On Wed, Sep 29, 2021 at 12:03:36PM -0700, Dave Hansen wrote: > On 9/29/21 11:58 AM, Alexander Popov wrote: > > --- a/kernel/panic.c > > +++ b/kernel/panic.c > > @@ -53,6 +53,7 @@ static int pause_on_oops_flag; > > static DEFINE_SPINLOCK(pause_on_oops_lock); > > bool crash_kexec_post_notifiers; > > int panic_on_warn __read_mostly; > > +int pkill_on_warn __read_mostly; I like this idea. I can't tell if Linus would tolerate it, though. But I really have wanted a middle ground like BUG(). Having only WARN() and panic() is not very friendly. :( > > unsigned long panic_on_taint; > > bool panic_on_taint_nousertaint = false; > > > > @@ -610,6 +611,9 @@ void __warn(const char *file, int line, void *caller, unsigned taint, > > > > print_oops_end_marker(); > > > > + if (pkill_on_warn && system_state >= SYSTEM_RUNNING) > > + do_group_exit(SIGKILL); > > + > > /* Just a warning, don't kill lockdep. */ > > add_taint(taint, LOCKDEP_STILL_OK); > > } > > Doesn't this tie into the warning *printing* code? That's better than > nothing, for sure. But, if we're doing this for hardening, I think we > would want to kill anyone provoking a warning, not just the first one > that triggered *printing* the warning. Right, this needs to be moved into the callers of __warn() (i.e. report_bug(), and warn_slowpath_fmt()), likely with some small refactoring in report_bug(). -- Kees Cook
