From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753183AbdHJMOc (ORCPT ); Thu, 10 Aug 2017 08:14:32 -0400 Received: from terminus.zytor.com ([65.50.211.136]:44659 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752366AbdHJMO3 (ORCPT ); Thu, 10 Aug 2017 08:14:29 -0400 Date: Thu, 10 Aug 2017 05:09:27 -0700 From: tip-bot for Aleksa Sarai Message-ID: Cc: torvalds@linux-foundation.org, linux-kernel@vger.kernel.org, asarai@suse.com, mingo@kernel.org, hpa@zytor.com, ebiederm@xmission.com, acidburn@google.com, peterz@infradead.org, tglx@linutronix.de Reply-To: ebiederm@xmission.com, acidburn@google.com, peterz@infradead.org, tglx@linutronix.de, torvalds@linux-foundation.org, linux-kernel@vger.kernel.org, asarai@suse.com, hpa@zytor.com, mingo@kernel.org In-Reply-To: <20170806044141.5093-1-asarai@suse.com> References: <20170806044141.5093-1-asarai@suse.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:sched/core] sched/debug: Use task_pid_nr_ns in /proc/$pid/sched Git-Commit-ID: 74dc3384fc7983b78cc46ebb1824968a3db85eb1 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: 74dc3384fc7983b78cc46ebb1824968a3db85eb1 Gitweb: http://git.kernel.org/tip/74dc3384fc7983b78cc46ebb1824968a3db85eb1 Author: Aleksa Sarai AuthorDate: Sun, 6 Aug 2017 14:41:41 +1000 Committer: Ingo Molnar CommitDate: Thu, 10 Aug 2017 12:18:19 +0200 sched/debug: Use task_pid_nr_ns in /proc/$pid/sched It appears as though the addition of the PID namespace did not update the output code for /proc/*/sched, which resulted in it providing PIDs that were not self-consistent with the /proc mount. This additionally made it trivial to detect whether a process was inside &init_pid_ns from userspace, making container detection trivial: https://github.com/jessfraz/amicontained This leads to situations such as: % unshare -pmf % mount -t proc proc /proc % head -n1 /proc/1/sched head (10047, #threads: 1) Fix this by just using task_pid_nr_ns for the output of /proc/*/sched. All of the other uses of task_pid_nr in kernel/sched/debug.c are from a sysctl context and thus don't need to be namespaced. Signed-off-by: Aleksa Sarai Signed-off-by: Peter Zijlstra (Intel) Acked-by: Eric W. Biederman Cc: Jess Frazelle Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: cyphar@cyphar.com Link: http://lkml.kernel.org/r/20170806044141.5093-1-asarai@suse.com Signed-off-by: Ingo Molnar --- fs/proc/base.c | 3 ++- include/linux/sched/debug.h | 4 +++- kernel/sched/debug.c | 5 +++-- 3 files changed, 8 insertions(+), 4 deletions(-) diff --git a/fs/proc/base.c b/fs/proc/base.c index 719c2e9..98fd8f6 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -1408,12 +1408,13 @@ static const struct file_operations proc_fail_nth_operations = { static int sched_show(struct seq_file *m, void *v) { struct inode *inode = m->private; + struct pid_namespace *ns = inode->i_sb->s_fs_info; struct task_struct *p; p = get_proc_task(inode); if (!p) return -ESRCH; - proc_sched_show_task(p, m); + proc_sched_show_task(p, ns, m); put_task_struct(p); diff --git a/include/linux/sched/debug.h b/include/linux/sched/debug.h index e0eaee5..5d58d49 100644 --- a/include/linux/sched/debug.h +++ b/include/linux/sched/debug.h @@ -6,6 +6,7 @@ */ struct task_struct; +struct pid_namespace; extern void dump_cpu_task(int cpu); @@ -34,7 +35,8 @@ extern void sched_show_task(struct task_struct *p); #ifdef CONFIG_SCHED_DEBUG struct seq_file; -extern void proc_sched_show_task(struct task_struct *p, struct seq_file *m); +extern void proc_sched_show_task(struct task_struct *p, + struct pid_namespace *ns, struct seq_file *m); extern void proc_sched_set_task(struct task_struct *p); #endif diff --git a/kernel/sched/debug.c b/kernel/sched/debug.c index 4fa66de..ac34511 100644 --- a/kernel/sched/debug.c +++ b/kernel/sched/debug.c @@ -872,11 +872,12 @@ static void sched_show_numa(struct task_struct *p, struct seq_file *m) #endif } -void proc_sched_show_task(struct task_struct *p, struct seq_file *m) +void proc_sched_show_task(struct task_struct *p, struct pid_namespace *ns, + struct seq_file *m) { unsigned long nr_switches; - SEQ_printf(m, "%s (%d, #threads: %d)\n", p->comm, task_pid_nr(p), + SEQ_printf(m, "%s (%d, #threads: %d)\n", p->comm, task_pid_nr_ns(p, ns), get_nr_threads(p)); SEQ_printf(m, "---------------------------------------------------------"