diff mbox series

[v9,17/44] kasan, arm64: move initialization message

Message ID 619cb0edad35d946c4796976c25bddb5b3eb0c56.1605046192.git.andreyknvl@google.com (mailing list archive)
State New, archived
Headers show
Series [v9,01/44] kasan: drop unnecessary GPL text from comment headers | expand

Commit Message

Andrey Konovalov Nov. 10, 2020, 10:10 p.m. UTC
Software tag-based KASAN mode is fully initialized with kasan_init_tags(),
while the generic mode only requires kasan_init(). Move the
initialization message for tag-based mode into kasan_init_tags().

Also fix pr_fmt() usage for KASAN code: generic.c doesn't need it as it
doesn't use any printing functions; tag-based mode should use "kasan:"
instead of KBUILD_MODNAME (which stands for file name).

Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
---
Change-Id: Iddca9764b30ff0fab1922f26ca9d4f39b6f22673
---
 arch/arm64/include/asm/kasan.h |  9 +++------
 arch/arm64/mm/kasan_init.c     | 13 +++++--------
 mm/kasan/generic.c             |  2 --
 mm/kasan/sw_tags.c             |  4 +++-
 4 files changed, 11 insertions(+), 17 deletions(-)

Comments

Alexander Potapenko Nov. 11, 2020, 3:03 p.m. UTC | #1
On Tue, Nov 10, 2020 at 11:11 PM Andrey Konovalov <andreyknvl@google.com> wrote:
>
> Software tag-based KASAN mode is fully initialized with kasan_init_tags(),
> while the generic mode only requires kasan_init(). Move the
> initialization message for tag-based mode into kasan_init_tags().
>
> Also fix pr_fmt() usage for KASAN code: generic.c doesn't need it as it
> doesn't use any printing functions; tag-based mode should use "kasan:"
> instead of KBUILD_MODNAME (which stands for file name).
>
> Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
> ---
> Change-Id: Iddca9764b30ff0fab1922f26ca9d4f39b6f22673
> ---
>  arch/arm64/include/asm/kasan.h |  9 +++------
>  arch/arm64/mm/kasan_init.c     | 13 +++++--------
>  mm/kasan/generic.c             |  2 --
>  mm/kasan/sw_tags.c             |  4 +++-
>  4 files changed, 11 insertions(+), 17 deletions(-)
>
> diff --git a/arch/arm64/include/asm/kasan.h b/arch/arm64/include/asm/kasan.h
> index f7ea70d02cab..0aaf9044cd6a 100644
> --- a/arch/arm64/include/asm/kasan.h
> +++ b/arch/arm64/include/asm/kasan.h
> @@ -12,14 +12,10 @@
>  #define arch_kasan_reset_tag(addr)     __tag_reset(addr)
>  #define arch_kasan_get_tag(addr)       __tag_get(addr)
>
> -#ifdef CONFIG_KASAN
> -void kasan_init(void);
> -#else
> -static inline void kasan_init(void) { }
> -#endif
> -
>  #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
>
> +void kasan_init(void);
> +
>  /*
>   * KASAN_SHADOW_START: beginning of the kernel virtual addresses.
>   * KASAN_SHADOW_END: KASAN_SHADOW_START + 1/N of kernel virtual addresses,
> @@ -43,6 +39,7 @@ void kasan_copy_shadow(pgd_t *pgdir);
>  asmlinkage void kasan_early_init(void);
>
>  #else
> +static inline void kasan_init(void) { }
>  static inline void kasan_copy_shadow(pgd_t *pgdir) { }
>  #endif
>
> diff --git a/arch/arm64/mm/kasan_init.c b/arch/arm64/mm/kasan_init.c
> index 5172799f831f..e35ce04beed1 100644
> --- a/arch/arm64/mm/kasan_init.c
> +++ b/arch/arm64/mm/kasan_init.c
> @@ -278,17 +278,14 @@ static void __init kasan_init_depth(void)
>         init_task.kasan_depth = 0;
>  }
>
> -#else /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS) */
> -
> -static inline void __init kasan_init_shadow(void) { }
> -
> -static inline void __init kasan_init_depth(void) { }
> -
> -#endif /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */
> -
>  void __init kasan_init(void)
>  {
>         kasan_init_shadow();
>         kasan_init_depth();
> +#if defined(CONFIG_KASAN_GENERIC)
> +       /* CONFIG_KASAN_SW_TAGS also requires kasan_init_tags(). */
>         pr_info("KernelAddressSanitizer initialized\n");
> +#endif
>  }

Cannot we have a single kasan_init() function that will call
tool-specific initialization functions and print the message at the
end?

