pid namespaces: changes to show virtual ids to user

This is the largest patch in the set. Make all (I hope) the places where
the pid is shown to or get from user operate on the virtual pids.

The idea is:
 - all in-kernel data structures must store either struct pid itself
   or the pid's global nr, obtained with pid_nr() call;
 - when seeking the task from kernel code with the stored id one
   should use find_task_by_pid() call that works with global pids;
 - when showing pid's numerical value to the user the virtual one
   should be used, but however when one shows task's pid outside this
   task's namespace the global one is to be used;
 - when getting the pid from userspace one need to consider this as
   the virtual one and use appropriate task/pid-searching functions.

[akpm@linux-foundation.org: build fix]
[akpm@linux-foundation.org: nuther build fix]
[akpm@linux-foundation.org: yet nuther build fix]
[akpm@linux-foundation.org: remove unneeded casts]
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: Alexey Dobriyan <adobriyan@openvz.org>
Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Paul Menage <menage@google.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/ia64/kernel/signal.c

@@ -227,7 +227,7 @@ ia64_rt_sigreturn (struct sigscratch *scr)
 	si.si_signo = SIGSEGV;
 	si.si_errno = 0;
 	si.si_code = SI_KERNEL;
-	si.si_pid = current->pid;
+	si.si_pid = task_pid_vnr(current);
 	si.si_uid = current->uid;
 	si.si_addr = sc;
 	force_sig_info(SIGSEGV, &si, current);
@@ -332,7 +332,7 @@ force_sigsegv_info (int sig, void __user *addr)
 	si.si_signo = SIGSEGV;
 	si.si_errno = 0;
 	si.si_code = SI_KERNEL;
-	si.si_pid = current->pid;
+	si.si_pid = task_pid_vnr(current);
 	si.si_uid = current->uid;
 	si.si_addr = addr;
 	force_sig_info(SIGSEGV, &si, current);

arch/parisc/kernel/signal.c

@@ -181,7 +181,7 @@ sys_rt_sigreturn(struct pt_regs *regs, int in_syscall)
 	si.si_signo = SIGSEGV;
 	si.si_errno = 0;
 	si.si_code = SI_KERNEL;
-	si.si_pid = current->pid;
+	si.si_pid = task_pid_vnr(current);
 	si.si_uid = current->uid;
 	si.si_addr = &frame->uc;
 	force_sig_info(SIGSEGV, &si, current);

arch/sparc/kernel/sys_sunos.c

@@ -866,7 +866,7 @@ asmlinkage int sunos_killpg(int pgrp, int sig)
 	rcu_read_lock();
 	ret = -EINVAL;
 	if (pgrp > 0)
-		ret = kill_pgrp(find_pid(pgrp), sig, 0);
+		ret = kill_pgrp(find_vpid(pgrp), sig, 0);
 	rcu_read_unlock();
 
 	return ret;

arch/sparc64/kernel/sys_sunos32.c

@@ -831,7 +831,7 @@ asmlinkage int sunos_killpg(int pgrp, int sig)
 	rcu_read_lock();
 	ret = -EINVAL;
 	if (pgrp > 0)
-		ret = kill_pgrp(find_pid(pgrp), sig, 0);
+		ret = kill_pgrp(find_vpid(pgrp), sig, 0);
 	rcu_read_unlock();
 
 	return ret;

drivers/char/tty_io.c

@@ -103,6 +103,7 @@
 #include <linux/selection.h>
 
 #include <linux/kmod.h>
+#include <linux/nsproxy.h>
 
 #undef TTY_DEBUG_HANGUP
 
@@ -3107,7 +3108,7 @@ static int tiocgpgrp(struct tty_struct *tty, struct tty_struct *real_tty, pid_t
 	 */
 	if (tty == real_tty && current->signal->tty != real_tty)
 		return -ENOTTY;
-	return put_user(pid_nr(real_tty->pgrp), p);
+	return put_user(pid_vnr(real_tty->pgrp), p);
 }
 
 /**
@@ -3141,7 +3142,7 @@ static int tiocspgrp(struct tty_struct *tty, struct tty_struct *real_tty, pid_t
 	if (pgrp_nr < 0)
 		return -EINVAL;
 	rcu_read_lock();
-	pgrp = find_pid(pgrp_nr);
+	pgrp = find_vpid(pgrp_nr);
 	retval = -ESRCH;
 	if (!pgrp)
 		goto out_unlock;
@@ -3178,7 +3179,7 @@ static int tiocgsid(struct tty_struct *tty, struct tty_struct *real_tty, pid_t _
 		return -ENOTTY;
 	if (!real_tty->session)
 		return -ENOTTY;
-	return put_user(pid_nr(real_tty->session), p);
+	return put_user(pid_vnr(real_tty->session), p);
 }
 
 /**

fs/binfmt_elf.c

@@ -1383,10 +1383,10 @@ static void fill_prstatus(struct elf_prstatus *prstatus,
 	prstatus->pr_info.si_signo = prstatus->pr_cursig = signr;
 	prstatus->pr_sigpend = p->pending.signal.sig[0];
 	prstatus->pr_sighold = p->blocked.sig[0];
-	prstatus->pr_pid = p->pid;
-	prstatus->pr_ppid = p->parent->pid;
-	prstatus->pr_pgrp = task_pgrp_nr(p);
-	prstatus->pr_sid = task_session_nr(p);
+	prstatus->pr_pid = task_pid_vnr(p);
+	prstatus->pr_ppid = task_pid_vnr(p->parent);
+	prstatus->pr_pgrp = task_pgrp_vnr(p);
+	prstatus->pr_sid = task_session_vnr(p);
 	if (thread_group_leader(p)) {
 		/*
 		 * This is the record for the group leader.  Add in the
@@ -1429,10 +1429,10 @@ static int fill_psinfo(struct elf_prpsinfo *psinfo, struct task_struct *p,
 			psinfo->pr_psargs[i] = ' ';
 	psinfo->pr_psargs[len] = 0;
 
-	psinfo->pr_pid = p->pid;
-	psinfo->pr_ppid = p->parent->pid;
-	psinfo->pr_pgrp = task_pgrp_nr(p);
-	psinfo->pr_sid = task_session_nr(p);
+	psinfo->pr_pid = task_pid_vnr(p);
+	psinfo->pr_ppid = task_pid_vnr(p->parent);
+	psinfo->pr_pgrp = task_pgrp_vnr(p);
+	psinfo->pr_sid = task_session_vnr(p);
 
 	i = p->state ? ffz(~p->state) + 1 : 0;
 	psinfo->pr_state = i;

fs/binfmt_elf_fdpic.c

@@ -1342,10 +1342,10 @@ static void fill_prstatus(struct elf_prstatus *prstatus,
 	prstatus->pr_info.si_signo = prstatus->pr_cursig = signr;
 	prstatus->pr_sigpend = p->pending.signal.sig[0];
 	prstatus->pr_sighold = p->blocked.sig[0];
-	prstatus->pr_pid = p->pid;
-	prstatus->pr_ppid = p->parent->pid;
-	prstatus->pr_pgrp = task_pgrp_nr(p);
-	prstatus->pr_sid = task_session_nr(p);
+	prstatus->pr_pid = task_pid_vnr(p);
+	prstatus->pr_ppid = task_pid_vnr(p->parent);
+	prstatus->pr_pgrp = task_pgrp_vnr(p);
+	prstatus->pr_sid = task_session_vnr(p);
 	if (thread_group_leader(p)) {
 		/*
 		 * This is the record for the group leader.  Add in the
@@ -1391,10 +1391,10 @@ static int fill_psinfo(struct elf_prpsinfo *psinfo, struct task_struct *p,
 			psinfo->pr_psargs[i] = ' ';
 	psinfo->pr_psargs[len] = 0;
 
