From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f199.google.com (mail-pf0-f199.google.com [209.85.192.199]) by kanga.kvack.org (Postfix) with ESMTP id 10B66828E1 for ; Thu, 23 Jun 2016 05:59:57 -0400 (EDT) Received: by mail-pf0-f199.google.com with SMTP id e189so162138364pfa.2 for ; Thu, 23 Jun 2016 02:59:57 -0700 (PDT) Received: from foss.arm.com (foss.arm.com. [217.140.101.70]) by mx.google.com with ESMTP id a8si6039024pfj.35.2016.06.23.02.59.56 for ; Thu, 23 Jun 2016 02:59:56 -0700 (PDT) Date: Thu, 23 Jun 2016 10:59:51 +0100 From: Catalin Marinas Subject: Re: [PATCH] mm: prevent KASAN false positives in kmemleak Message-ID: <20160623095951.GH6521@e104818-lin.cambridge.arm.com> References: <1466617631-68387-1-git-send-email-dvyukov@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1466617631-68387-1-git-send-email-dvyukov@google.com> Sender: owner-linux-mm@kvack.org List-ID: To: Dmitry Vyukov Cc: linux-mm@kvack.org, akpm@linux-foundation.org, linux-kernel@vger.kernel.org, ryabinin.a.a@gmail.com, kasan-dev@googlegroups.com, glider@google.com On Wed, Jun 22, 2016 at 07:47:11PM +0200, Dmitry Vyukov wrote: > When kmemleak dumps contents of leaked objects it reads whole > objects regardless of user-requested size. This upsets KASAN. > Disable KASAN checks around object dump. > > Signed-off-by: Dmitry Vyukov > --- > mm/kmemleak.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/mm/kmemleak.c b/mm/kmemleak.c > index e642992..04320d3 100644 > --- a/mm/kmemleak.c > +++ b/mm/kmemleak.c > @@ -307,8 +307,10 @@ static void hex_dump_object(struct seq_file *seq, > len = min_t(size_t, object->size, HEX_MAX_LINES * HEX_ROW_SIZE); > > seq_printf(seq, " hex dump (first %zu bytes):\n", len); > + kasan_disable_current(); > seq_hex_dump(seq, " ", DUMP_PREFIX_NONE, HEX_ROW_SIZE, > HEX_GROUP_SIZE, ptr, len, HEX_ASCII); > + kasan_enable_current(); > } Acked-by: Catalin Marinas -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org