On Wed, Aug 19, 2020 at 12:44 PM Thomas Gleixner <tglx@xxxxxxxxxxxxx> wrote: > > On Wed, Aug 19 2020 at 10:14, Kyle Huey wrote: > > tl;dr: after 27d6b4d14f5c3ab21c4aef87dd04055a2d7adf14 ptracer > > modifications to orig_ax in a syscall entry trace stop are not honored > > and this breaks our code. > > My fault and I have no idead why none of the silly test cases > noticed. Fix below. That'll do it, thanks. - Kyle > Thanks, > > tglx > --- > diff --git a/kernel/entry/common.c b/kernel/entry/common.c > index 9852e0d62d95..fcae019158ca 100644 > --- a/kernel/entry/common.c > +++ b/kernel/entry/common.c > @@ -65,7 +65,8 @@ static long syscall_trace_enter(struct pt_regs *regs, long syscall, > > syscall_enter_audit(regs, syscall); > > - return ret ? : syscall; > + /* The above might have changed the syscall number */ > + return ret ? : syscall_get_nr(current, regs); > } > > noinstr long syscall_enter_from_user_mode(struct pt_regs *regs, long syscall)