-	psinfo->pr_pid = p->pid;
-	psinfo->pr_ppid = p->parent->pid;
-	psinfo->pr_pgrp = task_pgrp_nr(p);
-	psinfo->pr_sid = task_session_nr(p);
+	psinfo->pr_pid = task_pid_vnr(p);
+	psinfo->pr_ppid = task_pid_vnr(p->parent);
+	psinfo->pr_pgrp = task_pgrp_vnr(p);
+	psinfo->pr_sid = task_session_vnr(p);
 
 	i = p->state ? ffz(~p->state) + 1 : 0;
 	psinfo->pr_state = i;

fs/exec.c

@@ -1433,7 +1433,7 @@ static int format_corename(char *corename, const char *pattern, long signr)
 			case 'p':
 				pid_in_pattern = 1;
 				rc = snprintf(out_ptr, out_end - out_ptr,
-					      "%d", current->tgid);
+					      "%d", task_tgid_vnr(current));
 				if (rc > out_end - out_ptr)
 					goto out;
 				out_ptr += rc;
@@ -1513,7 +1513,7 @@ static int format_corename(char *corename, const char *pattern, long signr)
 	if (!ispipe && !pid_in_pattern
             && (core_uses_pid || atomic_read(&current->mm->mm_users) != 1)) {
 		rc = snprintf(out_ptr, out_end - out_ptr,
-			      ".%d", current->tgid);
+			      ".%d", task_tgid_vnr(current));
 		if (rc > out_end - out_ptr)
 			goto out;
 		out_ptr += rc;

fs/fcntl.c

@@ -18,6 +18,7 @@
 #include <linux/ptrace.h>
 #include <linux/signal.h>
 #include <linux/rcupdate.h>
+#include <linux/pid_namespace.h>
 
 #include <asm/poll.h>
 #include <asm/siginfo.h>
@@ -292,7 +293,7 @@ int f_setown(struct file *filp, unsigned long arg, int force)
 		who = -who;
 	}
 	rcu_read_lock();
-	pid = find_pid(who);
+	pid = find_vpid(who);
 	result = __f_setown(filp, pid, type, force);
 	rcu_read_unlock();
 	return result;
@@ -308,7 +309,7 @@ pid_t f_getown(struct file *filp)
 {
 	pid_t pid;
 	read_lock(&filp->f_owner.lock);
-	pid = pid_nr(filp->f_owner.pid);
+	pid = pid_nr_ns(filp->f_owner.pid, current->nsproxy->pid_ns);
 	if (filp->f_owner.pid_type == PIDTYPE_PGID)
 		pid = -pid;
 	read_unlock(&filp->f_owner.lock);

fs/ioprio.c

@@ -25,6 +25,7 @@
 #include <linux/capability.h>
 #include <linux/syscalls.h>
 #include <linux/security.h>
+#include <linux/pid_namespace.h>
 
 static int set_task_ioprio(struct task_struct *task, int ioprio)
 {
@@ -93,7 +94,8 @@ asmlinkage long sys_ioprio_set(int which, int who, int ioprio)
 			if (!who)
 				p = current;
 			else
-				p = find_task_by_pid(who);
+				p = find_task_by_pid_ns(who,
+						current->nsproxy->pid_ns);
 			if (p)
 				ret = set_task_ioprio(p, ioprio);
 			break;
@@ -101,7 +103,7 @@ asmlinkage long sys_ioprio_set(int which, int who, int ioprio)
 			if (!who)
 				pgrp = task_pgrp(current);
 			else
-				pgrp = find_pid(who);
+				pgrp = find_vpid(who);
 			do_each_pid_task(pgrp, PIDTYPE_PGID, p) {
 				ret = set_task_ioprio(p, ioprio);
 				if (ret)
@@ -180,7 +182,8 @@ asmlinkage long sys_ioprio_get(int which, int who)
 			if (!who)
 				p = current;
 			else
-				p = find_task_by_pid(who);
+				p = find_task_by_pid_ns(who,
+						current->nsproxy->pid_ns);
 			if (p)
 				ret = get_task_ioprio(p);
 			break;
@@ -188,7 +191,7 @@ asmlinkage long sys_ioprio_get(int which, int who)
 			if (!who)
 				pgrp = task_pgrp(current);
 			else
-				pgrp = find_pid(who);
+				pgrp = find_vpid(who);
 			do_each_pid_task(pgrp, PIDTYPE_PGID, p) {
 				tmpio = get_task_ioprio(p);
 				if (tmpio < 0)

fs/proc/array.c

@@ -77,6 +77,7 @@
 #include <linux/cpuset.h>
 #include <linux/rcupdate.h>
 #include <linux/delayacct.h>
+#include <linux/pid_namespace.h>
 
 #include <asm/pgtable.h>
 #include <asm/processor.h>
@@ -161,8 +162,15 @@ static inline char *task_state(struct task_struct *p, char *buffer)
 	struct group_info *group_info;
 	int g;
 	struct fdtable *fdt = NULL;
+	struct pid_namespace *ns;
+	pid_t ppid, tpid;
 
+	ns = current->nsproxy->pid_ns;
 	rcu_read_lock();
+	ppid = pid_alive(p) ?
+		task_tgid_nr_ns(rcu_dereference(p->real_parent), ns) : 0;
+	tpid = pid_alive(p) && p->ptrace ?
+		task_ppid_nr_ns(rcu_dereference(p->parent), ns) : 0;
 	buffer += sprintf(buffer,
 		"State:\t%s\n"
 		"Tgid:\t%d\n"
@@ -172,9 +180,9 @@ static inline char *task_state(struct task_struct *p, char *buffer)
 		"Uid:\t%d\t%d\t%d\t%d\n"
 		"Gid:\t%d\t%d\t%d\t%d\n",
 		get_task_state(p),
-		p->tgid, p->pid,
-		pid_alive(p) ? rcu_dereference(p->real_parent)->tgid : 0,
-		pid_alive(p) && p->ptrace ? rcu_dereference(p->parent)->pid : 0,
+		task_tgid_nr_ns(p, ns),
+		task_pid_nr_ns(p, ns),
+		ppid, tpid,
 		p->uid, p->euid, p->suid, p->fsuid,
 		p->gid, p->egid, p->sgid, p->fsgid);
 
@@ -394,6 +402,9 @@ static int do_task_stat(struct task_struct *task, char *buffer, int whole)
 	unsigned long rsslim = 0;
 	char tcomm[sizeof(task->comm)];
 	unsigned long flags;
+	struct pid_namespace *ns;
+
+	ns = current->nsproxy->pid_ns;
 
 	state = *get_task_state(task);
 	vsize = eip = esp = 0;
@@ -416,7 +427,7 @@ static int do_task_stat(struct task_struct *task, char *buffer, int whole)
 		struct signal_struct *sig = task->signal;
 
 		if (sig->tty) {
-			tty_pgrp = pid_nr(sig->tty->pgrp);
+			tty_pgrp = pid_nr_ns(sig->tty->pgrp, ns);
 			tty_nr = new_encode_dev(tty_devnum(sig->tty));
 		}
 
@@ -449,9 +460,9 @@ static int do_task_stat(struct task_struct *task, char *buffer, int whole)
 			gtime += cputime_add(gtime, sig->gtime);
 		}
 
