diff mbox series

[v2,4/9] kasan: sw_tags: Support tag widths less than 8 bits

Message ID 20241022015913.3524425-5-samuel.holland@sifive.com (mailing list archive)
State New
Headers show
Series [v2,1/9] kasan: sw_tags: Use arithmetic shift for shadow computation | expand

Commit Message

Samuel Holland Oct. 22, 2024, 1:57 a.m. UTC 
Allow architectures to override KASAN_TAG_KERNEL in asm/kasan.h. This
is needed on RISC-V, which supports 57-bit virtual addresses and 7-bit
pointer tags. For consistency, move the arm64 MTE definition of
KASAN_TAG_MIN to asm/kasan.h, since it is also architecture-dependent;
RISC-V's equivalent extension is expected to support 7-bit hardware
memory tags.

Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
---

(no changes since v1)

 arch/arm64/include/asm/kasan.h   |  6 ++++--
 arch/arm64/include/asm/uaccess.h |  1 +
 include/linux/kasan-tags.h       | 13 ++++++++-----
 3 files changed, 13 insertions(+), 7 deletions(-)

Comments

kernel test robot Oct. 22, 2024, 7:30 p.m. UTC | #1 
Hi Samuel,

kernel test robot noticed the following build errors:

[auto build test ERROR on akpm-mm/mm-everything]
[also build test ERROR on arm64/for-next/core masahiroy-kbuild/for-next masahiroy-kbuild/fixes linus/master v6.12-rc4 next-20241022]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Samuel-Holland/kasan-sw_tags-Use-arithmetic-shift-for-shadow-computation/20241022-100129
base:   https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-everything
patch link:    https://lore.kernel.org/r/20241022015913.3524425-5-samuel.holland%40sifive.com
patch subject: [PATCH v2 4/9] kasan: sw_tags: Support tag widths less than 8 bits
config: sh-allmodconfig (https://download.01.org/0day-ci/archive/20241023/202410230354.sjewoFxA-lkp@intel.com/config)
compiler: sh4-linux-gcc (GCC) 14.1.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20241023/202410230354.sjewoFxA-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202410230354.sjewoFxA-lkp@intel.com/

All errors (new ones prefixed by >>):

   In file included from include/linux/kasan.h:7,
                    from include/linux/mm.h:31,
                    from arch/sh/kernel/asm-offsets.c:14:
>> include/linux/kasan-tags.h:5:10: fatal error: asm/kasan.h: No such file or directory
       5 | #include <asm/kasan.h>
         |          ^~~~~~~~~~~~~
   compilation terminated.
   make[3]: *** [scripts/Makefile.build:102: arch/sh/kernel/asm-offsets.s] Error 1
   make[3]: Target 'prepare' not remade because of errors.
   make[2]: *** [Makefile:1203: prepare0] Error 2
   make[2]: Target 'prepare' not remade because of errors.
   make[1]: *** [Makefile:224: __sub-make] Error 2
   make[1]: Target 'prepare' not remade because of errors.
   make: *** [Makefile:224: __sub-make] Error 2
   make: Target 'prepare' not remade because of errors.


vim +5 include/linux/kasan-tags.h

     4	
   > 5	#include <asm/kasan.h>
     6
kernel test robot Oct. 22, 2024, 7:51 p.m. UTC | #2 
Hi Samuel,

kernel test robot noticed the following build errors:

[auto build test ERROR on akpm-mm/mm-everything]
[also build test ERROR on arm64/for-next/core masahiroy-kbuild/for-next masahiroy-kbuild/fixes linus/master v6.12-rc4 next-20241022]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Samuel-Holland/kasan-sw_tags-Use-arithmetic-shift-for-shadow-computation/20241022-100129
base:   https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-everything
patch link:    https://lore.kernel.org/r/20241022015913.3524425-5-samuel.holland%40sifive.com
patch subject: [PATCH v2 4/9] kasan: sw_tags: Support tag widths less than 8 bits
config: um-allnoconfig (https://download.01.org/0day-ci/archive/20241023/202410230319.eQozBGh7-lkp@intel.com/config)
compiler: clang version 17.0.6 (https://github.com/llvm/llvm-project 6009708b4367171ccdbf4b5905cb6a803753fe18)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20241023/202410230319.eQozBGh7-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202410230319.eQozBGh7-lkp@intel.com/

All errors (new ones prefixed by >>):

