From patchwork Mon Jul 6 15:49:11 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christian Brauner X-Patchwork-Id: 11646095 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 82C65912 for ; Mon, 6 Jul 2020 15:51:41 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 5CA2320715 for ; Mon, 6 Jul 2020 15:51:41 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="JmD9GfZ4" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5CA2320715 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=ubuntu.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To:Message-Id:Date: Subject:To:From:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=DBRMrvV9N/m4npulionQWT1jpI3xK01shgt7Fiy2upg=; b=JmD9GfZ4DP3oO+eLEivGxuPcl nkoWrNimZj4C84VSdgi7lRFV/EjDzAEd/matY6wmmQp2CpxoiAyuV/Qrbi+bURFZbx6V2L3GNjKbk S/1fdMX6WZcWkZy4TrfEnNVUPWmKve1qbMfvDoNB9mHVcFpVF3X24gWKSlAZZqTjPFg8chy/1gtqn nbVn741TpciunRHjzUt/J/nBcxcnKeAKFzfNvaLN8S0BM2h+QT3+Lqb2uIuT1swpSoDAZQ1du+uvf 4HpOKV/nMNKA7e6Tl4LkwaBfIJu4cfv3IUNfy1J5gZD8Tbpjxx7iBhuspaMPbWXu3FfAA8Z9eUMYb zkDEQYH5Q==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jsTNG-00018Y-Bq; Mon, 06 Jul 2020 15:49:42 +0000 Received: from youngberry.canonical.com ([91.189.89.112]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1jsTMz-0000yo-29 for linux-arm-kernel@lists.infradead.org; Mon, 06 Jul 2020 15:49:26 +0000 Received: from ip5f5af08c.dynamic.kabel-deutschland.de ([95.90.240.140] helo=wittgenstein.fritz.box) by youngberry.canonical.com with esmtpsa (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.86_2) (envelope-from ) id 1jsTMv-0005O9-JL; Mon, 06 Jul 2020 15:49:21 +0000 From: Christian Brauner To: linux-kernel@vger.kernel.org Subject: [PATCH v2 3/4] nsproxy: support CLONE_NEWTIME with setns() Date: Mon, 6 Jul 2020 17:49:11 +0200 Message-Id: <20200706154912.3248030-4-christian.brauner@ubuntu.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200706154912.3248030-1-christian.brauner@ubuntu.com> References: <20200706154912.3248030-1-christian.brauner@ubuntu.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200706_114925_261888_29F1DB85 X-CRM114-Status: GOOD ( 14.40 ) X-Spam-Score: -1.4 (-) X-Spam-Report: SpamAssassin version 3.4.4 on merlin.infradead.org summary: Content analysis details: (-1.4 points) pts rule name description ---- ---------------------- -------------------------------------------------- 0.0 RCVD_IN_MSPIKE_H3 RBL: Good reputation (+3) [91.189.89.112 listed in wl.mailspike.net] 3.6 RCVD_IN_SBL_CSS RBL: Received via a relay in Spamhaus SBL-CSS [95.90.240.140 listed in zen.spamhaus.org] -5.0 RCVD_IN_DNSWL_HI RBL: Sender listed at https://www.dnswl.org/, high trust [91.189.89.112 listed in list.dnswl.org] 0.0 SPF_NONE SPF: sender does not publish an SPF Record 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record 0.0 RCVD_IN_MSPIKE_WL Mailspike good senders X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , Dmitry Safonov , Catalin Marinas , x86@kernel.org, Andrei Vagin , Michael Kerrisk , Andy Lutomirski , Thomas Gleixner , Vincenzo Frascino , Will Deacon , Christian Brauner , linux-arm-kernel@lists.infradead.org, Serge Hallyn Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org So far setns() was missing time namespace support. This was partially due to it simply not being implemented but also because vdso_join_timens() could