From 1a657f78dcc8ea7c53eaa1f2a45ea2315738c15f Mon Sep 17 00:00:00 2001 From: Oleg Nesterov Date: Mon, 2 Oct 2006 02:18:59 -0700 Subject: [PATCH] introduce get_task_pid() to fix unsafe get_pid() proc_pid_make_inode: ei->pid = get_pid(task_pid(task)); I think this is not safe. get_pid() can be preempted after checking "pid != NULL". Then the task exits, does detach_pid(), and RCU frees the pid. Signed-off-by: Oleg Nesterov Cc: "Eric W. Biederman" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/proc/base.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'fs/proc') diff --git a/fs/proc/base.c b/fs/proc/base.c index a317eb2c444..82da55b5cff 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -958,7 +958,7 @@ static struct inode *proc_pid_make_inode(struct super_block * sb, struct task_st /* * grab the reference to task. */ - ei->pid = get_pid(task_pid(task)); + ei->pid = get_task_pid(task, PIDTYPE_PID); if (!ei->pid) goto out_unlock; @@ -1677,7 +1677,7 @@ static struct dentry *proc_base_instantiate(struct inode *dir, /* * grab the reference to the task. */ - ei->pid = get_pid(task_pid(task)); + ei->pid = get_task_pid(task, PIDTYPE_PID); if (!ei->pid) goto out_iput; -- cgit v1.2.3