1 files changed, 25 insertions, 14 deletions

diff --git a/kernel/fork.c b/kernel/fork.c
index 06d759ab4c62..0f69a3e5281e 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -326,8 +326,8 @@ static void account_kernel_stack(struct task_struct *tsk, int account)
 		}
 
 		/* All stack pages belong to the same memcg. */
-		memcg_kmem_update_page_stat(vm->pages[0], MEMCG_KERNEL_STACK_KB,
-					    account * (THREAD_SIZE / 1024));
+		mod_memcg_page_state(vm->pages[0], MEMCG_KERNEL_STACK_KB,
+				     account * (THREAD_SIZE / 1024));
 	} else {
 		/*
 		 * All stack pages are in the same zone and belong to the
@@ -338,8 +338,8 @@ static void account_kernel_stack(struct task_struct *tsk, int account)
 		mod_zone_page_state(page_zone(first_page), NR_KERNEL_STACK_KB,
 				    THREAD_SIZE / 1024 * account);
 
-		memcg_kmem_update_page_stat(first_page, MEMCG_KERNEL_STACK_KB,
-					    account * (THREAD_SIZE / 1024));
+		mod_memcg_page_state(first_page, MEMCG_KERNEL_STACK_KB,
+				     account * (THREAD_SIZE / 1024));
 	}
 }
 
@@ -1577,6 +1577,18 @@ static __latent_entropy struct task_struct *copy_process(
 	if (!p)
 		goto fork_out;
 
+	/*
+	 * This _must_ happen before we call free_task(), i.e. before we jump
+	 * to any of the bad_fork_* labels. This is to avoid freeing
+	 * p->set_child_tid which is (ab)used as a kthread's data pointer for
+	 * kernel threads (PF_KTHREAD).
+	 */
+	p->set_child_tid = (clone_flags & CLONE_CHILD_SETTID) ? child_tidptr : NULL;
+	/*
+	 * Clear TID on mm_release()?
+	 */
+	p->clear_child_tid = (clone_flags & CLONE_CHILD_CLEARTID) ? child_tidptr : NULL;
+
 	ftrace_graph_init_task(p);
 
 	rt_mutex_init_task(p);
@@ -1625,9 +1637,9 @@ static __latent_entropy struct task_struct *copy_process(
 	prev_cputime_init(&p->prev_cputime);
 
 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
-	seqcount_init(&p->vtime_seqcount);
-	p->vtime_snap = 0;
-	p->vtime_snap_whence = VTIME_INACTIVE;
+	seqcount_init(&p->vtime.seqcount);
+	p->vtime.starttime = 0;
+	p->vtime.state = VTIME_INACTIVE;
 #endif
 
 #if defined(SPLIT_RSS_COUNTING)
@@ -1743,11 +1755,6 @@ static __latent_entropy struct task_struct *copy_process(
 		}
 	}
 
-	p->set_child_tid = (clone_flags & CLONE_CHILD_SETTID) ? child_tidptr : NULL;
-	/*
-	 * Clear TID on mm_release()?
-	 */
-	p->clear_child_tid = (clone_flags & CLONE_CHILD_CLEARTID) ? child_tidptr : NULL;
 #ifdef CONFIG_BLOCK
 	p->plug = NULL;
 #endif
@@ -1845,11 +1852,13 @@ static __latent_entropy struct task_struct *copy_process(
 	*/
 	recalc_sigpending();
 	if (signal_pending(current)) {
-		spin_unlock(&current->sighand->siglock);
-		write_unlock_irq(&tasklist_lock);
 		retval = -ERESTARTNOINTR;
 		goto bad_fork_cancel_cgroup;
 	}
+	if (unlikely(!(ns_of_pid(pid)->nr_hashed & PIDNS_HASH_ADDING))) {
+		retval = -ENOMEM;
+		goto bad_fork_cancel_cgroup;
+	}
 
 	if (likely(p->pid)) {
 		ptrace_init_task(p, (clone_flags & CLONE_PTRACE) || trace);
@@ -1907,6 +1916,8 @@ static __latent_entropy struct task_struct *copy_process(
 	return p;
 
 bad_fork_cancel_cgroup:
+	spin_unlock(&current->sighand->siglock);
+	write_unlock_irq(&tasklist_lock);
 	cgroup_cancel_fork(p);
 bad_fork_free_pid:
 	cgroup_threadgroup_change_end(current);