still fail which made switching to multiple namespaces atomically problematic. This is now fixed so support CLONE_NEWTIME with setns() Signed-off-by: Christian Brauner Reviewed-by: Andrei Vagin Cc: Thomas Gleixner Cc: Michael Kerrisk Cc: Serge Hallyn Cc: Dmitry Safonov Link: https://lore.kernel.org/r/20200619153559.724863-4-christian.brauner@ubuntu.com --- include/linux/time_namespace.h | 6 ++++++ kernel/nsproxy.c | 21 +++++++++++++++++++-- kernel/time/namespace.c | 5 +---- 3 files changed, 26 insertions(+), 6 deletions(-) diff --git a/include/linux/time_namespace.h b/include/linux/time_namespace.h index 824d54e057eb..5b6031385db0 100644 --- a/include/linux/time_namespace.h +++ b/include/linux/time_namespace.h @@ -33,6 +33,7 @@ extern struct time_namespace init_time_ns; #ifdef CONFIG_TIME_NS extern int vdso_join_timens(struct task_struct *task, struct time_namespace *ns); +extern void timens_commit(struct task_struct *tsk, struct time_namespace *ns); static inline struct time_namespace *get_time_ns(struct time_namespace *ns) { @@ -96,6 +97,11 @@ static inline int vdso_join_timens(struct task_struct *task, return 0; } +static inline void timens_commit(struct task_struct *tsk, + struct time_namespace *ns) +{ +} + static inline struct time_namespace *get_time_ns(struct time_namespace *ns) { return NULL; diff --git a/kernel/nsproxy.c b/kernel/nsproxy.c index cd356630a311..12dd41b39a7f 100644 --- a/kernel/nsproxy.c +++ b/kernel/nsproxy.c @@ -262,8 +262,8 @@ void exit_task_namespaces(struct task_struct *p) static int check_setns_flags(unsigned long flags) { if (!flags || (flags & ~(CLONE_NEWNS | CLONE_NEWUTS | CLONE_NEWIPC | - CLONE_NEWNET | CLONE_NEWUSER | CLONE_NEWPID | - CLONE_NEWCGROUP))) + CLONE_NEWNET | CLONE_NEWTIME | CLONE_NEWUSER | + CLONE_NEWPID | CLONE_NEWCGROUP))) return -EINVAL; #ifndef CONFIG_USER_NS @@ -290,6 +290,10 @@ static int check_setns_flags(unsigned long flags) if (flags & CLONE_NEWNET) return -EINVAL; #endif +#ifndef CONFIG_TIME_NS + if (flags & CLONE_NEWTIME) + return -EINVAL; +#endif return 0; } @@ -464,6 +468,14 @@ static int validate_nsset(struct nsset *nsset, struct pid *pid) } #endif +#ifdef CONFIG_TIME_NS + if (flags & CLONE_NEWTIME) { + ret = validate_ns(nsset, &nsp->time_ns->ns); + if (ret) + goto out; + } +#endif + out: if (pid_ns) put_pid_ns(pid_ns); @@ -507,6 +519,11 @@ static void commit_nsset(struct nsset *nsset) exit_sem(me); #endif +#ifdef CONFIG_TIME_NS + if (flags & CLONE_NEWTIME) + timens_commit(me, nsset->nsproxy->time_ns); +#endif + /* transfer ownership */ switch_task_namespaces(me, nsset->nsproxy); nsset->nsproxy = NULL; diff --git a/kernel/time/namespace.c b/kernel/time/namespace.c index aa7b90aac2a7..afc65e6be33e 100644 --- a/kernel/time/namespace.c +++ b/kernel/time/namespace.c @@ -280,7 +280,7 @@ static void timens_put(struct ns_common *ns) put_time_ns(to_time_ns(ns)); } -static void timens_commit(struct task_struct *tsk, struct time_namespace *ns) +void timens_commit(struct task_struct *tsk, struct time_namespace *ns) { timens_set_vvar_page(tsk, ns); vdso_join_timens(tsk, ns); @@ -298,9 +298,6 @@ static int timens_install(struct nsset *nsset, struct ns_common *new) !ns_capable(nsset->cred->user_ns, CAP_SYS_ADMIN)) return -EPERM; - - timens_commit(current, ns); - get_time_ns(ns); put_time_ns(nsproxy->time_ns); nsproxy->time_ns = ns;