On Tue, 8 Jan 2019 13:44:54 +0900 Masami Hiramatsu mhiramat@kernel.org 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 mhiramat@kernel.org Reported-by: Francis Deslauriers francis.deslauriers@efficios.com Tested-by: Andrea Righi righi.andrea@gmail.com Cc: stable@vger.kernel.org
Acked-by: Steven Rostedt (VMware) rostedt@goodmis.org
-- Steve
- Changes in v2: Fix to include kprobes.h (Thanks Andrea!)
kernel/trace/ftrace.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index f0ff24173a0b..b0774388d52b 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -34,6 +34,7 @@ #include <linux/list.h> #include <linux/hash.h> #include <linux/rcupdate.h> +#include <linux/kprobes.h> #include <trace/events/sched.h> @@ -6250,7 +6251,7 @@ void ftrace_reset_array_ops(struct trace_array *tr) tr->ops->func = ftrace_stub; } -static inline void +static nokprobe_inline void __ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip, struct ftrace_ops *ignored, struct pt_regs *regs) { @@ -6310,11 +6311,13 @@ 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 +6344,7 @@ 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