-		sid = task_session_nr(task);
-		pgid = task_pgrp_nr(task);
-		ppid = rcu_dereference(task->real_parent)->tgid;
+		sid = task_session_nr_ns(task, ns);
+		pgid = task_pgrp_nr_ns(task, ns);
+		ppid = task_ppid_nr_ns(task, ns);
 
 		unlock_task_sighand(task, &flags);
 	}
@@ -483,7 +494,7 @@ static int do_task_stat(struct task_struct *task, char *buffer, int whole)
 	res = sprintf(buffer, "%d (%s) %c %d %d %d %d %d %u %lu \
 %lu %lu %lu %lu %lu %ld %ld %ld %ld %d 0 %llu %lu %ld %lu %lu %lu %lu %lu \
 %lu %lu %lu %lu %lu %lu %lu %lu %d %d %u %u %llu %lu %ld\n",
-		task->pid,
+		task_pid_nr_ns(task, ns),
 		tcomm,
 		state,
 		ppid,

fs/proc/base.c

@@ -1937,14 +1937,14 @@ static int proc_self_readlink(struct dentry *dentry, char __user *buffer,
 			      int buflen)
 {
 	char tmp[PROC_NUMBUF];
-	sprintf(tmp, "%d", current->tgid);
+	sprintf(tmp, "%d", task_tgid_vnr(current));
 	return vfs_readlink(dentry,buffer,buflen,tmp);
 }
 
 static void *proc_self_follow_link(struct dentry *dentry, struct nameidata *nd)
 {
 	char tmp[PROC_NUMBUF];
-	sprintf(tmp, "%d", current->tgid);
+	sprintf(tmp, "%d", task_tgid_vnr(current));
 	return ERR_PTR(vfs_follow_link(nd,tmp));
 }
 
@@ -2316,6 +2316,7 @@ struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, struct
 	struct dentry *result = ERR_PTR(-ENOENT);
 	struct task_struct *task;
 	unsigned tgid;
+	struct pid_namespace *ns;
 
 	result = proc_base_lookup(dir, dentry);
 	if (!IS_ERR(result) || PTR_ERR(result) != -ENOENT)
@@ -2325,8 +2326,9 @@ struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, struct
 	if (tgid == ~0U)
 		goto out;
 
+	ns = dentry->d_sb->s_fs_info;
 	rcu_read_lock();
-	task = find_task_by_pid(tgid);
+	task = find_task_by_pid_ns(tgid, ns);
 	if (task)
 		get_task_struct(task);
 	rcu_read_unlock();
@@ -2343,7 +2345,8 @@ struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, struct
  * Find the first task with tgid >= tgid
  *
  */
-static struct task_struct *next_tgid(unsigned int tgid)
+static struct task_struct *next_tgid(unsigned int tgid,
+		struct pid_namespace *ns)
 {
 	struct task_struct *task;
 	struct pid *pid;
@@ -2351,9 +2354,9 @@ static struct task_struct *next_tgid(unsigned int tgid)
 	rcu_read_lock();
 retry:
 	task = NULL;
-	pid = find_ge_pid(tgid, &init_pid_ns);
+	pid = find_ge_pid(tgid, ns);
 	if (pid) {
-		tgid = pid->nr + 1;
+		tgid = pid_nr_ns(pid, ns) + 1;
 		task = pid_task(pid, PIDTYPE_PID);
 		/* What we to know is if the pid we have find is the
 		 * pid of a thread_group_leader.  Testing for task
@@ -2393,6 +2396,7 @@ int proc_pid_readdir(struct file * filp, void * dirent, filldir_t filldir)
 	struct task_struct *reaper = get_proc_task(filp->f_path.dentry->d_inode);
 	struct task_struct *task;
 	int tgid;
+	struct pid_namespace *ns;
 
 	if (!reaper)
 		goto out_no_task;
@@ -2403,11 +2407,12 @@ int proc_pid_readdir(struct file * filp, void * dirent, filldir_t filldir)
 			goto out;
 	}
 
+	ns = filp->f_dentry->d_sb->s_fs_info;
 	tgid = filp->f_pos - TGID_OFFSET;
-	for (task = next_tgid(tgid);
+	for (task = next_tgid(tgid, ns);
 	     task;
-	     put_task_struct(task), task = next_tgid(tgid + 1)) {
-		tgid = task->pid;
+	     put_task_struct(task), task = next_tgid(tgid + 1, ns)) {
+		tgid = task_pid_nr_ns(task, ns);
 		filp->f_pos = tgid + TGID_OFFSET;
 		if (proc_pid_fill_cache(filp, dirent, filldir, task, tgid) < 0) {
 			put_task_struct(task);
@@ -2531,6 +2536,7 @@ static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry
 	struct task_struct *task;
 	struct task_struct *leader = get_proc_task(dir);
 	unsigned tid;
+	struct pid_namespace *ns;
 
 	if (!leader)
 		goto out_no_task;
@@ -2539,8 +2545,9 @@ static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry
 	if (tid == ~0U)
 		goto out;
 
+	ns = dentry->d_sb->s_fs_info;
 	rcu_read_lock();
-	task = find_task_by_pid(tid);
+	task = find_task_by_pid_ns(tid, ns);
 	if (task)
 		get_task_struct(task);
 	rcu_read_unlock();
@@ -2571,14 +2578,14 @@ static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry
  * threads past it.
  */
 static struct task_struct *first_tid(struct task_struct *leader,
-					int tid, int nr)
+		int tid, int nr, struct pid_namespace *ns)
 {
 	struct task_struct *pos;
 
 	rcu_read_lock();
 	/* Attempt to start with the pid of a thread */
 	if (tid && (nr > 0)) {
-		pos = find_task_by_pid(tid);
+		pos = find_task_by_pid_ns(tid, ns);
 		if (pos && (pos->group_leader == leader))
 			goto found;
 	}
@@ -2647,6 +2654,7 @@ static int proc_task_readdir(struct file * filp, void * dirent, filldir_t filldi
 	ino_t ino;
 	int tid;
 	unsigned long pos = filp->f_pos;  /* avoiding "long long" filp->f_pos */
+	struct pid_namespace *ns;
 
 	task = get_proc_task(inode);
 	if (!task)
@@ -2680,12 +2688,13 @@ static int proc_task_readdir(struct file * filp, void * dirent, filldir_t filldi
 	/* f_version caches the tgid value that the last readdir call couldn't
 	 * return. lseek aka telldir automagically resets f_version to 0.
 	 */
+	ns = filp->f_dentry->d_sb->s_fs_info;
 	tid = (int)filp->f_version;
 	filp->f_version = 0;
-	for (task = first_tid(leader, tid, pos - 2);
+	for (task = first_tid(leader, tid, pos - 2, ns);
 	     task;
 	     task = next_tid(task), pos++) {
-		tid = task->pid;
+		tid = task_pid_nr_ns(task, ns);
 		if (proc_task_fill_cache(filp, dirent, filldir, task, tid) < 0) {
 			/* returning this tgid failed, save it as the first
 			 * pid for the next readir call */

include/net/scm.h

@@ -4,6 +4,8 @@
 #include <linux/limits.h>
 #include <linux/net.h>
 #include <linux/security.h>
+#include <linux/pid.h>
+#include <linux/nsproxy.h>
 
 /* Well, we should have at least one descriptor open
  * to accept passed FDs 8)
@@ -54,7 +56,7 @@ static __inline__ int scm_send(struct socket *sock, struct msghdr *msg,
 	struct task_struct *p = current;
 	scm->creds.uid = p->uid;
 	scm->creds.gid = p->gid;
-	scm->creds.pid = p->tgid;
+	scm->creds.pid = task_tgid_vnr(p);
 	scm->fp = NULL;
 	scm->seq = 0;
 	unix_get_peersec_dgram(sock, scm);

ipc/mqueue.c

@@ -29,6 +29,8 @@
 #include <linux/audit.h>
 #include <linux/signal.h>
 #include <linux/mutex.h>
+#include <linux/nsproxy.h>
+#include <linux/pid.h>
 
