diff options
| author | Oleg Nesterov <oleg@tv-sign.ru> | 2008-02-08 04:19:09 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2008-02-08 09:22:27 -0800 |
| commit | e4cc0a9c876d4d4eadaef97a2bff4a199946d202 (patch) | |
| tree | e25406d84ce842c54e3ac5438e4bcee32a75a964 /kernel | |
| parent | 4e021306cff4277764a42065214fc73f2d26be4b (diff) | |
fix setsid() for sub-namespace /sbin/init
sys_setsid() still deals with pid_t's from the global namespace. This means
that the "session > 1" check can't help for sub-namespace init, setsid() can't
succeed because copy_process(CLONE_NEWPID) populates PIDTYPE_PGID/SID links.
Remove the usage of task_struct->pid and convert the code to use "struct pid".
This also simplifies and speedups the code, saves one find_pid().
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/sys.c | 22 |
1 files changed, 10 insertions, 12 deletions
diff --git a/kernel/sys.c b/kernel/sys.c index 42136dd453d1..e13bc518b444 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -1045,35 +1045,33 @@ asmlinkage long sys_getsid(pid_t pid) asmlinkage long sys_setsid(void) { struct task_struct *group_leader = current->group_leader; - pid_t session; + struct pid *sid = task_pid(group_leader); + pid_t session = pid_vnr(sid); int err = -EPERM; write_lock_irq(&tasklist_lock); - /* Fail if I am already a session leader */ if (group_leader->signal->leader) goto out; - session = group_leader->pid; - /* Fail if a process group id already exists that equals the - * proposed session id. + /* Fail if a process group id already exists that equals the proposed + * session id. * - * Don't check if session id == 1 because kernel threads use this - * session id and so the check will always fail and make it so - * init cannot successfully call setsid. + * Don't check if session == 1 because kernel threads and CLONE_NEWPID + * tasks use this session id and so the check will always fail and make + * it so init cannot successfully call setsid. */ - if (session > 1 && find_task_by_pid_type_ns(PIDTYPE_PGID, - session, &init_pid_ns)) + if (session != 1 && pid_task(sid, PIDTYPE_PGID)) goto out; group_leader->signal->leader = 1; - __set_special_pids(session, session); + __set_special_pids(pid_nr(sid), pid_nr(sid)); spin_lock(&group_leader->sighand->siglock); group_leader->signal->tty = NULL; spin_unlock(&group_leader->sighand->siglock); - err = task_pgrp_vnr(group_leader); + err = session; out: write_unlock_irq(&tasklist_lock); return err; |