From 438dcd5aa3c7842b671895317780f3e373843f86 Mon Sep 17 00:00:00 2001
From: "Eric W. Biederman" <ebiederm@xmission.com>
Date: Wed, 28 Nov 2007 16:21:26 -0800
Subject: [PATCH] --- yaml --- r: 74351 b: refs/heads/master c:
 19fd4bb2a0cfede054e4904e0b167e0ca4f36cc7 h: refs/heads/master i:   74349:
 3b76f767a39478954f54798aaf63c8e2f4257ac2   74347:
 6ac47b1a6bd25d060c25a486e9543b58cd5ba69e   74343:
 faf90db35839f83bad9a3be684094f385ccef0f1   74335:
 1c695d89d1522da654ba470e7852e73c851be924 v: v3

---
 [refs]               |  2 +-
 trunk/fs/proc/base.c | 51 ++++++++++++++++++++++++--------------------
 2 files changed, 29 insertions(+), 24 deletions(-)

diff --git a/[refs] b/[refs]
index 3280ae503e08..0f3370453750 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: c895078355b6b6e05c60aa205892526dd3390f0a
+refs/heads/master: 19fd4bb2a0cfede054e4904e0b167e0ca4f36cc7
diff --git a/trunk/fs/proc/base.c b/trunk/fs/proc/base.c
index a17c26859074..02a63ac04178 100644
--- a/trunk/fs/proc/base.c
+++ b/trunk/fs/proc/base.c
@@ -2411,19 +2411,23 @@ 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,
-		struct pid_namespace *ns)
-{
+struct tgid_iter {
+	unsigned int tgid;
 	struct task_struct *task;
+};
+static struct tgid_iter next_tgid(struct pid_namespace *ns, struct tgid_iter iter)
+{
 	struct pid *pid;
 
+	if (iter.task)
+		put_task_struct(iter.task);
 	rcu_read_lock();
 retry:
-	task = NULL;
-	pid = find_ge_pid(tgid, ns);
+	iter.task = NULL;
+	pid = find_ge_pid(iter.tgid, ns);
 	if (pid) {
-		tgid = pid_nr_ns(pid, ns) + 1;
-		task = pid_task(pid, PIDTYPE_PID);
+		iter.tgid = pid_nr_ns(pid, ns);
+		iter.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
 		 * being a thread_group_leader is the obvious thing
@@ -2436,23 +2440,25 @@ static struct task_struct *next_tgid(unsigned int tgid,
 		 * found doesn't happen to be a thread group leader.
 		 * As we don't care in the case of readdir.
 		 */
-		if (!task || !has_group_leader_pid(task))
+		if (!iter.task || !has_group_leader_pid(iter.task)) {
+			iter.tgid += 1;
 			goto retry;
-		get_task_struct(task);
+		}
+		get_task_struct(iter.task);
 	}
 	rcu_read_unlock();
-	return task;
+	return iter;
 }
 
 #define TGID_OFFSET (FIRST_PROCESS_ENTRY + ARRAY_SIZE(proc_base_stuff))
 
 static int proc_pid_fill_cache(struct file *filp, void *dirent, filldir_t filldir,
-	struct task_struct *task, int tgid)
+	struct tgid_iter iter)
 {
 	char name[PROC_NUMBUF];
-	int len = snprintf(name, sizeof(name), "%d", tgid);
+	int len = snprintf(name, sizeof(name), "%d", iter.tgid);
 	return proc_fill_cache(filp, dirent, filldir, name, len,
-				proc_pid_instantiate, task, NULL);
+				proc_pid_instantiate, iter.task, NULL);
 }
 
 /* for the /proc/ directory itself, after non-process stuff has been done */
@@ -2460,8 +2466,7 @@ int proc_pid_readdir(struct file * filp, void * dirent, filldir_t filldir)
 {
 	unsigned int nr = filp->f_pos - FIRST_PROCESS_ENTRY;
 	struct task_struct *reaper = get_proc_task(filp->f_path.dentry->d_inode);
-	struct task_struct *task;
-	int tgid;
+	struct tgid_iter iter;
 	struct pid_namespace *ns;
 
 	if (!reaper)
@@ -2474,14 +2479,14 @@ int proc_pid_readdir(struct file * filp, void * dirent, filldir_t filldir)
 	}
 
 	ns = filp->f_dentry->d_sb->s_fs_info;
-	tgid = filp->f_pos - TGID_OFFSET;
-	for (task = next_tgid(tgid, ns);
-	     task;
-	     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);
+	iter.task = NULL;
+	iter.tgid = filp->f_pos - TGID_OFFSET;
+	for (iter = next_tgid(ns, iter);
+	     iter.task;
+	     iter.tgid += 1, iter = next_tgid(ns, iter)) {
+		filp->f_pos = iter.tgid + TGID_OFFSET;
+		if (proc_pid_fill_cache(filp, dirent, filldir, iter) < 0) {
+			put_task_struct(iter.task);
 			goto out;
 		}
 	}