 #include <net/sock.h>
 #include "util.h"
@@ -330,7 +332,8 @@ static ssize_t mqueue_read_file(struct file *filp, char __user *u_data,
 			(info->notify_owner &&
 			 info->notify.sigev_notify == SIGEV_SIGNAL) ?
 				info->notify.sigev_signo : 0,
-			pid_nr(info->notify_owner));
+			pid_nr_ns(info->notify_owner,
+				current->nsproxy->pid_ns));
 	spin_unlock(&info->lock);
 	buffer[sizeof(buffer)-1] = '\0';
 	slen = strlen(buffer)+1;
@@ -507,7 +510,7 @@ static void __do_notify(struct mqueue_inode_info *info)
 			sig_i.si_errno = 0;
 			sig_i.si_code = SI_MESGQ;
 			sig_i.si_value = info->notify.sigev_value;
-			sig_i.si_pid = current->tgid;
+			sig_i.si_pid = task_pid_vnr(current);
 			sig_i.si_uid = current->uid;
 
 			kill_pid_info(info->notify.sigev_signo,

ipc/msg.c

@@ -611,7 +611,7 @@ static inline int pipelined_send(struct msg_queue *msq, struct msg_msg *msg)
 				msr->r_msg = ERR_PTR(-E2BIG);
 			} else {
 				msr->r_msg = NULL;
-				msq->q_lrpid = msr->r_tsk->pid;
+				msq->q_lrpid = task_pid_vnr(msr->r_tsk);
 				msq->q_rtime = get_seconds();
 				wake_up_process(msr->r_tsk);
 				smp_mb();
@@ -695,7 +695,7 @@ long do_msgsnd(int msqid, long mtype, void __user *mtext,
 		}
 	}
 
-	msq->q_lspid = current->tgid;
+	msq->q_lspid = task_tgid_vnr(current);
 	msq->q_stime = get_seconds();
 
 	if (!pipelined_send(msq, msg)) {
@@ -810,7 +810,7 @@ long do_msgrcv(int msqid, long *pmtype, void __user *mtext,
 			list_del(&msg->m_list);
 			msq->q_qnum--;
 			msq->q_rtime = get_seconds();
-			msq->q_lrpid = current->tgid;
+			msq->q_lrpid = task_tgid_vnr(current);
 			msq->q_cbytes -= msg->m_ts;
 			atomic_sub(msg->m_ts, &msg_bytes);
 			atomic_dec(&msg_hdrs);

ipc/sem.c

@@ -795,7 +795,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum,
 		for (un = sma->undo; un; un = un->id_next)
 			un->semadj[semnum] = 0;
 		curr->semval = val;
-		curr->sempid = current->tgid;
+		curr->sempid = task_tgid_vnr(current);
 		sma->sem_ctime = get_seconds();
 		/* maybe some queued-up processes were waiting for this */
 		update_queue(sma);
@@ -1196,7 +1196,7 @@ asmlinkage long sys_semtimedop(int semid, struct sembuf __user *tsops,
 	if (error)
 		goto out_unlock_free;
 
-	error = try_atomic_semop (sma, sops, nsops, un, current->tgid);
+	error = try_atomic_semop (sma, sops, nsops, un, task_tgid_vnr(current));
 	if (error <= 0) {
 		if (alter && error == 0)
 			update_queue (sma);
@@ -1211,7 +1211,7 @@ asmlinkage long sys_semtimedop(int semid, struct sembuf __user *tsops,
 	queue.sops = sops;
 	queue.nsops = nsops;
 	queue.undo = un;
-	queue.pid = current->tgid;
+	queue.pid = task_tgid_vnr(current);
 	queue.id = semid;
 	queue.alter = alter;
 	if (alter)
@@ -1382,7 +1382,7 @@ void exit_sem(struct task_struct *tsk)
 					semaphore->semval = 0;
 				if (semaphore->semval > SEMVMX)
 					semaphore->semval = SEMVMX;
-				semaphore->sempid = current->tgid;
+				semaphore->sempid = task_tgid_vnr(current);
 			}
 		}
 		sma->sem_otime = get_seconds();

ipc/shm.c

@@ -168,7 +168,7 @@ static void shm_open(struct vm_area_struct *vma)
 	shp = shm_lock(sfd->ns, sfd->id);
 	BUG_ON(!shp);
 	shp->shm_atim = get_seconds();
-	shp->shm_lprid = current->tgid;
+	shp->shm_lprid = task_tgid_vnr(current);
 	shp->shm_nattch++;
 	shm_unlock(shp);
 }
@@ -213,7 +213,7 @@ static void shm_close(struct vm_area_struct *vma)
 	/* remove from the list of attaches of the shm segment */
 	shp = shm_lock(ns, sfd->id);
 	BUG_ON(!shp);
-	shp->shm_lprid = current->tgid;
+	shp->shm_lprid = task_tgid_vnr(current);
 	shp->shm_dtim = get_seconds();
 	shp->shm_nattch--;
 	if(shp->shm_nattch == 0 &&
@@ -392,7 +392,7 @@ static int newseg (struct ipc_namespace *ns, key_t key, int shmflg, size_t size)
 	if(id == -1) 
 		goto no_id;
 
-	shp->shm_cprid = current->tgid;
+	shp->shm_cprid = task_tgid_vnr(current);
 	shp->shm_lprid = 0;
 	shp->shm_atim = shp->shm_dtim = 0;
 	shp->shm_ctim = get_seconds();

kernel/capability.c

@@ -62,8 +62,9 @@ asmlinkage long sys_capget(cap_user_header_t header, cap_user_data_t dataptr)
 	spin_lock(&task_capability_lock);
 	read_lock(&tasklist_lock);
 
-	if (pid && pid != current->pid) {
-		target = find_task_by_pid(pid);
+	if (pid && pid != task_pid_vnr(current)) {
+		target = find_task_by_pid_ns(pid,
+				current->nsproxy->pid_ns);
 		if (!target) {
 			ret = -ESRCH;
 			goto out;
@@ -96,7 +97,7 @@ static inline int cap_set_pg(int pgrp_nr, kernel_cap_t *effective,
 	int found = 0;
 	struct pid *pgrp;
 
-	pgrp = find_pid(pgrp_nr);
+	pgrp = find_pid_ns(pgrp_nr, current->nsproxy->pid_ns);
 	do_each_pid_task(pgrp, PIDTYPE_PGID, g) {
 		target = g;
 		while_each_thread(g, target) {
@@ -185,7 +186,7 @@ asmlinkage long sys_capset(cap_user_header_t header, const cap_user_data_t data)
 	if (get_user(pid, &header->pid))
 		return -EFAULT;
 
-	if (pid && pid != current->pid && !capable(CAP_SETPCAP))
+	if (pid && pid != task_pid_vnr(current) && !capable(CAP_SETPCAP))
 		return -EPERM;
 
 	if (copy_from_user(&effective, &data->effective, sizeof(effective)) ||
@@ -196,8 +197,9 @@ asmlinkage long sys_capset(cap_user_header_t header, const cap_user_data_t data)
 	spin_lock(&task_capability_lock);
 	read_lock(&tasklist_lock);
 
