From: Masami Hiramatsu mhiramat@kernel.org
commit fabe38ab6b2bd9418350284c63825f13b8a6abba upstream.
Mark ftrace mcount handler functions nokprobe since probing on these functions with kretprobe pushes return address incorrectly on kretprobe shadow stack.
Reported-by: Francis Deslauriers francis.deslauriers@efficios.com Tested-by: Andrea Righi righi.andrea@gmail.com Signed-off-by: Masami Hiramatsu mhiramat@kernel.org Acked-by: Steven Rostedt rostedt@goodmis.org Acked-by: Steven Rostedt (VMware) rostedt@goodmis.org Cc: Linus Torvalds torvalds@linux-foundation.org Cc: Mathieu Desnoyers mathieu.desnoyers@efficios.com Cc: Peter Zijlstra peterz@infradead.org Cc: Thomas Gleixner tglx@linutronix.de Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/155094062044.6137.6419622920568680640.stgit@devbox Signed-off-by: Ingo Molnar mingo@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- kernel/trace/ftrace.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)
--- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -32,6 +32,7 @@ #include <linux/list.h> #include <linux/hash.h> #include <linux/rcupdate.h> +#include <linux/kprobes.h>
#include <trace/events/sched.h>
@@ -5165,7 +5166,7 @@ static struct ftrace_ops control_ops = { INIT_OPS_HASH(control_ops) };
-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) { @@ -5214,11 +5215,13 @@ static void ftrace_ops_list_func(unsigne { __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
/* @@ -5239,6 +5242,7 @@ static void ftrace_ops_recurs_func(unsig
trace_clear_recursion(bit); } +NOKPROBE_SYMBOL(ftrace_ops_recurs_func);
/** * ftrace_ops_get_func - get the function a trampoline should call