From 4e021306cff4277764a42065214fc73f2d26be4b Mon Sep 17 00:00:00 2001 From: Oleg Nesterov Date: Fri, 8 Feb 2008 04:19:08 -0800 Subject: [PATCH] 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 Acked-by: Pavel Emelyanov Acked-by: "Eric W. Biederman" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/sys.c | 23 ++++++++++------------- 1 file changed, 10 insertions(+), 13 deletions(-) diff --git a/kernel/sys.c b/kernel/sys.c index e3c08d4324..42136dd453 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -916,8 +916,8 @@ asmlinkage long sys_setpgid(pid_t pid, pid_t pgid) { 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 @@ asmlinkage long sys_setpgid(pid_t pid, pid_t pgid) /* 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 @@ asmlinkage long sys_setpgid(pid_t pid, pid_t pgid) 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 @@ asmlinkage long sys_setpgid(pid_t pid, pid_t pgid) 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 @@ asmlinkage long sys_setpgid(pid_t pid, pid_t pgid) 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; -- 2.39.5