> +
> +#endif /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */
> diff --git a/mm/kasan/generic.c b/mm/kasan/generic.c
> index e1af3b6c53b8..adb254df1b1d 100644
> --- a/mm/kasan/generic.c
> +++ b/mm/kasan/generic.c
> @@ -9,8 +9,6 @@
>   *        Andrey Konovalov <andreyknvl@gmail.com>
>   */
>
> -#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
> -
>  #include <linux/export.h>
>  #include <linux/interrupt.h>
>  #include <linux/init.h>
> diff --git a/mm/kasan/sw_tags.c b/mm/kasan/sw_tags.c
> index b2638c2cd58a..d25f8641b7cd 100644
> --- a/mm/kasan/sw_tags.c
> +++ b/mm/kasan/sw_tags.c
> @@ -6,7 +6,7 @@
>   * Author: Andrey Konovalov <andreyknvl@google.com>
>   */
>
> -#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
> +#define pr_fmt(fmt) "kasan: " fmt
>
>  #include <linux/export.h>
>  #include <linux/interrupt.h>
> @@ -41,6 +41,8 @@ void kasan_init_tags(void)
>
>         for_each_possible_cpu(cpu)
>                 per_cpu(prng_state, cpu) = (u32)get_cycles();
> +
> +       pr_info("KernelAddressSanitizer initialized\n");
>  }
>
>  /*
> --
> 2.29.2.222.g5d2a92d10f8-goog
>
Andrey Konovalov Nov. 11, 2020, 6:50 p.m. UTC | #2
On Wed, Nov 11, 2020 at 4:04 PM Alexander Potapenko <glider@google.com> wrote:
>
> On Tue, Nov 10, 2020 at 11:11 PM Andrey Konovalov <andreyknvl@google.com> wrote:
> >
> > Software tag-based KASAN mode is fully initialized with kasan_init_tags(),
> > while the generic mode only requires kasan_init(). Move the
> > initialization message for tag-based mode into kasan_init_tags().
> >
> > Also fix pr_fmt() usage for KASAN code: generic.c doesn't need it as it
> > doesn't use any printing functions; tag-based mode should use "kasan:"
> > instead of KBUILD_MODNAME (which stands for file name).
> >
> > Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
> > Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
> > ---
> > Change-Id: Iddca9764b30ff0fab1922f26ca9d4f39b6f22673
> > ---
> >  arch/arm64/include/asm/kasan.h |  9 +++------
> >  arch/arm64/mm/kasan_init.c     | 13 +++++--------
> >  mm/kasan/generic.c             |  2 --
> >  mm/kasan/sw_tags.c             |  4 +++-
> >  4 files changed, 11 insertions(+), 17 deletions(-)
> >
> > diff --git a/arch/arm64/include/asm/kasan.h b/arch/arm64/include/asm/kasan.h
> > index f7ea70d02cab..0aaf9044cd6a 100644
> > --- a/arch/arm64/include/asm/kasan.h
> > +++ b/arch/arm64/include/asm/kasan.h
> > @@ -12,14 +12,10 @@
> >  #define arch_kasan_reset_tag(addr)     __tag_reset(addr)
> >  #define arch_kasan_get_tag(addr)       __tag_get(addr)
> >
> > -#ifdef CONFIG_KASAN
> > -void kasan_init(void);
> > -#else
> > -static inline void kasan_init(void) { }
> > -#endif
> > -
> >  #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
> >
> > +void kasan_init(void);
> > +
> >  /*
> >   * KASAN_SHADOW_START: beginning of the kernel virtual addresses.
> >   * KASAN_SHADOW_END: KASAN_SHADOW_START + 1/N of kernel virtual addresses,
> > @@ -43,6 +39,7 @@ void kasan_copy_shadow(pgd_t *pgdir);
> >  asmlinkage void kasan_early_init(void);
> >
> >  #else
> > +static inline void kasan_init(void) { }
> >  static inline void kasan_copy_shadow(pgd_t *pgdir) { }
> >  #endif
> >
> > diff --git a/arch/arm64/mm/kasan_init.c b/arch/arm64/mm/kasan_init.c
> > index 5172799f831f..e35ce04beed1 100644
> > --- a/arch/arm64/mm/kasan_init.c
> > +++ b/arch/arm64/mm/kasan_init.c
> > @@ -278,17 +278,14 @@ static void __init kasan_init_depth(void)
> >         init_task.kasan_depth = 0;
> >  }
> >
> > -#else /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS) */
> > -
> > -static inline void __init kasan_init_shadow(void) { }
> > -
> > -static inline void __init kasan_init_depth(void) { }
> > -
> > -#endif /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */
> > -
> >  void __init kasan_init(void)
> >  {
> >         kasan_init_shadow();
> >         kasan_init_depth();
> > +#if defined(CONFIG_KASAN_GENERIC)
> > +       /* CONFIG_KASAN_SW_TAGS also requires kasan_init_tags(). */
> >         pr_info("KernelAddressSanitizer initialized\n");
> > +#endif
> >  }
>
> Cannot we have a single kasan_init() function that will call
> tool-specific initialization functions and print the message at the
> end?

