sys_setpgid(): simplify pid/ns interaction
sys_setpgid() does unneeded conversions from pid_t to "struct pid" and vice
versa. Use "struct pid" more consistently. Saves one find_vpid() and
eliminates the explicit usage of ->nsproxy->pid_ns. Imho, cleanups the
code.
Also use the same_thread_group() helper.
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Acked-by: Pavel Emelyanov <xemul@openvz.org>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/kernel/sys.c b/kernel/sys.c
index e3c08d4..42136dd 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -916,8 +916,8 @@
{
struct task_struct *p;
struct task_struct *group_leader = current->group_leader;
- int err = -EINVAL;
- struct pid_namespace *ns;
+ struct pid *pgrp;
+ int err;
if (!pid)
pid = task_pid_vnr(group_leader);
@@ -929,12 +929,10 @@
/* 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_ns(pid, ns);
+ p = find_task_by_vpid(pid);
if (!p)
goto out;
@@ -942,7 +940,7 @@
if (!thread_group_leader(p))
goto out;
- if (p->real_parent->tgid == group_leader->tgid) {
+ if (same_thread_group(p->real_parent, group_leader)) {
err = -EPERM;
if (task_session(p) != task_session(group_leader))
goto out;
@@ -959,10 +957,12 @@
if (p->signal->leader)
goto out;
+ pgrp = task_pid(p);
if (pgid != pid) {
struct task_struct *g;
- g = find_task_by_pid_type_ns(PIDTYPE_PGID, pgid, ns);
+ pgrp = find_vpid(pgid);
+ g = pid_task(pgrp, PIDTYPE_PGID);
if (!g || task_session(g) != task_session(group_leader))
goto out;
}
@@ -971,13 +971,10 @@
if (err)
goto out;
- if (task_pgrp_nr_ns(p, ns) != pgid) {
- struct pid *pid;
-
+ if (task_pgrp(p) != pgrp) {
detach_pid(p, PIDTYPE_PGID);
- pid = find_vpid(pgid);
- attach_pid(p, PIDTYPE_PGID, pid);
- set_task_pgrp(p, pid_nr(pid));
+ attach_pid(p, PIDTYPE_PGID, pgrp);
+ set_task_pgrp(p, pid_nr(pgrp));
}
err = 0;