From 5b4197cb287daf3cfd008fbf8682a1d6f4b13c0b Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Fri, 29 Apr 2022 10:50:17 -0500 Subject: ptrace: Always take siglock in ptrace_resume Make code analysis simpler and future changes easier by always taking siglock in ptrace_resume. Tested-by: Kees Cook Reviewed-by: Oleg Nesterov Link: https://lkml.kernel.org/r/20220505182645.497868-11-ebiederm@xmission.com Signed-off-by: "Eric W. Biederman" --- kernel/ptrace.c | 13 ++----------- 1 file changed, 2 insertions(+), 11 deletions(-) (limited to 'kernel/ptrace.c') diff --git a/kernel/ptrace.c b/kernel/ptrace.c index 83ed28262708..36a5b7a00d2f 100644 --- a/kernel/ptrace.c +++ b/kernel/ptrace.c @@ -837,8 +837,6 @@ static long ptrace_get_rseq_configuration(struct task_struct *task, static int ptrace_resume(struct task_struct *child, long request, unsigned long data) { - bool need_siglock; - if (!valid_signal(data)) return -EIO; @@ -874,18 +872,11 @@ static int ptrace_resume(struct task_struct *child, long request, * Note that we need siglock even if ->exit_code == data and/or this * status was not reported yet, the new status must not be cleared by * wait_task_stopped() after resume. - * - * If data == 0 we do not care if wait_task_stopped() reports the old - * status and clears the code too; this can't race with the tracee, it - * takes siglock after resume. */ - need_siglock = data && !thread_group_empty(current); - if (need_siglock) - spin_lock_irq(&child->sighand->siglock); + spin_lock_irq(&child->sighand->siglock); child->exit_code = data; wake_up_state(child, __TASK_TRACED); - if (need_siglock) - spin_unlock_irq(&child->sighand->siglock); + spin_unlock_irq(&child->sighand->siglock); return 0; } -- cgit 1.4.1