diff options
| -rw-r--r-- | kernel/fork.c | 23 |
1 files changed, 20 insertions, 3 deletions
diff --git a/kernel/fork.c b/kernel/fork.c index 182ec2e9087d..4a2080b968c8 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -2108,10 +2108,27 @@ static int __pidfd_prepare(struct pid *pid, unsigned int flags, struct file **re */ int pidfd_prepare(struct pid *pid, unsigned int flags, struct file **ret) { - bool thread = flags & PIDFD_THREAD; + int err = 0; - if (!pid_has_task(pid, thread ? PIDTYPE_PID : PIDTYPE_TGID)) - return -EINVAL; + if (!(flags & PIDFD_THREAD)) { + /* + * If this is struct pid isn't used as a thread-group + * leader pid but the caller requested to create a + * thread-group leader pidfd then report ENOENT to the + * caller as a hint. + */ + if (!pid_has_task(pid, PIDTYPE_TGID)) + err = -ENOENT; + } + + /* + * If this wasn't a thread-group leader struct pid or the task + * got reaped in the meantime report -ESRCH to userspace. + */ + if (!pid_has_task(pid, PIDTYPE_PID)) + err = -ESRCH; + if (err) + return err; return __pidfd_prepare(pid, flags, ret); } |