On Mon, 7 Jan 2019 15:55:36 +0100
Andrea Righi <righi.and...@gmail.com> wrote:
> On Mon, Jan 07, 2019 at 10:32:32PM +0900, Masami Hiramatsu wrote:
> > Mark ftrace mcount handler functions nokprobe since
> > probing on these functions with kretprobe pushes
> > return address incorrectly on kretprobe shadow stack.
> >
> > Signed-off-by: Masami Hiramatsu <mhira...@kernel.org>
> > Reported-by: Francis Deslauriers <francis.deslauri...@efficios.com>
> > ---
> > kernel/trace/ftrace.c | 5 ++++-
> > 1 file changed, 4 insertions(+), 1 deletion(-)
> >
> > diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
> > index f0ff24173a0b..ad4babad4a03 100644
> > --- a/kernel/trace/ftrace.c
> > +++ b/kernel/trace/ftrace.c
> > @@ -6250,7 +6250,7 @@ void ftrace_reset_array_ops(struct trace_array *tr)
> > tr->ops->func = ftrace_stub;
> > }
> >
> > -static inline void
> > +static nokprobe_inline void
>
> I think we need to #include <linux/kprobes.h>, otherwise:
>
> CC kernel/trace/ftrace.o
> kernel/trace/ftrace.c:6219:24: error: expected ‘=’, ‘,’, ‘;’, ‘asm’ or
> ‘__attribute__’ before ‘void’
> static nokprobe_inline void
> ^~~~
>
> kernel/trace/ftrace.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
> index 3a58ad280d83..0333241034d5 100644
> --- a/kernel/trace/ftrace.c
> +++ b/kernel/trace/ftrace.c
> @@ -32,6 +32,7 @@
> #include <linux/sort.h>
> #include <linux/list.h>
> #include <linux/hash.h>
> +#include <linux/kprobes.h>
> #include <linux/rcupdate.h>
>
> #include <trace/events/sched.h>
Oops, I missed it while reordering other patches...
Thank you,
>
> Thanks,
> -Andrea
>
> > __ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip,
> > struct ftrace_ops *ignored, struct pt_regs *regs)
> > {
> > @@ -6310,11 +6310,13 @@ static void ftrace_ops_list_func(unsigned long ip,
> > unsigned long parent_ip,
> > {
> > __ftrace_ops_list_func(ip, parent_ip, NULL, regs);
> > }
> > +NOKPROBE_SYMBOL(ftrace_ops_list_func);
> > #else
> > static void ftrace_ops_no_ops(unsigned long ip, unsigned long parent_ip)
> > {
> > __ftrace_ops_list_func(ip, parent_ip, NULL, NULL);
> > }
> > +NOKPROBE_SYMBOL(ftrace_ops_no_ops);
> > #endif
> >
> > /*
> > @@ -6341,6 +6343,7 @@ static void ftrace_ops_assist_func(unsigned long ip,
> > unsigned long parent_ip,
> > preempt_enable_notrace();
> > trace_clear_recursion(bit);
> > }
> > +NOKPROBE_SYMBOL(ftrace_ops_assist_func);
> >
> > /**
> > * ftrace_ops_get_func - get the function a trampoline should call
--
Masami Hiramatsu <mhira...@kernel.org>
