queue-4.14/x86-uaccess-kcov-disable-stack-protector.patch

   1 From 42471536684223f24c8733b0378145017b914389 Mon Sep 17 00:00:00 2001
   2 From: Peter Zijlstra <peterz@infradead.org>
   3 Date: Thu, 7 Mar 2019 19:54:25 +0100
   4 Subject: x86/uaccess, kcov: Disable stack protector
   5
   6 [ Upstream commit 40ea97290b08be2e038b31cbb33097d1145e8169 ]
   7
   8 New tooling noticed this mishap:
   9
  10   kernel/kcov.o: warning: objtool: write_comp_data()+0x138: call to __stack_chk_fail() with UACCESS enabled
  11   kernel/kcov.o: warning: objtool: __sanitizer_cov_trace_pc()+0xd9: call to __stack_chk_fail() with UACCESS enabled
  12
  13 All the other instrumentation (KASAN,UBSAN) also have stack protector
  14 disabled.
  15
  16 Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
  17 Cc: Borislav Petkov <bp@alien8.de>
  18 Cc: Josh Poimboeuf <jpoimboe@redhat.com>
  19 Cc: Linus Torvalds <torvalds@linux-foundation.org>
  20 Cc: Peter Zijlstra <peterz@infradead.org>
  21 Cc: Thomas Gleixner <tglx@linutronix.de>
  22 Signed-off-by: Ingo Molnar <mingo@kernel.org>
  23 Signed-off-by: Sasha Levin <sashal@kernel.org>
  24 ---
  25  kernel/Makefile | 1 +
  26  1 file changed, 1 insertion(+)
  27
  28 diff --git a/kernel/Makefile b/kernel/Makefile
  29 index 172d151d429c..3085141c055c 100644
  30 --- a/kernel/Makefile
  31 +++ b/kernel/Makefile
  32 @@ -30,6 +30,7 @@ KCOV_INSTRUMENT_extable.o := n
  33  # Don't self-instrument.
  34  KCOV_INSTRUMENT_kcov.o := n
  35  KASAN_SANITIZE_kcov.o := n
  36 +CFLAGS_kcov.o := $(call cc-option, -fno-conserve-stack -fno-stack-protector)
  37
  38  # cond_syscall is currently not LTO compatible
  39  CFLAGS_sys_ni.o = $(DISABLE_LTO)
  40 --
  41 2.20.1
  42