From: Eddy Wu <[email protected]> [ Upstream commit b4e00444cab4c3f3fec876dc0cccc8cbb0d1a948 ]
current->group_leader->exit_signal may change during copy_process() if current->real_parent exits. Move the assignment inside tasklist_lock to avoid the race. Signed-off-by: Eddy Wu <[email protected]> Acked-by: Oleg Nesterov <[email protected]> Signed-off-by: Linus Torvalds <[email protected]> Signed-off-by: Sasha Levin <[email protected]> --- kernel/fork.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/kernel/fork.c b/kernel/fork.c index e3d5963d8c6f5..419fff8eb9e55 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -2100,14 +2100,9 @@ static __latent_entropy struct task_struct *copy_process( /* ok, now we should be set up.. */ p->pid = pid_nr(pid); if (clone_flags & CLONE_THREAD) { - p->exit_signal = -1; p->group_leader = current->group_leader; p->tgid = current->tgid; } else { - if (clone_flags & CLONE_PARENT) - p->exit_signal = current->group_leader->exit_signal; - else - p->exit_signal = args->exit_signal; p->group_leader = p; p->tgid = p->pid; } @@ -2152,9 +2147,14 @@ static __latent_entropy struct task_struct *copy_process( if (clone_flags & (CLONE_PARENT|CLONE_THREAD)) { p->real_parent = current->real_parent; p->parent_exec_id = current->parent_exec_id; + if (clone_flags & CLONE_THREAD) + p->exit_signal = -1; + else + p->exit_signal = current->group_leader->exit_signal; } else { p->real_parent = current; p->parent_exec_id = current->self_exec_id; + p->exit_signal = args->exit_signal; } klp_copy_process(p); -- 2.27.0
