From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: ARC-Seal: i=1; a=rsa-sha256; t=1522400882; cv=none; d=google.com; s=arc-20160816; b=daklbdHI4FmcJTU7HIUgr47dTOPjcEVgIxbFgMe1hpeDc3g3taQH1p/qAd4EVFpHxx Otx9HOjWCWtX4zPzOJdhC/CYCj/OP8TP94We8n5sxiwXxZlL2vJYtyMFpsrMmt7lXaWL puMK6AO0slVhE0Ht2kQjH9HwWGstTP4aqPCTSjC/9tjwpk6qeEgly51Wwe8QKPlGAV2K 1mERsesgYKJMIDZrDEsXxeTJMVyjZCh4Y7qCDcu5z56vxa0uXE87k4tk/U33LhfI1VlM /FxiY4RyR8ktrmdDOrBfXZ89PyygbF7jIFbwCirosQ1bEiXuzFV/XT2SK6a1rxQLG59I uFgA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=to:references:message-id:content-transfer-encoding:cc:date :in-reply-to:from:subject:mime-version:dkim-signature :arc-authentication-results; bh=ZTjxoqKaoobJFUevSLgPJQU741b1iW8H0MvOHx0z9s8=; b=hALKtA3Vz52npFGMO3rnjgQ2v/sGi4sN6+EEA2A7B3Bf4RxLyzHMdvAWnjh0TbZslg iIHpKBQktduZ8t2n9jO4E+Lro88MR8y0jHEEwI/D1xO8ymnkve1IJTl1BYPTikXvjlW+ sfy4j5qNAvUIFjEaT2xkGPFuutTq0fEWkIjhiBT3pRbkrsIuqA5Te5O0ydXNa5Q7Sp7d XCw99h+vaCIqA5HXg5art1gmAoSXWGCLpIwe/1tVRjzvIU5kpSPKD/27cP2EHNAa5b1v ymBOp5jE1WczfGCK7BsNmkL5RVxjss3qMq1GhXWzucXbG6kgeO2rdb6PTgozXJbdkUoR SUTA== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@gmail.com header.s=20161025 header.b=RouoAPah; spf=pass (google.com: domain of blackzert@gmail.com designates 209.85.220.65 as permitted sender) smtp.mailfrom=blackzert@gmail.com; dmarc=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com Authentication-Results: mx.google.com; dkim=pass header.i=@gmail.com header.s=20161025 header.b=RouoAPah; spf=pass (google.com: domain of blackzert@gmail.com designates 209.85.220.65 as permitted sender) smtp.mailfrom=blackzert@gmail.com; dmarc=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com X-Google-Smtp-Source: AIpwx4819IvCDJg/mTs2Ax4OcWGaODCSYvKwRadsg1AoBjgPwzfi7Txju4VQpU86PWklyO824cjPiA== Content-Type: text/plain; charset=utf-8 Mime-Version: 1.0 (Mac OS X Mail 11.2 \(3445.5.20\)) Subject: Re: [RFC PATCH v2 0/2] Randomization of address chosen by mmap. From: Ilya Smith In-Reply-To: <20180330075508.GA21798@amd> Date: Fri, 30 Mar 2018 12:07:58 +0300 Cc: rth@twiddle.net, ink@jurassic.park.msu.ru, mattst88@gmail.com, vgupta@synopsys.com, linux@armlinux.org.uk, tony.luck@intel.com, fenghua.yu@intel.com, jhogan@kernel.org, ralf@linux-mips.org, jejb@parisc-linux.org, Helge Deller , benh@kernel.crashing.org, paulus@samba.org, mpe@ellerman.id.au, schwidefsky@de.ibm.com, heiko.carstens@de.ibm.com, ysato@users.sourceforge.jp, dalias@libc.org, davem@davemloft.net, tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com, x86@kernel.org, nyc@holomorphy.com, viro@zeniv.linux.org.uk, arnd@arndb.de, gregkh@linuxfoundation.org, deepa.kernel@gmail.com, Michal Hocko , hughd@google.com, kstewart@linuxfoundation.org, pombredanne@nexb.com, akpm@linux-foundation.org, steve.capper@arm.com, punit.agrawal@arm.com, paul.burton@mips.com, aneesh.kumar@linux.vnet.ibm.com, npiggin@gmail.com, keescook@chromium.org, bhsharma@redhat.com, riel@redhat.com, nitin.m.gupta@oracle.com, kirill.shutemov@linux.intel.com, dan.j.williams@intel.com, jack@suse.cz, ross.zwisler@linux.intel.com, jglisse@redhat.com, willy@infradead.org, aarcange@redhat.com, oleg@redhat.com, linux-alpha@vger.kernel.org, linux-kernel@vger.kernel.org, linux-snps-arc@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-ia64@vger.kernel.org, linux-metag@vger.kernel.org, linux-mips@linux-mips.org, linux-parisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, sparclinux@vger.kernel.org, linux-mm@kvack.org Content-Transfer-Encoding: quoted-printable Message-Id: <95EECC28-7349-4FB4-88BF-26E4CF087A0B@gmail.com> References: <1521736598-12812-1-git-send-email-blackzert@gmail.com> <20180330075508.GA21798@amd> To: Pavel Machek X-Mailer: Apple Mail (2.3445.5.20) X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: =?utf-8?q?1595656488556903336?= X-GMAIL-MSGID: =?utf-8?q?1596353027728016155?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: Hi > On 30 Mar 2018, at 10:55, Pavel Machek wrote: >=20 > Hi! >=20 >> Current implementation doesn't randomize address returned by mmap. >> All the entropy ends with choosing mmap_base_addr at the process >> creation. After that mmap build very predictable layout of address >> space. It allows to bypass ASLR in many cases. This patch make >> randomization of address on any mmap call. >=20 > How will this interact with people debugging their application, and > getting different behaviours based on memory layout? >=20 > strace, strace again, get different results? >=20 Honestly I=E2=80=99m confused about your question. If the only one way = for debugging=20 application is to use predictable mmap behaviour, then something went = wrong in=20 this live and we should stop using computers at all. Thanks, Ilya