From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3CFB0C432BE for ; Sat, 28 Aug 2021 01:53:22 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 8FBA560F91 for ; Sat, 28 Aug 2021 01:53:21 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 8FBA560F91 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id CEC138D0001; Fri, 27 Aug 2021 21:53:20 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id C74B26B0071; 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bh=IsOWHDvQ5UtBgx5GUnlq5SRzmvM9jdYHOtvAIirRgnY=; b=RnyBfCp8iYnHF+XA6o6OW2x3fz Zvj5cz8BfOeyy9VVeHFPOIaqZk19bwAnHXtDG6e3xJc4xvEcik5a5A2rGPorYkuQJqTp+soj2njts BuJOyCb7eZNSdWO91Dzo/7xI1fE5aOatYdV4AMusf/xo8vp74fDnLRjH2ZxTcIV8qAcFyf9AQcD1M RpUkC7GG0ovTBOz7qmRUyJR+eAMrKqeHWG4UwR+3gJjhxjr3GiO03QSEr6ZZQoXHg0LuS3+Csb/hL 6ai6gsEe+02oQYmsvhhmIxvz/Ugg/SnYCI6GD9+L3cJgfQAO6XNVmXYVsH3HEsUOCuLMM+JO7GUpF WUcD1PEw==; Received: from willy by casper.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1mJnR1-00FC17-3x; Sat, 28 Aug 2021 01:47:12 +0000 Date: Sat, 28 Aug 2021 02:47:03 +0100 From: Matthew Wilcox To: Suren Baghdasaryan Cc: akpm@linux-foundation.org, ccross@google.com, sumit.semwal@linaro.org, mhocko@suse.com, dave.hansen@intel.com, keescook@chromium.org, kirill.shutemov@linux.intel.com, vbabka@suse.cz, hannes@cmpxchg.org, corbet@lwn.net, viro@zeniv.linux.org.uk, rdunlap@infradead.org, kaleshsingh@google.com, peterx@redhat.com, rppt@kernel.org, peterz@infradead.org, catalin.marinas@arm.com, vincenzo.frascino@arm.com, chinwen.chang@mediatek.com, axelrasmussen@google.com, aarcange@redhat.com, jannh@google.com, apopple@nvidia.com, jhubbard@nvidia.com, yuzhao@google.com, will@kernel.org, fenghua.yu@intel.com, thunder.leizhen@huawei.com, hughd@google.com, feng.tang@intel.com, jgg@ziepe.ca, guro@fb.com, tglx@linutronix.de, krisman@collabora.com, chris.hyser@oracle.com, pcc@google.com, ebiederm@xmission.com, axboe@kernel.dk, legion@kernel.org, eb@emlix.com, songmuchun@bytedance.com, viresh.kumar@linaro.org, thomascedeno@google.com, sashal@kernel.org, cxfcosmos@gmail.com, linux@rasmusvillemoes.dk, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-doc@vger.kernel.org, linux-mm@kvack.org, kernel-team@android.com Subject: Re: [PATCH v8 2/3] mm: add a field to store names for private anonymous memory Message-ID: References: <20210827191858.2037087-1-surenb@google.com> <20210827191858.2037087-3-surenb@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210827191858.2037087-3-surenb@google.com> Authentication-Results: imf25.hostedemail.com; dkim=pass header.d=infradead.org header.s=casper.20170209 header.b=RnyBfCp8; dmarc=none; spf=none (imf25.hostedemail.com: domain of willy@infradead.org has no SPF policy when checking 90.155.50.34) smtp.mailfrom=willy@infradead.org X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: A7BF0B00008E X-Stat-Signature: bzco53gjfw6sr67sw7oy1ih1qxu188dg X-HE-Tag: 1630115599-902254 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: On Fri, Aug 27, 2021 at 12:18:57PM -0700, Suren Baghdasaryan wrote: > + anon_name = vma_anon_name(vma); > + if (anon_name) { > + seq_pad(m, ' '); > + seq_puts(m, "[anon:"); > + seq_write(m, anon_name, strlen(anon_name)); > + seq_putc(m, ']'); > + } ... > + case PR_SET_VMA_ANON_NAME: > + name = strndup_user((const char __user *)arg, > + ANON_VMA_NAME_MAX_LEN); > + > + if (IS_ERR(name)) > + return PTR_ERR(name); > + > + for (pch = name; *pch != '\0'; pch++) { > + if (!isprint(*pch)) { > + kfree(name); > + return -EINVAL; I think isprint() is too weak a check. For example, I would suggest forbidding the following characters: ':', ']', '[', ' '. Perhaps isalnum() would be better? (permit a-zA-Z0-9) I wouldn't necessarily be opposed to some punctuation characters, but let's avoid creating confusion. Do you happen to know which characters are actually in use today?