   In file included from arch/um/kernel/asm-offsets.c:1:
   In file included from arch/x86/um/shared/sysdep/kernel-offsets.h:5:
   In file included from include/linux/crypto.h:17:
   In file included from include/linux/slab.h:234:
   In file included from include/linux/kasan.h:7:
   In file included from include/linux/kasan-tags.h:5:
>> arch/um/include/asm/kasan.h:19:2: error: "KASAN_SHADOW_SIZE is not defined for this sub-architecture"
      19 | #error "KASAN_SHADOW_SIZE is not defined for this sub-architecture"
         |  ^
   1 error generated.
   make[3]: *** [scripts/Makefile.build:102: arch/um/kernel/asm-offsets.s] Error 1
   make[3]: Target 'prepare' not remade because of errors.
   make[2]: *** [Makefile:1203: prepare0] Error 2
   make[2]: Target 'prepare' not remade because of errors.
   make[1]: *** [Makefile:224: __sub-make] Error 2
   make[1]: Target 'prepare' not remade because of errors.
   make: *** [Makefile:224: __sub-make] Error 2
   make: Target 'prepare' not remade because of errors.


vim +19 arch/um/include/asm/kasan.h

5b301409e8bc5d7 Patricia Alfonso 2022-07-01  12  
5b301409e8bc5d7 Patricia Alfonso 2022-07-01  13  #ifdef CONFIG_X86_64
5b301409e8bc5d7 Patricia Alfonso 2022-07-01  14  #define KASAN_HOST_USER_SPACE_END_ADDR 0x00007fffffffffffUL
5b301409e8bc5d7 Patricia Alfonso 2022-07-01  15  /* KASAN_SHADOW_SIZE is the size of total address space divided by 8 */
5b301409e8bc5d7 Patricia Alfonso 2022-07-01  16  #define KASAN_SHADOW_SIZE ((KASAN_HOST_USER_SPACE_END_ADDR + 1) >> \
5b301409e8bc5d7 Patricia Alfonso 2022-07-01  17  			KASAN_SHADOW_SCALE_SHIFT)
5b301409e8bc5d7 Patricia Alfonso 2022-07-01  18  #else
5b301409e8bc5d7 Patricia Alfonso 2022-07-01 @19  #error "KASAN_SHADOW_SIZE is not defined for this sub-architecture"
5b301409e8bc5d7 Patricia Alfonso 2022-07-01  20  #endif /* CONFIG_X86_64 */
5b301409e8bc5d7 Patricia Alfonso 2022-07-01  21
diff mbox series

Patch

diff --git a/arch/arm64/include/asm/kasan.h b/arch/arm64/include/asm/kasan.h
index e1b57c13f8a4..4ab419df8b93 100644
--- a/arch/arm64/include/asm/kasan.h
+++ b/arch/arm64/include/asm/kasan.h
@@ -6,8 +6,10 @@ 
 
 #include <linux/linkage.h>
 #include <asm/memory.h>
-#include <asm/mte-kasan.h>
-#include <asm/pgtable-types.h>
+
+#ifdef CONFIG_KASAN_HW_TAGS
+#define KASAN_TAG_MIN			0xF0 /* minimum value for random tags */
+#endif
 
 #define arch_kasan_set_tag(addr, tag)	__tag_set(addr, tag)
 #define arch_kasan_reset_tag(addr)	__tag_reset(addr)
diff --git a/arch/arm64/include/asm/uaccess.h b/arch/arm64/include/asm/uaccess.h
index 1aa4ecb73429..8f700a7dd2cd 100644
--- a/arch/arm64/include/asm/uaccess.h
+++ b/arch/arm64/include/asm/uaccess.h
@@ -22,6 +22,7 @@ 
 #include <asm/cpufeature.h>
 #include <asm/mmu.h>
 #include <asm/mte.h>
+#include <asm/mte-kasan.h>
 #include <asm/ptrace.h>
 #include <asm/memory.h>
 #include <asm/extable.h>
diff --git a/include/linux/kasan-tags.h b/include/linux/kasan-tags.h
index 4f85f562512c..e07c896f95d3 100644
--- a/include/linux/kasan-tags.h
+++ b/include/linux/kasan-tags.h
@@ -2,13 +2,16 @@ 
 #ifndef _LINUX_KASAN_TAGS_H
 #define _LINUX_KASAN_TAGS_H
 
+#include <asm/kasan.h>
+
+#ifndef KASAN_TAG_KERNEL
 #define KASAN_TAG_KERNEL	0xFF /* native kernel pointers tag */
-#define KASAN_TAG_INVALID	0xFE /* inaccessible memory tag */
-#define KASAN_TAG_MAX		0xFD /* maximum value for random tags */
+#endif
+
+#define KASAN_TAG_INVALID	(KASAN_TAG_KERNEL - 1) /* inaccessible memory tag */
+#define KASAN_TAG_MAX		(KASAN_TAG_KERNEL - 2) /* maximum value for random tags */
 
-#ifdef CONFIG_KASAN_HW_TAGS
-#define KASAN_TAG_MIN		0xF0 /* minimum value for random tags */
-#else
+#ifndef KASAN_TAG_MIN
 #define KASAN_TAG_MIN		0x00 /* minimum value for random tags */
 #endif