2020-11-02 16:09:03

by Andrey Konovalov

Subject: [PATCH v7 34/41] kasan, x86, s390: update undef CONFIG_KASAN

With the intoduction of hardware tag-based KASAN some kernel checks of
this kind:

ifdef CONFIG_KASAN

will be updated to:

if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)

x86 and s390 use a trick to #undef CONFIG_KASAN for some of the code
that isn't linked with KASAN runtime and shouldn't have any KASAN
annotations.

Also #undef CONFIG_KASAN_GENERIC with CONFIG_KASAN.

Signed-off-by: Andrey Konovalov <[email protected]>
Signed-off-by: Vincenzo Frascino <[email protected]>
Reviewed-by: Marco Elver <[email protected]>
---
Change-Id: I2a622db0cb86a8feb60c30d8cb09190075be2a90
---
arch/s390/boot/string.c | 1 +
arch/x86/boot/compressed/misc.h | 1 +
2 files changed, 2 insertions(+)

diff --git a/arch/s390/boot/string.c b/arch/s390/boot/string.c
index b11e8108773a..faccb33b462c 100644
--- a/arch/s390/boot/string.c
+++ b/arch/s390/boot/string.c
@@ -3,6 +3,7 @@
#include <linux/kernel.h>
#include <linux/errno.h>
#undef CONFIG_KASAN
+#undef CONFIG_KASAN_GENERIC
#include "../lib/string.c"

int strncmp(const char *cs, const char *ct, size_t count)
diff --git a/arch/x86/boot/compressed/misc.h b/arch/x86/boot/compressed/misc.h
index 6d31f1b4c4d1..652decd6c4fc 100644
--- a/arch/x86/boot/compressed/misc.h
+++ b/arch/x86/boot/compressed/misc.h
@@ -12,6 +12,7 @@
#undef CONFIG_PARAVIRT_XXL
#undef CONFIG_PARAVIRT_SPINLOCKS
#undef CONFIG_KASAN
+#undef CONFIG_KASAN_GENERIC

/* cpu_feature_enabled() cannot be used this early */
#define USE_EARLY_PGTABLE_L5
--
2.29.1.341.ge80a0c044ae-goog

2020-11-04 18:45:43

by Andrey Konovalov

Subject: Re: [PATCH v7 34/41] kasan, x86, s390: update undef CONFIG_KASAN

On Mon, Nov 2, 2020 at 5:05 PM Andrey Konovalov <[email protected]> wrote:
>
> With the intoduction of hardware tag-based KASAN some kernel checks of
> this kind:
>
> ifdef CONFIG_KASAN
>
> will be updated to:
>
> if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
>
> x86 and s390 use a trick to #undef CONFIG_KASAN for some of the code
> that isn't linked with KASAN runtime and shouldn't have any KASAN
> annotations.
>
> Also #undef CONFIG_KASAN_GENERIC with CONFIG_KASAN.
>
> Signed-off-by: Andrey Konovalov <[email protected]>
> Signed-off-by: Vincenzo Frascino <[email protected]>
> Reviewed-by: Marco Elver <[email protected]>
> ---
> Change-Id: I2a622db0cb86a8feb60c30d8cb09190075be2a90
> ---
> arch/s390/boot/string.c | 1 +
> arch/x86/boot/compressed/misc.h | 1 +
> 2 files changed, 2 insertions(+)
>
> diff --git a/arch/s390/boot/string.c b/arch/s390/boot/string.c
> index b11e8108773a..faccb33b462c 100644
> --- a/arch/s390/boot/string.c
> +++ b/arch/s390/boot/string.c
> @@ -3,6 +3,7 @@
> #include <linux/kernel.h>
> #include <linux/errno.h>
> #undef CONFIG_KASAN
> +#undef CONFIG_KASAN_GENERIC
> #include "../lib/string.c"
>
> int strncmp(const char *cs, const char *ct, size_t count)
> diff --git a/arch/x86/boot/compressed/misc.h b/arch/x86/boot/compressed/misc.h
> index 6d31f1b4c4d1..652decd6c4fc 100644
> --- a/arch/x86/boot/compressed/misc.h
> +++ b/arch/x86/boot/compressed/misc.h
> @@ -12,6 +12,7 @@
> #undef CONFIG_PARAVIRT_XXL
> #undef CONFIG_PARAVIRT_SPINLOCKS
> #undef CONFIG_KASAN
> +#undef CONFIG_KASAN_GENERIC
>
> /* cpu_feature_enabled() cannot be used this early */
> #define USE_EARLY_PGTABLE_L5
> --
> 2.29.1.341.ge80a0c044ae-goog
>

Hi Vasily,

Could you give your ack on this patch?

The full series is here:

https://lore.kernel.org/linux-arm-kernel/[email protected]/

Thanks!

2020-11-04 20:40:05

by Vasily Gorbik

Subject: Re: [PATCH v7 34/41] kasan, x86, s390: update undef CONFIG_KASAN

On Mon, Nov 02, 2020 at 05:04:14PM +0100, Andrey Konovalov wrote:
> With the intoduction of hardware tag-based KASAN some kernel checks of
> this kind:
>
> ifdef CONFIG_KASAN
>
> will be updated to:
>
> if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
>
> x86 and s390 use a trick to #undef CONFIG_KASAN for some of the code
> that isn't linked with KASAN runtime and shouldn't have any KASAN
> annotations.
>
> Also #undef CONFIG_KASAN_GENERIC with CONFIG_KASAN.
>
> Signed-off-by: Andrey Konovalov <[email protected]>
> Signed-off-by: Vincenzo Frascino <[email protected]>
> Reviewed-by: Marco Elver <[email protected]>
> ---
> Change-Id: I2a622db0cb86a8feb60c30d8cb09190075be2a90
> ---
> arch/s390/boot/string.c | 1 +
> arch/x86/boot/compressed/misc.h | 1 +
> 2 files changed, 2 insertions(+)
>
> diff --git a/arch/s390/boot/string.c b/arch/s390/boot/string.c
> index b11e8108773a..faccb33b462c 100644
> --- a/arch/s390/boot/string.c
> +++ b/arch/s390/boot/string.c
> @@ -3,6 +3,7 @@
> #include <linux/kernel.h>
> #include <linux/errno.h>
> #undef CONFIG_KASAN
> +#undef CONFIG_KASAN_GENERIC
> #include "../lib/string.c"

for s390 part
Acked-by: Vasily Gorbik <[email protected]>