releases/5.0.4/x86-kprobes-prohibit-probing-on-optprobe-template-code.patch

   1 From 0192e6535ebe9af68614198ced4fd6d37b778ebf Mon Sep 17 00:00:00 2001
   2 From: Masami Hiramatsu <mhiramat@kernel.org>
   3 Date: Wed, 13 Feb 2019 01:11:19 +0900
   4 Subject: x86/kprobes: Prohibit probing on optprobe template code
   5
   6 From: Masami Hiramatsu <mhiramat@kernel.org>
   7
   8 commit 0192e6535ebe9af68614198ced4fd6d37b778ebf upstream.
   9
  10 Prohibit probing on optprobe template code, since it is not
  11 a code but a template instruction sequence. If we modify
  12 this template, copied template must be broken.
  13
  14 Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
  15 Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
  16 Cc: Andrea Righi <righi.andrea@gmail.com>
  17 Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
  18 Cc: Jiri Olsa <jolsa@redhat.com>
  19 Cc: Linus Torvalds <torvalds@linux-foundation.org>
  20 Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
  21 Cc: Peter Zijlstra <peterz@infradead.org>
  22 Cc: Steven Rostedt <rostedt@goodmis.org>
  23 Cc: Thomas Gleixner <tglx@linutronix.de>
  24 Cc: stable@vger.kernel.org
  25 Fixes: 9326638cbee2 ("kprobes, x86: Use NOKPROBE_SYMBOL() instead of __kprobes annotation")
  26 Link: http://lkml.kernel.org/r/154998787911.31052.15274376330136234452.stgit@devbox
  27 Signed-off-by: Ingo Molnar <mingo@kernel.org>
  28 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  29
  30 ---
  31  arch/x86/kernel/kprobes/opt.c |    5 +++++
  32  1 file changed, 5 insertions(+)
  33
  34 --- a/arch/x86/kernel/kprobes/opt.c
  35 +++ b/arch/x86/kernel/kprobes/opt.c
  36 @@ -141,6 +141,11 @@ asm (
  37
  38  void optprobe_template_func(void);
  39  STACK_FRAME_NON_STANDARD(optprobe_template_func);
  40 +NOKPROBE_SYMBOL(optprobe_template_func);
  41 +NOKPROBE_SYMBOL(optprobe_template_entry);
  42 +NOKPROBE_SYMBOL(optprobe_template_val);
  43 +NOKPROBE_SYMBOL(optprobe_template_call);
  44 +NOKPROBE_SYMBOL(optprobe_template_end);
  45
  46  #define TMPL_MOVE_IDX \
  47         ((long)optprobe_template_val - (long)optprobe_template_entry)