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 Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id D6759C433EF for ; Thu, 27 Jan 2022 14:34:13 +0000 (UTC) Received: from localhost ([::1]:37076 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1nD5qj-0002MC-8R for qemu-devel@archiver.kernel.org; Thu, 27 Jan 2022 09:34:09 -0500 Received: from eggs.gnu.org ([209.51.188.92]:52138) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nD5WE-0005FO-CI for qemu-devel@nongnu.org; Thu, 27 Jan 2022 09:12:59 -0500 Received: from mout.kundenserver.de ([212.227.17.10]:37565) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nD5WB-00021G-Ir for qemu-devel@nongnu.org; Thu, 27 Jan 2022 09:12:57 -0500 Received: from [192.168.100.1] ([82.142.25.174]) by mrelayeu.kundenserver.de (mreue108 [213.165.67.119]) with ESMTPSA (Nemesis) id 1MTzjI-1mmAxq36p8-00R3CE; Thu, 27 Jan 2022 15:12:52 +0100 Message-ID: Date: Thu, 27 Jan 2022 15:12:52 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.5.0 Subject: Re: [PATCH v3 1/2] linux-user: rt_sigprocmask, check read perms first Content-Language: fr To: Patrick Venture References: <20220126212559.1936290-1-venture@google.com> <20220126212559.1936290-2-venture@google.com> From: Laurent Vivier In-Reply-To: <20220126212559.1936290-2-venture@google.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Provags-ID: V03:K1:4nGB1caaMzBne3jJRrHqum10SiWV+7QApvt7EiH5n6eB7pZ9unf D2SspQhtNg/O4qEUBg9avGEVW8MyKtJgDnQp6f8xiOoZdQpXF3kPRQVHvp5itvw30e1UWTL iuCsAqsyRafubH2l9paApKHbKUcdbv/bdLe1LzSrMrG056UV69LoDp1XDBipWYnWEuUqKzr Qe8FaWF4DGvp4eoeReIlA== X-UI-Out-Filterresults: notjunk:1;V03:K0:ZjnSR9L4nhg=:UB9cqtKeYENoL0HHPCoE4i aaX/Bg9xD24GkdE6kpFUK2n8DjpSM7UwEjMvaY2W7gewnWEak2X7tqsoE+d2dDYFJW+cxGYoi 9PnC1Tqye/R6i1MC2RfDBXWY38PtdxIZJuSDOnUAkhmX7RWG1mlKMtAshDr/elOblKzjq4iTC NOx4Zmm83SoJShR5iv+X6TMjkaEd0sninTkJuHN+6ogdE6FNJHNwFdyh89tWxlh9qPf0OHQMF aEG0nuL8zj7VlqloT7Gmvz16DHsolnO+/6d+tm4x115HDVd3lVZM7u1XUjUmXGazIKKCh0yNv RG1yvj+TM5YOeUYIh44yr1J1/LV910DGdFDRFt1ogy3t65OyTtXrZAnNnUmvSLL4DigMmfMJM VibrWDxJBv7yYpDHOL9UzoPgCzeA36f1sAAQ8o+ihCVvy6rmQHjAOVtmVf9rXCaglihg/hGC6 y3Riv9lEk4S+PRb9rmtItqSePZIk2M2yQRYDiDiZ09vhGDYd2d6GNsE8nBTKQGfmWDAb/y7KS T0QbdwbHTCysftYbE7IW1thdbyOVVeaitx5yaQzRTnIOYGj6Thlm566NpCrAD7nKVuJryKJn0 85miirqCa5vJaNuakzPqcH7AAx2Z/R5/noGG2INdP6uF4r5LKPBRAVgfC82NXc2d1Zg2Jz0y6 UWOZVjYKqu8RmTOyyaNNp3T9fHAk7tWFjgJp6CuP8wyLwyKhhMw84CX9q5/VQO4wbhdo= Received-SPF: none client-ip=212.227.17.10; envelope-from=laurent@vivier.eu; helo=mout.kundenserver.de X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, NICE_REPLY_A=-0.001, RCVD_IN_MSPIKE_H2=-0.001, SPF_HELO_NONE=0.001, SPF_NONE=0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: qemu-devel@nongnu.org, scw@google.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Le 26/01/2022 à 22:25, Patrick Venture a écrit : > From: Shu-Chun Weng > > Linux kernel does it this way (checks read permission before validating `how`) > and the latest version of ABSL's `AddressIsReadable()` depends on this > behavior. > > c.f. https://github.com/torvalds/linux/blob/9539ba4308ad5bdca6cb41c7b73cbb9f796dcdd7/kernel/signal.c#L3147 > Reviewed-by: Patrick Venture > Signed-off-by: Shu-Chun Weng > Reviewed-by: Laurent Vivier > Signed-off-by: Patrick Venture > --- > linux-user/syscall.c | 12 +++++++----- > 1 file changed, 7 insertions(+), 5 deletions(-) > > diff --git a/linux-user/syscall.c b/linux-user/syscall.c > index 5950222a77..34bd819e38 100644 > --- a/linux-user/syscall.c > +++ b/linux-user/syscall.c > @@ -9508,6 +9508,13 @@ static abi_long do_syscall1(void *cpu_env, int num, abi_long arg1, > } > > if (arg2) { > + p = lock_user(VERIFY_READ, arg2, sizeof(target_sigset_t), 1); > + if (!p) { > + return -TARGET_EFAULT; > + } > + target_to_host_sigset(&set, p); > + unlock_user(p, arg2, 0); > + set_ptr = &set; > switch(how) { > case TARGET_SIG_BLOCK: > how = SIG_BLOCK; > @@ -9521,11 +9528,6 @@ static abi_long do_syscall1(void *cpu_env, int num, abi_long arg1, > default: > return -TARGET_EINVAL; > } > - if (!(p = lock_user(VERIFY_READ, arg2, sizeof(target_sigset_t), 1))) > - return -TARGET_EFAULT; > - target_to_host_sigset(&set, p); > - unlock_user(p, arg2, 0); > - set_ptr = &set; > } else { > how = 0; > set_ptr = NULL; Applied to my linux-user-for-7.0 branch. Thanks, Laurent