-	if (pid > 0 && pid != current->pid) {
-		target = find_task_by_pid(pid);
+	if (pid > 0 && pid != task_pid_vnr(current)) {
+		target = find_task_by_pid_ns(pid,
+				current->nsproxy->pid_ns);
 		if (!target) {
 			ret = -ESRCH;
 			goto out;

kernel/exit.c

@@ -1112,15 +1112,17 @@ asmlinkage void sys_exit_group(int error_code)
 static int eligible_child(pid_t pid, int options, struct task_struct *p)
 {
 	int err;
+	struct pid_namespace *ns;
 
+	ns = current->nsproxy->pid_ns;
 	if (pid > 0) {
-		if (p->pid != pid)
+		if (task_pid_nr_ns(p, ns) != pid)
 			return 0;
 	} else if (!pid) {
-		if (task_pgrp_nr(p) != task_pgrp_nr(current))
+		if (task_pgrp_nr_ns(p, ns) != task_pgrp_vnr(current))
 			return 0;
 	} else if (pid != -1) {
-		if (task_pgrp_nr(p) != -pid)
+		if (task_pgrp_nr_ns(p, ns) != -pid)
 			return 0;
 	}
 
@@ -1190,9 +1192,12 @@ static int wait_task_zombie(struct task_struct *p, int noreap,
 {
 	unsigned long state;
 	int retval, status, traced;
+	struct pid_namespace *ns;
+
+	ns = current->nsproxy->pid_ns;
 
 	if (unlikely(noreap)) {
-		pid_t pid = p->pid;
+		pid_t pid = task_pid_nr_ns(p, ns);
 		uid_t uid = p->uid;
 		int exit_code = p->exit_code;
 		int why, status;
@@ -1311,11 +1316,11 @@ static int wait_task_zombie(struct task_struct *p, int noreap,
 			retval = put_user(status, &infop->si_status);
 	}
 	if (!retval && infop)
-		retval = put_user(p->pid, &infop->si_pid);
+		retval = put_user(task_pid_nr_ns(p, ns), &infop->si_pid);
 	if (!retval && infop)
 		retval = put_user(p->uid, &infop->si_uid);
 	if (!retval)
-		retval = p->pid;
+		retval = task_pid_nr_ns(p, ns);
 
 	if (traced) {
 		write_lock_irq(&tasklist_lock);
@@ -1352,6 +1357,7 @@ static int wait_task_stopped(struct task_struct *p, int delayed_group_leader,
 			     int __user *stat_addr, struct rusage __user *ru)
 {
 	int retval, exit_code;
+	struct pid_namespace *ns;
 
 	if (!p->exit_code)
 		return 0;
@@ -1370,11 +1376,12 @@ static int wait_task_stopped(struct task_struct *p, int delayed_group_leader,
 	 * keep holding onto the tasklist_lock while we call getrusage and
 	 * possibly take page faults for user memory.
 	 */
+	ns = current->nsproxy->pid_ns;
 	get_task_struct(p);
 	read_unlock(&tasklist_lock);
 
 	if (unlikely(noreap)) {
-		pid_t pid = p->pid;
+		pid_t pid = task_pid_nr_ns(p, ns);
 		uid_t uid = p->uid;
 		int why = (p->ptrace & PT_PTRACED) ? CLD_TRAPPED : CLD_STOPPED;
 
@@ -1445,11 +1452,11 @@ static int wait_task_stopped(struct task_struct *p, int delayed_group_leader,
 	if (!retval && infop)
 		retval = put_user(exit_code, &infop->si_status);
 	if (!retval && infop)
-		retval = put_user(p->pid, &infop->si_pid);
+		retval = put_user(task_pid_nr_ns(p, ns), &infop->si_pid);
 	if (!retval && infop)
 		retval = put_user(p->uid, &infop->si_uid);
 	if (!retval)
-		retval = p->pid;
+		retval = task_pid_nr_ns(p, ns);
 	put_task_struct(p);
 
 	BUG_ON(!retval);
@@ -1469,6 +1476,7 @@ static int wait_task_continued(struct task_struct *p, int noreap,
 	int retval;
 	pid_t pid;
 	uid_t uid;
+	struct pid_namespace *ns;
 
 	if (!(p->signal->flags & SIGNAL_STOP_CONTINUED))
 		return 0;
@@ -1483,7 +1491,8 @@ static int wait_task_continued(struct task_struct *p, int noreap,
 		p->signal->flags &= ~SIGNAL_STOP_CONTINUED;
 	spin_unlock_irq(&p->sighand->siglock);
 
-	pid = p->pid;
+	ns = current->nsproxy->pid_ns;
+	pid = task_pid_nr_ns(p, ns);
 	uid = p->uid;
 	get_task_struct(p);
 	read_unlock(&tasklist_lock);
@@ -1494,7 +1503,7 @@ static int wait_task_continued(struct task_struct *p, int noreap,
 		if (!retval && stat_addr)
 			retval = put_user(0xffff, stat_addr);
 		if (!retval)
-			retval = p->pid;
+			retval = task_pid_nr_ns(p, ns);
 	} else {
 		retval = wait_noreap_copyout(p, pid, uid,
 					     CLD_CONTINUED, SIGCONT,

kernel/fork.c

@@ -950,7 +950,7 @@ asmlinkage long sys_set_tid_address(int __user *tidptr)
 {
 	current->clear_child_tid = tidptr;
 
-	return current->pid;
+	return task_pid_vnr(current);
 }
 
 static inline void rt_mutex_init_task(struct task_struct *p)

kernel/futex.c

@@ -53,6 +53,9 @@
 #include <linux/signal.h>
 #include <linux/module.h>
 #include <linux/magic.h>
+#include <linux/pid.h>
+#include <linux/nsproxy.h>
+
 #include <asm/futex.h>
 
 #include "rtmutex_common.h"
@@ -443,7 +446,8 @@ static struct task_struct * futex_find_get_task(pid_t pid)
 	struct task_struct *p;
 
 	rcu_read_lock();
-	p = find_task_by_pid(pid);
+	p = find_task_by_pid_ns(pid,
+			current->nsproxy->pid_ns);
 
 	if (!p || ((current->euid != p->euid) && (current->euid != p->uid)))
 		p = ERR_PTR(-ESRCH);
@@ -653,7 +657,7 @@ static int wake_futex_pi(u32 __user *uaddr, u32 uval, struct futex_q *this)
 	if (!(uval & FUTEX_OWNER_DIED)) {
 		int ret = 0;
 
-		newval = FUTEX_WAITERS | new_owner->pid;
+		newval = FUTEX_WAITERS | task_pid_vnr(new_owner);
 
 		curval = cmpxchg_futex_value_locked(uaddr, uval, newval);
 
@@ -1106,7 +1110,7 @@ static void unqueue_me_pi(struct futex_q *q)
 static int fixup_pi_state_owner(u32 __user *uaddr, struct futex_q *q,
 				struct task_struct *curr)
 {
-	u32 newtid = curr->pid | FUTEX_WAITERS;
+	u32 newtid = task_pid_vnr(curr) | FUTEX_WAITERS;
 	struct futex_pi_state *pi_state = q->pi_state;
 	u32 uval, curval, newval;
 	int ret;
@@ -1368,7 +1372,7 @@ static int futex_lock_pi(u32 __user *uaddr, struct rw_semaphore *fshared,
 	 * (by doing a 0 -> TID atomic cmpxchg), while holding all
 	 * the locks. It will most likely not succeed.
 	 */
-	newval = current->pid;
+	newval = task_pid_vnr(current);
 
 	curval = cmpxchg_futex_value_locked(uaddr, 0, newval);
 
