tracehook: tracehook_consider_ignored_signal
This defines tracehook_consider_ignored_signal() has a fine-grained hook
for deciding to prevent the normal short-circuit of sending an ignored
signal, as ptrace does. There is no change, only cleanup.
Signed-off-by: Roland McGrath <roland@redhat.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Reviewed-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/tracehook.h b/include/linux/tracehook.h
index 2d1426f..8cffd34 100644
--- a/include/linux/tracehook.h
+++ b/include/linux/tracehook.h
@@ -312,4 +312,23 @@
ptrace_notify(SIGTRAP);
}
+/**
+ * tracehook_consider_ignored_signal - suppress short-circuit of ignored signal
+ * @task: task receiving the signal
+ * @sig: signal number being sent
+ * @handler: %SIG_IGN or %SIG_DFL
+ *
+ * Return zero iff tracing doesn't care to examine this ignored signal,
+ * so it can short-circuit normal delivery and never even get queued.
+ * Either @handler is %SIG_DFL and @sig's default is ignore, or it's %SIG_IGN.
+ *
+ * Called with @task->sighand->siglock held.
+ */
+static inline int tracehook_consider_ignored_signal(struct task_struct *task,
+ int sig,
+ void __user *handler)
+{
+ return (task_ptrace(task) & PT_PTRACED) != 0;
+}
+
#endif /* <linux/tracehook.h> */