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charset=us-ascii Content-Disposition: inline X-Stat-Signature: ug5xwenbtin39h99dix8955q4fd1brbe X-Rspam-User: X-Rspamd-Queue-Id: 79C8340007 X-Rspamd-Server: rspam12 X-HE-Tag: 1773755909-648553 X-HE-Meta: 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 7+7X2Ker fFDOXItIet4NaM1iCsUONqIJr7E65WmQR41qOPhLIMSU7LMNVkdZkLyNYPiu7M2Q4NoXIMoXn1qZyVdibwMNdIds3ZxLcnQrHklgRMLeVQQg+l5ieIprNkKm7jjyNjzYt3QgPu/4NMMTMrUeiXlpuIndaesTqMaS6Eua1zTNiWiXwIoORP/jlHCxQ9wi3yb9+fYJpEorNhLXICf+jE4q6aeJL6p3kwHL3N0CViX8hAu/NRZYq7tT85lJOPpe8hWOUz/HAnNHJBxvvsxO1fvLqBjJ23OgyRixLHg/dB60E3t+lD2w494x4rNPblGO0J39bOzG7KHadKdx50JojVRol6i/s1T/9Y82zfichIvruPo8M+hobLjhq46Fya0fXLgenPBq+ Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: Now that kernel_clone() checks valid_signal(args->exit_signal), the "sig" argument of do_notify_parent() must always be valid or we have a bug. However, do_notify_parent() only checks that sig != -1 at the start, then it does another valid_signal() check before __send_signal_locked(). This is confusing. Change do_notify_parent() to WARN and return early if valid_signal(sig) is false. Signed-off-by: Oleg Nesterov --- kernel/signal.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/kernel/signal.c b/kernel/signal.c index 86aad7badb9a..683ef92f7234 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -2171,7 +2171,8 @@ bool do_notify_parent(struct task_struct *tsk, int sig) bool autoreap = false; u64 utime, stime; - WARN_ON_ONCE(sig == -1); + if (WARN_ON_ONCE(!valid_signal(sig))) + return false; /* do_notify_parent_cldstop should have been called instead. */ WARN_ON_ONCE(task_is_stopped_or_traced(tsk)); @@ -2252,7 +2253,7 @@ bool do_notify_parent(struct task_struct *tsk, int sig) * Send with __send_signal as si_pid and si_uid are in the * parent's namespaces. */ - if (valid_signal(sig) && sig) + if (sig) __send_signal_locked(sig, &info, tsk->parent, PIDTYPE_TGID, false); __wake_up_parent(tsk, tsk->parent); spin_unlock_irqrestore(&psig->siglock, flags); -- 2.52.0