@@ -1379,7 +1383,7 @@ static int futex_lock_pi(u32 __user *uaddr, struct rw_semaphore *fshared,
 	 * Detect deadlocks. In case of REQUEUE_PI this is a valid
 	 * situation and we return success to user space.
 	 */
-	if (unlikely((curval & FUTEX_TID_MASK) == current->pid)) {
+	if (unlikely((curval & FUTEX_TID_MASK) == task_pid_vnr(current))) {
 		ret = -EDEADLK;
 		goto out_unlock_release_sem;
 	}
@@ -1408,7 +1412,7 @@ static int futex_lock_pi(u32 __user *uaddr, struct rw_semaphore *fshared,
 	 */
 	if (unlikely(ownerdied || !(curval & FUTEX_TID_MASK))) {
 		/* Keep the OWNER_DIED bit */
-		newval = (curval & ~FUTEX_TID_MASK) | current->pid;
+		newval = (curval & ~FUTEX_TID_MASK) | task_pid_vnr(current);
 		ownerdied = 0;
 		lock_taken = 1;
 	}
@@ -1587,7 +1591,7 @@ static int futex_unlock_pi(u32 __user *uaddr, struct rw_semaphore *fshared)
 	/*
 	 * We release only a lock we actually own:
 	 */
-	if ((uval & FUTEX_TID_MASK) != current->pid)
+	if ((uval & FUTEX_TID_MASK) != task_pid_vnr(current))
 		return -EPERM;
 	/*
 	 * First take all the futex related locks:
@@ -1608,7 +1612,7 @@ static int futex_unlock_pi(u32 __user *uaddr, struct rw_semaphore *fshared)
 	 * anyone else up:
 	 */
 	if (!(uval & FUTEX_OWNER_DIED))
-		uval = cmpxchg_futex_value_locked(uaddr, current->pid, 0);
+		uval = cmpxchg_futex_value_locked(uaddr, task_pid_vnr(current), 0);
 
 
 	if (unlikely(uval == -EFAULT))
@@ -1617,7 +1621,7 @@ static int futex_unlock_pi(u32 __user *uaddr, struct rw_semaphore *fshared)
 	 * Rare case: we managed to release the lock atomically,
 	 * no need to wake anyone else up:
 	 */
-	if (unlikely(uval == current->pid))
+	if (unlikely(uval == task_pid_vnr(current)))
 		goto out_unlock;
 
 	/*
@@ -1854,7 +1858,8 @@ sys_get_robust_list(int pid, struct robust_list_head __user * __user *head_ptr,
 
 		ret = -ESRCH;
 		rcu_read_lock();
-		p = find_task_by_pid(pid);
+		p = find_task_by_pid_ns(pid,
+				current->nsproxy->pid_ns);
 		if (!p)
 			goto err_unlock;
 		ret = -EPERM;
@@ -1887,7 +1892,7 @@ int handle_futex_death(u32 __user *uaddr, struct task_struct *curr, int pi)
 	if (get_user(uval, uaddr))
 		return -1;
 
-	if ((uval & FUTEX_TID_MASK) == curr->pid) {
+	if ((uval & FUTEX_TID_MASK) == task_pid_vnr(curr)) {
 		/*
 		 * Ok, this dying thread is truly holding a futex
 		 * of interest. Set the OWNER_DIED bit atomically

kernel/futex_compat.c

@@ -8,6 +8,7 @@
 
 #include <linux/linkage.h>
 #include <linux/compat.h>
+#include <linux/nsproxy.h>
 #include <linux/futex.h>
 
 #include <asm/uaccess.h>
@@ -124,7 +125,8 @@ compat_sys_get_robust_list(int pid, compat_uptr_t __user *head_ptr,
 
 		ret = -ESRCH;
 		read_lock(&tasklist_lock);
-		p = find_task_by_pid(pid);
+		p = find_task_by_pid_ns(pid,
+				current->nsproxy->pid_ns);
 		if (!p)
 			goto err_unlock;
 		ret = -EPERM;

kernel/ptrace.c

@@ -19,6 +19,7 @@
 #include <linux/security.h>
 #include <linux/signal.h>
 #include <linux/audit.h>
+#include <linux/pid_namespace.h>
 
 #include <asm/pgtable.h>
 #include <asm/uaccess.h>
@@ -443,7 +444,8 @@ struct task_struct *ptrace_get_task_struct(pid_t pid)
 		return ERR_PTR(-EPERM);
 
 	read_lock(&tasklist_lock);
-	child = find_task_by_pid(pid);
+	child = find_task_by_pid_ns(pid,
+			current->nsproxy->pid_ns);
 	if (child)
 		get_task_struct(child);
 

kernel/sched.c

@@ -44,6 +44,7 @@
 #include <linux/vmalloc.h>
 #include <linux/blkdev.h>
 #include <linux/delay.h>
+#include <linux/pid_namespace.h>
 #include <linux/smp.h>
 #include <linux/threads.h>
 #include <linux/timer.h>
@@ -1876,7 +1877,7 @@ asmlinkage void schedule_tail(struct task_struct *prev)
 	preempt_enable();
 #endif
 	if (current->set_child_tid)
-		put_user(current->pid, current->set_child_tid);
+		put_user(task_pid_vnr(current), current->set_child_tid);
 }
 
 /*
@@ -4167,7 +4168,8 @@ struct task_struct *idle_task(int cpu)
  */
 static struct task_struct *find_process_by_pid(pid_t pid)
 {
-	return pid ? find_task_by_pid(pid) : current;
+	return pid ?
+		find_task_by_pid_ns(pid, current->nsproxy->pid_ns) : current;
 }
 
 /* Actually do priority change: must hold rq lock. */

kernel/signal.c

@@ -694,7 +694,7 @@ static int send_signal(int sig, struct siginfo *info, struct task_struct *t,
 			q->info.si_signo = sig;
 			q->info.si_errno = 0;
 			q->info.si_code = SI_USER;
-			q->info.si_pid = current->pid;
+			q->info.si_pid = task_pid_vnr(current);
 			q->info.si_uid = current->uid;
 			break;
 		case (unsigned long) SEND_SIG_PRIV:
@@ -1089,7 +1089,7 @@ kill_proc_info(int sig, struct siginfo *info, pid_t pid)
 {
 	int error;
 	rcu_read_lock();
-	error = kill_pid_info(sig, info, find_pid(pid));
+	error = kill_pid_info(sig, info, find_vpid(pid));
 	rcu_read_unlock();
 	return error;
 }
@@ -1160,9 +1160,9 @@ static int kill_something_info(int sig, struct siginfo *info, int pid)
 		read_unlock(&tasklist_lock);
 		ret = count ? retval : -ESRCH;
 	} else if (pid < 0) {
-		ret = kill_pgrp_info(sig, info, find_pid(-pid));
+		ret = kill_pgrp_info(sig, info, find_vpid(-pid));
 	} else {
-		ret = kill_pid_info(sig, info, find_pid(pid));
+		ret = kill_pid_info(sig, info, find_vpid(pid));
 	}
 	rcu_read_unlock();
 	return ret;
@@ -1266,7 +1266,12 @@ EXPORT_SYMBOL(kill_pid);
 int
 kill_proc(pid_t pid, int sig, int priv)
 {
-	return kill_proc_info(sig, __si_special(priv), pid);
+	int ret;
+
+	rcu_read_lock();
+	ret = kill_pid_info(sig, __si_special(priv), find_pid(pid));
+	rcu_read_unlock();
+	return ret;
 }
 