Unfortunately no. For different modes we need different functions that
are called in different places in the kernel. E.g. for generic KASAN
we only need kasan_init() to setup shadow pages; for SW tags we also
need kasan_init_sw_tags() which initializes per-cpu state and
finilizes initialization process.
Alexander Potapenko Nov. 12, 2020, 3:09 p.m. UTC | #3
On Wed, Nov 11, 2020 at 7:50 PM Andrey Konovalov <andreyknvl@google.com> wrote:
>
> On Wed, Nov 11, 2020 at 4:04 PM Alexander Potapenko <glider@google.com> wrote:
> >
> > On Tue, Nov 10, 2020 at 11:11 PM Andrey Konovalov <andreyknvl@google.com> wrote:
> > >
> > > Software tag-based KASAN mode is fully initialized with kasan_init_tags(),
> > > while the generic mode only requires kasan_init(). Move the
> > > initialization message for tag-based mode into kasan_init_tags().
> > >
> > > Also fix pr_fmt() usage for KASAN code: generic.c doesn't need it as it
> > > doesn't use any printing functions; tag-based mode should use "kasan:"
> > > instead of KBUILD_MODNAME (which stands for file name).
> > >
> > > Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
> > > Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>

Reviewed-by: Alexander Potapenko <glider@google.com>

> > Cannot we have a single kasan_init() function that will call
> > tool-specific initialization functions and print the message at the
> > end?
>
> Unfortunately no. For different modes we need different functions that
> are called in different places in the kernel. E.g. for generic KASAN
> we only need kasan_init() to setup shadow pages; for SW tags we also
> need kasan_init_sw_tags() which initializes per-cpu state and
> finilizes initialization process.

Ok, got it.
diff mbox series

Patch

diff --git a/arch/arm64/include/asm/kasan.h b/arch/arm64/include/asm/kasan.h
index f7ea70d02cab..0aaf9044cd6a 100644
--- a/arch/arm64/include/asm/kasan.h
+++ b/arch/arm64/include/asm/kasan.h
@@ -12,14 +12,10 @@ 
 #define arch_kasan_reset_tag(addr)	__tag_reset(addr)
 #define arch_kasan_get_tag(addr)	__tag_get(addr)
 
-#ifdef CONFIG_KASAN
-void kasan_init(void);
-#else
-static inline void kasan_init(void) { }
-#endif
-
 #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
 
+void kasan_init(void);
+
 /*
  * KASAN_SHADOW_START: beginning of the kernel virtual addresses.
  * KASAN_SHADOW_END: KASAN_SHADOW_START + 1/N of kernel virtual addresses,
@@ -43,6 +39,7 @@  void kasan_copy_shadow(pgd_t *pgdir);
 asmlinkage void kasan_early_init(void);
 
 #else
+static inline void kasan_init(void) { }
 static inline void kasan_copy_shadow(pgd_t *pgdir) { }
 #endif
 
diff --git a/arch/arm64/mm/kasan_init.c b/arch/arm64/mm/kasan_init.c
index 5172799f831f..e35ce04beed1 100644
--- a/arch/arm64/mm/kasan_init.c
+++ b/arch/arm64/mm/kasan_init.c
@@ -278,17 +278,14 @@  static void __init kasan_init_depth(void)
 	init_task.kasan_depth = 0;
 }
 
-#else /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS) */
-
-static inline void __init kasan_init_shadow(void) { }
-
-static inline void __init kasan_init_depth(void) { }
-
-#endif /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */
-
 void __init kasan_init(void)
 {
 	kasan_init_shadow();
 	kasan_init_depth();
+#if defined(CONFIG_KASAN_GENERIC)
+	/* CONFIG_KASAN_SW_TAGS also requires kasan_init_tags(). */
 	pr_info("KernelAddressSanitizer initialized\n");
+#endif
 }
+
+#endif /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */
diff --git a/mm/kasan/generic.c b/mm/kasan/generic.c
index e1af3b6c53b8..adb254df1b1d 100644
--- a/mm/kasan/generic.c
+++ b/mm/kasan/generic.c
@@ -9,8 +9,6 @@ 
  *        Andrey Konovalov <andreyknvl@gmail.com>
  */
 
-#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
-
 #include <linux/export.h>
 #include <linux/interrupt.h>
 #include <linux/init.h>
diff --git a/mm/kasan/sw_tags.c b/mm/kasan/sw_tags.c
index b2638c2cd58a..d25f8641b7cd 100644
--- a/mm/kasan/sw_tags.c
+++ b/mm/kasan/sw_tags.c
@@ -6,7 +6,7 @@ 
  * Author: Andrey Konovalov <andreyknvl@google.com>
  */
 
-#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+#define pr_fmt(fmt) "kasan: " fmt
 
 #include <linux/export.h>
 #include <linux/interrupt.h>
@@ -41,6 +41,8 @@  void kasan_init_tags(void)
 
 	for_each_possible_cpu(cpu)
 		per_cpu(prng_state, cpu) = (u32)get_cycles();
+
+	pr_info("KernelAddressSanitizer initialized\n");
 }
 
 /*