Re: [PATCHv3 0/2] Stackleak for arm64

[Laura Abbott]

On 07/25/2018 04:49 AM, Will Deacon wrote:
Hi Laura,
On Tue, Jul 24, 2018 at 05:38:07PM +0100, Will Deacon wrote:
On Fri, Jul 20, 2018 at 02:41:52PM -0700, Laura Abbott wrote:
This is the version of stackleak for arm64, hopefully ready for queueing

Thanks. I'll push these into linux-next tomorrow, once I've had a chance
to test my conflict resolution in entry.S.

I've run into a couple of issues with this series:

1. I had to install libmpc-dev to get GCC_PLUGINS to appear, otherwise the
    hostcc check would silently fail. I guess that's a general observation,
    but it might be nice to print a message about the missing dependencies.

2. It breaks arm64 allmodconfig build. Log below.

Please can you take a look at the build failure? Otherwise, the patches
look good to me.

Cheers,

Will

--->8

arch/arm64/kernel/sdei.c: In function ‘on_sdei_normal_stack’:
arch/arm64/kernel/sdei.c:101:7: error: dereferencing pointer to incomplete type 
‘struct stack_info’
    info->low = low;
        ^~
arch/arm64/kernel/sdei.c:103:16: error: ‘STACK_TYPE_SDEI_NORMAL’ undeclared 
(first use in this function); did you mean ‘SCHED_NORMAL’?
    info->type = STACK_TYPE_SDEI_NORMAL;
                 ^~~~~~~~~~~~~~~~~~~~~~
                 SCHED_NORMAL
arch/arm64/kernel/sdei.c:103:16: note: each undeclared identifier is reported 
only once for each function it appears in
arch/arm64/kernel/sdei.c: In function ‘on_sdei_critical_stack’:
arch/arm64/kernel/sdei.c:121:16: error: ‘STACK_TYPE_SDEI_CRITICAL’ undeclared 
(first use in this function)
    info->type = STACK_TYPE_SDEI_CRITICAL;
                 ^~~~~~~~~~~~~~~~~~~~~~~~
arch/arm64/kernel/sdei.c: At top level:
arch/arm64/kernel/sdei.c:127:6: error: conflicting types for ‘_on_sdei_stack’
  bool _on_sdei_stack(unsigned long sp,
       ^~~~~~~~~~~~~~
In file included from ./include/linux/arm_sdei.h:14:0,
                  from arch/arm64/kernel/sdei.c:5:
./arch/arm64/include/asm/sdei.h:45:6: note: previous declaration of 
‘_on_sdei_stack’ was here
  bool _on_sdei_stack(unsigned long sp, struct stack_info *info);
       ^~~~~~~~~~~~~~
arch/arm64/kernel/sdei.c: In function ‘_on_sdei_stack’:
arch/arm64/kernel/sdei.c:136:33: error: ‘info’ undeclared (first use in this 
function); did you mean ‘int’?
   if (on_sdei_critical_stack(sp, info))
                                  ^~~~
                                  int
arch/arm64/kernel/sdei.c:131:21: warning: unused variable ‘high’ 
[-Wunused-variable]
   unsigned long low, high;
                      ^~~~
arch/arm64/kernel/sdei.c:131:16: warning: unused variable ‘low’ 
[-Wunused-variable]
   unsigned long low, high;
                 ^~~
make[1]: *** [arch/arm64/kernel/sdei.o] Error 1
make[1]: *** Waiting for unfinished jobs....
make: *** [arch/arm64/kernel] Error 2


Ugh this was a failure that I missed folding in, sorry about that

--- 8< ----

diff --git a/arch/arm64/kernel/sdei.c b/arch/arm64/kernel/sdei.c
index 7154fee1cb2b..a94a868f0532 100644
--- a/arch/arm64/kernel/sdei.c
+++ b/arch/arm64/kernel/sdei.c
@@ -13,6 +13,7 @@
 #include <asm/mmu.h>
 #include <asm/ptrace.h>
 #include <asm/sections.h>
+#include <asm/stacktrace.h>
 #include <asm/sysreg.h>
 #include <asm/vmap_stack.h>
 
@@ -125,11 +126,8 @@ bool on_sdei_critical_stack(unsigned long sp,
 }
 
 bool _on_sdei_stack(unsigned long sp,
-               unsigned long *stack_low,
-               unsigned long *stack_high)
+               struct stack_info *info)
 {
-       unsigned long low, high;
-
        if (!IS_ENABLED(CONFIG_VMAP_STACK))
                return false;