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=-23.6 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_IN_DEF_DKIM_WL autolearn=unavailable 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 887A6C433DB for ; Sat, 9 Jan 2021 01:03:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6044B23AAA for ; Sat, 9 Jan 2021 01:03:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726443AbhAIBDO (ORCPT ); Fri, 8 Jan 2021 20:03:14 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43156 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726432AbhAIBDN (ORCPT ); Fri, 8 Jan 2021 20:03:13 -0500 Received: from mail-pj1-x1032.google.com (mail-pj1-x1032.google.com [IPv6:2607:f8b0:4864:20::1032]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4AA83C061574 for ; Fri, 8 Jan 2021 17:02:33 -0800 (PST) Received: by mail-pj1-x1032.google.com with SMTP id p12so4562029pju.5 for ; Fri, 08 Jan 2021 17:02:33 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:from:to:cc:subject:in-reply-to:message-id:references :mime-version; bh=oo3kBdaJhl9ExjF4SDMLaMM4Wh9mmEWqkI73c+HY9rM=; b=h4uxMGH9w0WgecwaPG6ABWiu4gFq2c1ZeVLGyUhBIRXGGCY7Dq+QZyBHoVP28cz2SU Qw/QLxB2y64egxksBjw8ECQEzPtCEA5K6wi7AS1QWrFqxE4C7C4U1uX+HVKlfnSqnsuL 0RoGTArPQgSJgiuEBwCZUWEJxzsWs+dlJNAftBD37m4woo9XkfsFk/MuwCwjyg+WvYp2 Dv0ZtL1OFx04SQ7Q7d/tPRSqnHmmKbCbbr7OwDC1MXxc7W/+PZgSPPClzVztxFi4yMus t0irObY9h7pVoguKlD54L+WsUTJfOtKqCLmunaaF6g5oS81dy0wZfYjx1y/CiU6t2dDR cBUA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:in-reply-to:message-id :references:mime-version; bh=oo3kBdaJhl9ExjF4SDMLaMM4Wh9mmEWqkI73c+HY9rM=; b=B1Lx1fHkiXyJ2AUD9N444l2ABXlJ6Rn8FcLrKMVkA1fxBzH/zi40HhpcKj5AORnws/ tV8YCCX1IzUkPoveh8CcHUqgWYKb4spXlJomNg30TUQ9gAkJcb5eFiMwOg5di+85yTdt /fuRBtd7Z2bseraysSF5dEwEYSghsyIUohdaQ2tPhYiBoOMRefugURUMk7MwMgvQPQ/e 0Qc+lJEwLwsAwRpxca0MAF+z+fJLoQyUlQKky9mWTXvDFuJYbiXESsl1D6pb94E0i8wN wFJkoh8KzKBKdvkQNnNaxP1lu0LeraK0P/apZ0GVB0mA2WjyL5bvexyskRajjhpCpvif zuUw== X-Gm-Message-State: AOAM530K4QjCblw5XzvKLoIvnRnWkrYONSfK16yfXcFTqp2/fnOT4j5D xYy5iAvkK1wbFCLZVFC6XTLUOA== X-Google-Smtp-Source: ABdhPJx3rDhAxu96iOR8z7R+/QTTxHMH7vX+ldpFGCDtk0cYl3KpU5yM45A3IG5M1Gtt10S9XqrGcw== X-Received: by 2002:a17:90a:eb01:: with SMTP id j1mr6288651pjz.219.1610154152706; Fri, 08 Jan 2021 17:02:32 -0800 (PST) Received: from [2620:15c:17:3:4a0f:cfff:fe51:6667] ([2620:15c:17:3:4a0f:cfff:fe51:6667]) by smtp.gmail.com with ESMTPSA id 186sm10090171pfx.100.2021.01.08.17.02.31 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 08 Jan 2021 17:02:31 -0800 (PST) Date: Fri, 8 Jan 2021 17:02:30 -0800 (PST) From: David Rientjes To: Suren Baghdasaryan cc: Minchan Kim , Andrew Morton , Jann Horn , Kees Cook , Jeffrey Vander Stoep , Michal Hocko , Shakeel Butt , =?UTF-8?Q?Edgar_Arriaga_Garc=C3=ADa?= , Tim Murray , linux-mm , selinux@vger.kernel.org, Linux API , LKML , kernel-team Subject: Re: [PATCH 1/1] mm/madvise: replace ptrace attach requirement for process_madvise In-Reply-To: Message-ID: References: <20210108205857.1471269-1-surenb@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Precedence: bulk List-ID: X-Mailing-List: linux-api@vger.kernel.org On Fri, 8 Jan 2021, Suren Baghdasaryan wrote: > > > @@ -1197,12 +1197,22 @@ SYSCALL_DEFINE5(process_madvise, int, pidfd, const struct iovec __user *, vec, > > > goto release_task; > > > } > > > > > > - mm = mm_access(task, PTRACE_MODE_ATTACH_FSCREDS); > > > + /* Require PTRACE_MODE_READ to avoid leaking ASLR metadata. */ > > > + mm = mm_access(task, PTRACE_MODE_READ_FSCREDS); > > > if (IS_ERR_OR_NULL(mm)) { > > > ret = IS_ERR(mm) ? PTR_ERR(mm) : -ESRCH; > > > goto release_task; > > > } > > > > > > + /* > > > + * Require CAP_SYS_NICE for influencing process performance. Note that > > > + * only non-destructive hints are currently supported. > > > + */ > > > + if (!capable(CAP_SYS_NICE)) { > > > + ret = -EPERM; > > > + goto release_task; > > > > mmput? > > Ouch! Thanks for pointing it out! Will include in the next respin. > With the fix, feel free to add: Acked-by: David Rientjes Thanks Suren!