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 âon_sdei_normal_stackâ:
> arch/arm64/kernel/sdei.c:101:7: error: dereferencing pointer to incomplete type âstruct stack_infoâ
>     info->low = low;
>         ^~
> arch/arm64/kernel/sdei.c:103:16: error: âSTACK_TYPE_SDEI_NORMALâ undeclared (first use in this function); did you mean âSCHED_NORMALâ?
>     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 âon_sdei_critical_stackâ:
> arch/arm64/kernel/sdei.c:121:16: error: âSTACK_TYPE_SDEI_CRITICALâ 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 â_on_sdei_stackâ
>   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 â_on_sdei_stackâ was here
>   bool _on_sdei_stack(unsigned long sp, struct stack_info *info);
>        ^~~~~~~~~~~~~~
> arch/arm64/kernel/sdei.c: In function â_on_sdei_stackâ:
> arch/arm64/kernel/sdei.c:136:33: error: âinfoâ undeclared (first use in this function); did you mean âintâ?
>    if (on_sdei_critical_stack(sp, info))
>                                   ^~~~
>                                   int
> arch/arm64/kernel/sdei.c:131:21: warning: unused variable âhighâ [-Wunused-variable]
>    unsigned long low, high;
>                       ^~~~
> arch/arm64/kernel/sdei.c:131:16: warning: unused variable âlowâ [-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;