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Thu, 09 Sep 2021 20:19:02 -0700 (PDT) Received: from [10.86.116.180] ([139.177.225.230]) by smtp.gmail.com with ESMTPSA id q12sm3488773pfj.153.2021.09.09.20.18.58 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 09 Sep 2021 20:19:01 -0700 (PDT) Subject: Re: [External] Re: [patch 079/147] fs/proc/kcore.c: add mmap interface To: Linus Torvalds Cc: Andrew Morton , Alexey Dobriyan , chenying.kernel@bytedance.com, Linux-MM , mm-commits@vger.kernel.org, Mike Rapoport , Muchun Song , zhouchengming@bytedance.com, zhengqi.arch@bytedance.com References: <20210907195226.14b1d22a07c085b22968b933@linux-foundation.org> <20210908025730.S88ylmikU%akpm@linux-foundation.org> From: Feng Zhou Message-ID: Date: Fri, 10 Sep 2021 11:18:54 +0800 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:78.0) Gecko/20100101 Thunderbird/78.14.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Authentication-Results: imf09.hostedemail.com; dkim=pass header.d=bytedance-com.20150623.gappssmtp.com header.s=20150623 header.b=BY+b79Gk; spf=pass (imf09.hostedemail.com: domain of zhoufeng.zf@bytedance.com designates 209.85.216.53 as permitted sender) smtp.mailfrom=zhoufeng.zf@bytedance.com; dmarc=pass (policy=none) header.from=bytedance.com X-Stat-Signature: kbnksbmi6cfgq358s6kza487hdmdw3mt X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: C9BEC3000104 X-HE-Tag: 1631243943-83542 Content-Transfer-Encoding: quoted-printable X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: =E5=9C=A8 2021/9/10 =E4=B8=8A=E5=8D=881:34, Linus Torvalds =E5=86=99=E9=81= =93: > On Thu, Sep 9, 2021 at 10:32 AM Linus Torvalds > wrote: >> This is basically a very dangerous interface. The fact that it is >> read-only doesn't change that at all. > Just to clarify - we've done dangerous interfaces in the past. We > probably have tons of them still that I haven't even thought about, > and I think I can hear somebody sniggering from miles away about > various bugs that cause much more obvious security holes that I didn't > think of. > > But the fact that we might have other holes that can be misused, > doesn't mean we have to add new ones that seem to be almost designed > for misuse. > > Linus Ok, got it.