tmakin/ack-tegra
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

[PATCH] introduce get_task_pid() to fix unsafe get_pid()

Browse Source 
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 <oleg@tv-sign.ru>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Oleg Nesterov
2006-10-02 02:18:59 -07:00
committed by Linus Torvalds
parent 1c0d04c9e4
commit 1a657f78dc
3 changed files with 13 additions and 2 deletions
Download Patch File Download Diff File Expand all files Collapse all files
kernel/pid.c
+9
View File
@@ -304,6 +304,15 @@ struct task_struct *find_task_by_pid_type(int type, int nr)
EXPORT_SYMBOL(find_task_by_pid_type);
struct pid *get_task_pid(struct task_struct *task, enum pid_type type)
{
struct pid *pid;
rcu_read_lock();
pid = get_pid(task->pids[type].pid);
rcu_read_unlock();
return pid;
}
struct task_struct *fastcall get_pid_task(struct pid *pid, enum pid_type type)
{
struct task_struct *result;