ptrace: kill trivial tracehooks
At this point, tracehooks aren't useful to mainline kernel and mostly
just add an extra layer of obfuscation. Although they have comments,
without actual in-kernel users, it is difficult to tell what are their
assumptions and they're actually trying to achieve. To mainline
kernel, they just aren't worth keeping around.
This patch kills the following trivial tracehooks.
* Ones testing whether task is ptraced. Replace with ->ptrace test.
tracehook_expect_breakpoints()
tracehook_consider_ignored_signal()
tracehook_consider_fatal_signal()
* ptrace_event() wrappers. Call directly.
tracehook_report_exec()
tracehook_report_exit()
tracehook_report_vfork_done()
* ptrace_release_task() wrapper. Call directly.
tracehook_finish_release_task()
* noop
tracehook_prepare_release_task()
tracehook_report_death()
This doesn't introduce any behavior change.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
diff --git a/kernel/signal.c b/kernel/signal.c
index 0f33708..1550aee 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -87,7 +87,7 @@
/*
* Tracers may want to know about even ignored signals.
*/
- return !tracehook_consider_ignored_signal(t, sig);
+ return !t->ptrace;
}
/*
@@ -493,7 +493,8 @@
return 1;
if (handler != SIG_IGN && handler != SIG_DFL)
return 0;
- return !tracehook_consider_fatal_signal(tsk, sig);
+ /* if ptraced, let the tracer determine */
+ return !tsk->ptrace;
}
/*
@@ -981,8 +982,7 @@
if (sig_fatal(p, sig) &&
!(signal->flags & (SIGNAL_UNKILLABLE | SIGNAL_GROUP_EXIT)) &&
!sigismember(&t->real_blocked, sig) &&
- (sig == SIGKILL ||
- !tracehook_consider_fatal_signal(t, sig))) {
+ (sig == SIGKILL || !t->ptrace)) {
/*
* This signal will be fatal to the whole group.
*/