linux-mm.kvack.org archive mirror
 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>,
	Catalin Marinas <catalin.marinas@arm.com>,
	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>,
	kasan-dev@googlegroups.com, linux-mm@kvack.org,
	linux-kernel@vger.kernel.org
Cc: Qian Cai <cai@lca.pw>,
	Vincenzo Frascino <vincenzo.frascino@arm.com>,
	Kostya Serebryany <kcc@google.com>,
	Evgeniy Stepanov <eugenis@google.com>,
	Andrey Konovalov <andreyknvl@google.com>
Subject: [PATCH 2/4] kasan, slab: fix conflicts with CONFIG_HARDENED_USERCOPY
Date: Wed, 20 Feb 2019 13:45:27 +0100	[thread overview]
Message-ID: <9a5c0f958db10e69df5ff9f2b997866b56b7effc.1550602886.git.andreyknvl@google.com> (raw)
In-Reply-To: <9c4c3ce5ccfb894c7fe66d91de7c1da2787b4da4.1550602886.git.andreyknvl@google.com>

Similarly to 96fedce2 ("kasan: make tag based mode work with
CONFIG_HARDENED_USERCOPY"), we need to reset pointer tags in
__check_heap_object() in mm/slab.c before doing any pointer math.

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

diff --git a/mm/slab.c b/mm/slab.c
index 78eb8c5bf4e4..c84458281a88 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -4408,6 +4408,8 @@ void __check_heap_object(const void *ptr, unsigned long n, struct page *page,
 	unsigned int objnr;
 	unsigned long offset;
 
+	ptr = kasan_reset_tag(ptr);
+
 	/* Find and validate object. */
 	cachep = page->slab_cache;
 	objnr = obj_to_index(cachep, page, (void *)ptr);
-- 
2.21.0.rc0.258.g878e2cd30e-goog


  reply	other threads:[~2019-02-20 12:45 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-02-20 12:45 [PATCH 1/4] kasan: prevent tracing of tags.c Andrey Konovalov
2019-02-20 12:45 ` Andrey Konovalov [this message]
2019-02-20 12:45 ` [PATCH 3/4] kasan, slab: make freelist stored without tags Andrey Konovalov
2019-02-20 12:45 ` [PATCH 4/4] kasan, slab: remove redundant kasan_slab_alloc hooks Andrey Konovalov
2019-02-20 14:04 ` [PATCH 1/4] kasan: prevent tracing of tags.c Qian Cai

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=9a5c0f958db10e69df5ff9f2b997866b56b7effc.1550602886.git.andreyknvl@google.com \
    --to=andreyknvl@google.com \
    --cc=akpm@linux-foundation.org \
    --cc=aryabinin@virtuozzo.com \
    --cc=cai@lca.pw \
    --cc=catalin.marinas@arm.com \
    --cc=cl@linux.com \
    --cc=dvyukov@google.com \
    --cc=eugenis@google.com \
    --cc=glider@google.com \
    --cc=iamjoonsoo.kim@lge.com \
    --cc=kasan-dev@googlegroups.com \
    --cc=kcc@google.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=penberg@kernel.org \
    --cc=rientjes@google.com \
    --cc=vincenzo.frascino@arm.com \
    /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