 /*
@@ -1443,7 +1448,22 @@ void do_notify_parent(struct task_struct *tsk, int sig)
 
 	info.si_signo = sig;
 	info.si_errno = 0;
-	info.si_pid = tsk->pid;
+	/*
+	 * we are under tasklist_lock here so our parent is tied to
+	 * us and cannot exit and release its namespace.
+	 *
+	 * the only it can is to switch its nsproxy with sys_unshare,
+	 * bu uncharing pid namespaces is not allowed, so we'll always
+	 * see relevant namespace
+	 *
+	 * write_lock() currently calls preempt_disable() which is the
+	 * same as rcu_read_lock(), but according to Oleg, this is not
+	 * correct to rely on this
+	 */
+	rcu_read_lock();
+	info.si_pid = task_pid_nr_ns(tsk, tsk->parent->nsproxy->pid_ns);
+	rcu_read_unlock();
+
 	info.si_uid = tsk->uid;
 
 	/* FIXME: find out whether or not this is supposed to be c*time. */
@@ -1508,7 +1528,13 @@ static void do_notify_parent_cldstop(struct task_struct *tsk, int why)
 
 	info.si_signo = SIGCHLD;
 	info.si_errno = 0;
-	info.si_pid = tsk->pid;
+	/*
+	 * see comment in do_notify_parent() abot the following 3 lines
+	 */
+	rcu_read_lock();
+	info.si_pid = task_pid_nr_ns(tsk, tsk->parent->nsproxy->pid_ns);
+	rcu_read_unlock();
+
 	info.si_uid = tsk->uid;
 
 	/* FIXME: find out whether or not this is supposed to be c*time. */
@@ -1634,7 +1660,7 @@ void ptrace_notify(int exit_code)
 	memset(&info, 0, sizeof info);
 	info.si_signo = SIGTRAP;
 	info.si_code = exit_code;
-	info.si_pid = current->pid;
+	info.si_pid = task_pid_vnr(current);
 	info.si_uid = current->uid;
 
 	/* Let the debugger run.  */
@@ -1804,7 +1830,7 @@ int get_signal_to_deliver(siginfo_t *info, struct k_sigaction *return_ka,
 				info->si_signo = signr;
 				info->si_errno = 0;
 				info->si_code = SI_USER;
-				info->si_pid = current->parent->pid;
+				info->si_pid = task_pid_vnr(current->parent);
 				info->si_uid = current->parent->uid;
 			}
 
@@ -2191,7 +2217,7 @@ sys_kill(int pid, int sig)
 	info.si_signo = sig;
 	info.si_errno = 0;
 	info.si_code = SI_USER;
-	info.si_pid = current->tgid;
+	info.si_pid = task_tgid_vnr(current);
 	info.si_uid = current->uid;
 
 	return kill_something_info(sig, &info, pid);
@@ -2207,12 +2233,12 @@ static int do_tkill(int tgid, int pid, int sig)
 	info.si_signo = sig;
 	info.si_errno = 0;
 	info.si_code = SI_TKILL;
-	info.si_pid = current->tgid;
+	info.si_pid = task_tgid_vnr(current);
 	info.si_uid = current->uid;
 
 	read_lock(&tasklist_lock);
-	p = find_task_by_pid(pid);
-	if (p && (tgid <= 0 || p->tgid == tgid)) {
+	p = find_task_by_pid_ns(pid, current->nsproxy->pid_ns);
+	if (p && (tgid <= 0 || task_tgid_vnr(p) == tgid)) {
 		error = check_kill_permission(sig, &info, p);
 		/*
 		 * The null signal is a permissions and process existence

kernel/sys.c

@@ -152,7 +152,8 @@ asmlinkage long sys_setpriority(int which, int who, int niceval)
 	switch (which) {
 		case PRIO_PROCESS:
 			if (who)
-				p = find_task_by_pid(who);
+				p = find_task_by_pid_ns(who,
+						current->nsproxy->pid_ns);
 			else
 				p = current;
 			if (p)
@@ -160,7 +161,7 @@ asmlinkage long sys_setpriority(int which, int who, int niceval)
 			break;
 		case PRIO_PGRP:
 			if (who)
-				pgrp = find_pid(who);
+				pgrp = find_vpid(who);
 			else
 				pgrp = task_pgrp(current);
 			do_each_pid_task(pgrp, PIDTYPE_PGID, p) {
@@ -209,7 +210,8 @@ asmlinkage long sys_getpriority(int which, int who)
 	switch (which) {
 		case PRIO_PROCESS:
 			if (who)
-				p = find_task_by_pid(who);
+				p = find_task_by_pid_ns(who,
+						current->nsproxy->pid_ns);
 			else
 				p = current;
 			if (p) {
@@ -220,7 +222,7 @@ asmlinkage long sys_getpriority(int which, int who)
 			break;
 		case PRIO_PGRP:
 			if (who)
-				pgrp = find_pid(who);
+				pgrp = find_vpid(who);
 			else
 				pgrp = task_pgrp(current);
 			do_each_pid_task(pgrp, PIDTYPE_PGID, p) {
@@ -917,9 +919,10 @@ asmlinkage long sys_setpgid(pid_t pid, pid_t pgid)
 	struct task_struct *p;
 	struct task_struct *group_leader = current->group_leader;
 	int err = -EINVAL;
+	struct pid_namespace *ns;
 
 	if (!pid)
-		pid = group_leader->pid;
+		pid = task_pid_vnr(group_leader);
 	if (!pgid)
 		pgid = pid;
 	if (pgid < 0)
@@ -928,10 +931,12 @@ asmlinkage long sys_setpgid(pid_t pid, pid_t pgid)
 	/* From this point forward we keep holding onto the tasklist lock
 	 * so that our parent does not change from under us. -DaveM
 	 */
+	ns = current->nsproxy->pid_ns;
+
 	write_lock_irq(&tasklist_lock);
 
 	err = -ESRCH;
-	p = find_task_by_pid(pid);
+	p = find_task_by_pid_ns(pid, ns);
 	if (!p)
 		goto out;
 
@@ -957,9 +962,9 @@ asmlinkage long sys_setpgid(pid_t pid, pid_t pgid)
 		goto out;
 
 	if (pgid != pid) {
-		struct task_struct *g =
-			find_task_by_pid_type(PIDTYPE_PGID, pgid);
+		struct task_struct *g;
 
+		g = find_task_by_pid_type_ns(PIDTYPE_PGID, pgid, ns);
 		if (!g || task_session(g) != task_session(group_leader))
 			goto out;
 	}
@@ -968,10 +973,13 @@ asmlinkage long sys_setpgid(pid_t pid, pid_t pgid)
 	if (err)
 		goto out;
 
-	if (task_pgrp_nr(p) != pgid) {
+	if (task_pgrp_nr_ns(p, ns) != pgid) {
+		struct pid *pid;
+
 		detach_pid(p, PIDTYPE_PGID);
-		p->signal->pgrp = pgid;
-		attach_pid(p, PIDTYPE_PGID, find_pid(pgid));
+		pid = find_vpid(pgid);
+		attach_pid(p, PIDTYPE_PGID, pid);
+		p->signal->pgrp = pid_nr(pid);
 	}
 
 	err = 0;
@@ -984,19 +992,21 @@ asmlinkage long sys_setpgid(pid_t pid, pid_t pgid)
 asmlinkage long sys_getpgid(pid_t pid)
 {
 	if (!pid)
-		return task_pgrp_nr(current);
+		return task_pgrp_vnr(current);
 	else {
 		int retval;
 		struct task_struct *p;
+		struct pid_namespace *ns;
 
-		read_lock(&tasklist_lock);
-		p = find_task_by_pid(pid);
+		ns = current->nsproxy->pid_ns;
 
