryabinin
2018-05-08 17:20 ` [PATCH v1 04/16] khwasan, arm64: adjust shadow size for CONFIG_KASAN_HW Andrey Konovalov
2018-05-08 17:20 ` [PATCH v1 05/16] khwasan: initialize shadow to 0xff Andrey Konovalov
2018-05-08 17:20 ` [PATCH v1 06/16] khwasan, arm64: untag virt address in __kimg_to_phys Andrey Konovalov
2018-05-08 17:20 ` [PATCH v1 07/16] khwasan, arm64: fix up fault handling logic Andrey Konovalov
2018-05-08 17:20 ` [PATCH v1 08/16] khwasan: add tag related helper functions Andrey Konovalov
2018-05-14 16:58   ` Andrey Ryabinin
2018-05-08 17:20 ` [PATCH v1 09/16] khwasan, arm64: enable top byte ignore for the kernel Andrey Konovalov
2018-05-08 17:20 ` Andrey Konovalov [this message]
2018-05-08 17:20 ` [PATCH v1 11/16] khwasan: split out kasan_report.c from report.c Andrey Konovalov
2018-05-08 17:20 ` [PATCH v1 12/16] khwasan: add bug reporting routines Andrey Konovalov
2018-05-08 17:20 ` [PATCH v1 13/16] khwasan: add hooks implementation Andrey Konovalov
2018-05-15 13:13   ` Andrey Ryabinin
2018-05-08 17:21 ` [PATCH v1 14/16] khwasan, arm64: add brk handler for inline instrumentation Andrey Konovalov
2018-05-08 17:21 ` [PATCH v1 15/16] khwasan, mm, arm64: tag non slab memory allocated via pagealloc Andrey Konovalov
2018-05-15 14:06   ` Andrey Ryabinin
2018-05-08 17:21 ` [PATCH v1 16/16] khwasan: update kasan documentation Andrey Konovalov
2018-05-09  5:26   ` Mike Rapoport
2018-05-09 12:13     ` Andrey Konovalov

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=94f6719e7e696977de00354f8201581a8f9108d3.1525798754.git.andreyknvl@google.com \
    --to=andreyknvl@google.com \
    --cc=Jacob.Bramley@arm.com \
    --cc=Lee.Smith@arm.com \
    --cc=Ramana.Radhakrishnan@arm.com \
    --cc=Ruben.Ayrapetyan@arm.com \
    --cc=akpm@linux-foundation.org \
    --cc=ard.biesheuvel@linaro.org \
    --cc=arnd@arndb.de \
    --cc=aryabinin@virtuozzo.com \
    --cc=boris.brezillon@bootlin.com \
    --cc=catalin.marinas@arm.com \
    --cc=cl@linux.com \
    --cc=corbet@lwn.net \
    --cc=cpandya@codeaurora.org \
    --cc=dan.j.williams@intel.com \
    --cc=dave.martin@arm.com \
    --cc=dave@stgolabs.net \
    --cc=dvyukov@google.com \
    --cc=dwmw@amazon.co.uk \
    --cc=ebiederm@xmission.com \
    --cc=eugenis@google.com \
    --cc=geert@linux-m68k.org \
    --cc=glider@google.com \
    --cc=gregkh@linuxfoundation.org \
    --cc=herbert@gondor.apana.org.au \
    --cc=hughd@google.com \
    --cc=iamjoonsoo.kim@lge.com \
    --cc=jack@suse.cz \
    --cc=james.morse@arm.com \
    --cc=jannh@google.com \
    --cc=jglisse@redhat.com \
    --cc=jpoimboe@redhat.com \
    --cc=jrdr.linux@gmail.com \
    --cc=julien.thierry@arm.com \
    --cc=kasan-dev@googlegroups.com \
    --cc=kcc@google.com \
    --cc=keescook@chromium.org \
    --cc=keescook@google.com \
    --cc=khandual@linux.vnet.ibm.com \
    --cc=kirill.shutemov@linux.intel.com \
    --cc=kristina.martsenko@arm.com \
    --cc=kstewart@linuxfoundation.org \
    --cc=labbott@redhat.com \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-doc@vger.kernel.org \
    --cc=linux-kbuild@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=linux-sparse@vger.kernel.org \
    --cc=marc.zyngier@arm.com \
    --cc=mark.rutland@arm.com \
    --cc=markbrand@google.com \
    --cc=mawilcox@microsoft.com \
    --cc=mgorman@suse.de \
    --cc=mhocko@suse.com \
    --cc=michael.weiser@gmx.de \
    --cc=michal.lkml@markovi.net \
    --cc=mingo@kernel.org \
    --cc=ndesaulniers@google.com \
    --cc=opendmb@gmail.com \
    --cc=pasha.tatashin@oracle.com \
    --cc=paullawrence@google.com \
    --cc=penberg@kernel.org \
    --cc=penguin-kernel@I-love.SAKURA.ne.jp \
    --cc=pintu.ping@gmail.com \
    --cc=pombredanne@nexb.com \
    --cc=punit.agrawal@arm.com \
    --cc=rientjes@google.com \
    --cc=ross.zwisler@linux.intel.com \
    --cc=rppt@linux.vnet.ibm.com \
    --cc=sandipan@linux.vnet.ibm.com \
    --cc=sparse@chrisli.org \
    --cc=suzuki.poulose@arm.com \
    --cc=tbaicar@codeaurora.org \
    --cc=tglx@linutronix.de \
    --cc=thomas.lendacky@amd.com \
    --cc=vbabka@suse.cz \
    --cc=will.deacon@arm.com \
    --cc=yamada.masahiro@socionext.com \
    --cc=ynorov@caviumnetworks.com \
    --subject='Re: [PATCH v1 10/16] khwasan, mm: perform untagged pointers comparison in krealloc' \
    /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).