+		read_lock(&tasklist_lock);
+		p = find_task_by_pid_ns(pid, ns);
 		retval = -ESRCH;
 		if (p) {
 			retval = security_task_getpgid(p);
 			if (!retval)
-				retval = task_pgrp_nr(p);
+				retval = task_pgrp_nr_ns(p, ns);
 		}
 		read_unlock(&tasklist_lock);
 		return retval;
@@ -1008,7 +1018,7 @@ asmlinkage long sys_getpgid(pid_t pid)
 asmlinkage long sys_getpgrp(void)
 {
 	/* SMP - assuming writes are word atomic this is fine */
-	return task_pgrp_nr(current);
+	return task_pgrp_vnr(current);
 }
 
 #endif
@@ -1016,19 +1026,21 @@ asmlinkage long sys_getpgrp(void)
 asmlinkage long sys_getsid(pid_t pid)
 {
 	if (!pid)
-		return task_session_nr(current);
+		return task_session_vnr(current);
 	else {
 		int retval;
 		struct task_struct *p;
+		struct pid_namespace *ns;
 
-		read_lock(&tasklist_lock);
-		p = find_task_by_pid(pid);
+		ns = current->nsproxy->pid_ns;
 
+		read_lock(&tasklist_lock);
+		p = find_task_by_pid_ns(pid, ns);
 		retval = -ESRCH;
 		if (p) {
 			retval = security_task_getsid(p);
 			if (!retval)
-				retval = task_session_nr(p);
+				retval = task_session_nr_ns(p, ns);
 		}
 		read_unlock(&tasklist_lock);
 		return retval;
@@ -1065,7 +1077,7 @@ asmlinkage long sys_setsid(void)
 	group_leader->signal->tty = NULL;
 	spin_unlock(&group_leader->sighand->siglock);
 
-	err = task_pgrp_nr(group_leader);
+	err = task_pgrp_vnr(group_leader);
 out:
 	write_unlock_irq(&tasklist_lock);
 	return err;

kernel/sysctl.c

@@ -2278,7 +2278,7 @@ static int proc_do_cad_pid(struct ctl_table *table, int write, struct file *filp
 	pid_t tmp;
 	int r;
 
-	tmp = pid_nr(cad_pid);
+	tmp = pid_nr_ns(cad_pid, current->nsproxy->pid_ns);
 
 	r = __do_proc_dointvec(&tmp, table, write, filp, buffer,
 			       lenp, ppos, NULL, NULL);

kernel/timer.c

@@ -26,6 +26,7 @@
 #include <linux/init.h>
 #include <linux/mm.h>
 #include <linux/swap.h>
+#include <linux/pid_namespace.h>
 #include <linux/notifier.h>
 #include <linux/thread_info.h>
 #include <linux/time.h>
@@ -956,7 +957,7 @@ asmlinkage unsigned long sys_alarm(unsigned int seconds)
  */
 asmlinkage long sys_getpid(void)
 {
-	return current->tgid;
+	return task_tgid_vnr(current);
 }
 
 /*
@@ -970,7 +971,7 @@ asmlinkage long sys_getppid(void)
 	int pid;
 
 	rcu_read_lock();
-	pid = rcu_dereference(current->real_parent)->tgid;
+	pid = task_ppid_nr_ns(current, current->nsproxy->pid_ns);
 	rcu_read_unlock();
 
 	return pid;
@@ -1102,7 +1103,7 @@ EXPORT_SYMBOL(schedule_timeout_uninterruptible);
 /* Thread ID - the internal kernel "pid" */
 asmlinkage long sys_gettid(void)
 {
-	return current->pid;
+	return task_pid_vnr(current);
 }
 
 /**

mm/mempolicy.c

@@ -78,6 +78,7 @@
 #include <linux/slab.h>
 #include <linux/string.h>
 #include <linux/module.h>
+#include <linux/nsproxy.h>
 #include <linux/interrupt.h>
 #include <linux/init.h>
 #include <linux/compat.h>
@@ -940,7 +941,8 @@ asmlinkage long sys_migrate_pages(pid_t pid, unsigned long maxnode,
 
 	/* Find the mm_struct */
 	read_lock(&tasklist_lock);
-	task = pid ? find_task_by_pid(pid) : current;
+	task = pid ?
+		find_task_by_pid_ns(pid, current->nsproxy->pid_ns) : current;
 	if (!task) {
 		read_unlock(&tasklist_lock);
 		return -ESRCH;

mm/migrate.c

@@ -19,6 +19,7 @@
 #include <linux/pagemap.h>
 #include <linux/buffer_head.h>
 #include <linux/mm_inline.h>
+#include <linux/nsproxy.h>
 #include <linux/pagevec.h>
 #include <linux/rmap.h>
 #include <linux/topology.h>
@@ -924,7 +925,8 @@ asmlinkage long sys_move_pages(pid_t pid, unsigned long nr_pages,
 
 	/* Find the mm_struct */
 	read_lock(&tasklist_lock);
-	task = pid ? find_task_by_pid(pid) : current;
+	task = pid ?
+		find_task_by_pid_ns(pid, current->nsproxy->pid_ns) : current;
 	if (!task) {
 		read_unlock(&tasklist_lock);
 		return -ESRCH;

net/core/scm.c

@@ -24,6 +24,8 @@
 #include <linux/interrupt.h>
 #include <linux/netdevice.h>
 #include <linux/security.h>
+#include <linux/pid.h>
+#include <linux/nsproxy.h>
 
 #include <asm/system.h>
 #include <asm/uaccess.h>
@@ -42,7 +44,7 @@
 
 static __inline__ int scm_check_creds(struct ucred *creds)
 {
-	if ((creds->pid == current->tgid || capable(CAP_SYS_ADMIN)) &&
+	if ((creds->pid == task_tgid_vnr(current) || capable(CAP_SYS_ADMIN)) &&
 	    ((creds->uid == current->uid || creds->uid == current->euid ||
 	      creds->uid == current->suid) || capable(CAP_SETUID)) &&
 	    ((creds->gid == current->gid || creds->gid == current->egid ||

net/unix/af_unix.c

@@ -483,7 +483,7 @@ static int unix_listen(struct socket *sock, int backlog)
 	sk->sk_max_ack_backlog	= backlog;
 	sk->sk_state		= TCP_LISTEN;
 	/* set credentials so connect can copy them */
-	sk->sk_peercred.pid	= current->tgid;
+	sk->sk_peercred.pid	= task_tgid_vnr(current);
 	sk->sk_peercred.uid	= current->euid;
 	sk->sk_peercred.gid	= current->egid;
 	err = 0;
@@ -1133,7 +1133,7 @@ static int unix_stream_connect(struct socket *sock, struct sockaddr *uaddr,
 	unix_peer(newsk)	= sk;
 	newsk->sk_state		= TCP_ESTABLISHED;
 	newsk->sk_type		= sk->sk_type;
-	newsk->sk_peercred.pid	= current->tgid;
+	newsk->sk_peercred.pid	= task_tgid_vnr(current);
 	newsk->sk_peercred.uid	= current->euid;
 	newsk->sk_peercred.gid	= current->egid;
 	newu = unix_sk(newsk);
@@ -1194,7 +1194,7 @@ static int unix_socketpair(struct socket *socka, struct socket *sockb)
 	sock_hold(skb);
 	unix_peer(ska)=skb;
 	unix_peer(skb)=ska;
-	ska->sk_peercred.pid = skb->sk_peercred.pid = current->tgid;
+	ska->sk_peercred.pid = skb->sk_peercred.pid = task_tgid_vnr(current);
 	ska->sk_peercred.uid = skb->sk_peercred.uid = current->euid;
 	ska->sk_peercred.gid = skb->sk_peercred.gid = current->egid;