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Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko From: Maciej Wieczor-Retman Cc: m.wieczorretman@pm.me, Maciej Wieczor-Retman , kasan-dev@googlegroups.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: [PATCH v9 04/13] x86/kasan: Add arch specific kasan functions Message-ID: <764ec564b29372fa7e8cd6cf3ba1f4cfac6ea1d0.1768845098.git.m.wieczorretman@pm.me> In-Reply-To: References: Feedback-ID: 164464600:user:proton X-Pm-Message-ID: 9d53fc9017bfe54371bdd75ce3f16f0f911acc40 MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-Rspamd-Server: rspam11 X-Rspamd-Queue-Id: 22B8C180007 X-Rspam-User: X-Stat-Signature: 31srnmn6r87nzt5fpykehsas3ddn7zp8 X-HE-Tag: 1768920098-638411 X-HE-Meta: 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 qrMwTDGl 1czZ3lWZ1IAwqUdzQd02fYibB9kQGCQcaYg0Fukibj8gfSLjyMNmeV9W/M4gssGJApKYv8wOZ9KQCC0h2v75FOjHv5fKwK/obHw7c9ZpTmMiyLwXcLePX82tuySh2W4JjFWSUui9UWxYPCNXFXWpaSS2HbVyQ8eYtqF/aiXz1P02wtHcaHSEDCGyeJiqKMA/cEcfsGzoQ61WUYDjNi3OvCLD6F0ibanowPGY3weVO2H08wP5XPb54a230bxvAJU744yuGhX8z46r1yzj6TuBuUngp4QGx+QFcpWVrKkrlL/NQpfBk+z9fpJ489GsEJZdIUoP+p2w5+X+iz7AOxJbRuX4XZCybKar2ut4PH3r2i2McIYI= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: From: Maciej Wieczor-Retman KASAN's software tag-based mode needs multiple macros/functions to handle tag and pointer interactions - to set, retrieve and reset tags from the top bits of a pointer. Mimic functions currently used by arm64 but change the tag's position to bits [60:57] in the pointer. Signed-off-by: Maciej Wieczor-Retman Reviewed-by: Andrey Ryabinin --- Changelog v9: - Rename KASAN_TAG_BYTE_MASK to KASAN_TAG_BITS_MASK. - Add Andrey Ryabinin's Reviewed-by tag. Changelog v7: - Add KASAN_TAG_BYTE_MASK to avoid circular includes and avoid removing KASAN_TAG_MASK from mmzone.h. - Remove Andrey's Acked-by tag. Changelog v6: - Remove empty line after ifdef CONFIG_KASAN_SW_TAGS - Add ifdef 64 bit to avoid problems in vdso32. - Add Andrey's Acked-by tag. Changelog v4: - Rewrite __tag_set() without pointless casts and make it more readable. Changelog v3: - Reorder functions so that __tag_*() etc are above the arch_kasan_*() ones. - Remove CONFIG_KASAN condition from __tag_set() arch/x86/include/asm/kasan.h | 42 ++++++++++++++++++++++++++++++++++-- include/linux/kasan-tags.h | 2 ++ include/linux/mmzone.h | 2 +- 3 files changed, 43 insertions(+), 3 deletions(-) diff --git a/arch/x86/include/asm/kasan.h b/arch/x86/include/asm/kasan.h index d7e33c7f096b..c868ae734f68 100644 --- a/arch/x86/include/asm/kasan.h +++ b/arch/x86/include/asm/kasan.h @@ -3,6 +3,8 @@ #define _ASM_X86_KASAN_H =20 #include +#include +#include #define KASAN_SHADOW_OFFSET _AC(CONFIG_KASAN_SHADOW_OFFSET, UL) #define KASAN_SHADOW_SCALE_SHIFT 3 =20 @@ -24,8 +26,43 @@ =09=09=09=09=09=09 KASAN_SHADOW_SCALE_SHIFT))) =20 #ifndef __ASSEMBLER__ +#include +#include +#include + +#ifdef CONFIG_KASAN_SW_TAGS +#define __tag_shifted(tag)=09=09FIELD_PREP(GENMASK_ULL(60, 57), tag) +#define __tag_reset(addr)=09=09(sign_extend64((u64)(addr), 56)) +#define __tag_get(addr)=09=09=09((u8)FIELD_GET(GENMASK_ULL(60, 57), (u64)a= ddr)) +#else +#define __tag_shifted(tag)=09=090UL +#define __tag_reset(addr)=09=09(addr) +#define __tag_get(addr)=09=09=090 +#endif /* CONFIG_KASAN_SW_TAGS */ + +#ifdef CONFIG_64BIT +static inline void *__tag_set(const void *__addr, u8 tag) +{ +=09u64 addr =3D (u64)__addr; + +=09addr &=3D ~__tag_shifted(KASAN_TAG_BITS_MASK); +=09addr |=3D __tag_shifted(tag & KASAN_TAG_BITS_MASK); + +=09return (void *)addr; +} +#else +static inline void *__tag_set(void *__addr, u8 tag) +{ +=09return __addr; +} +#endif + +#define arch_kasan_set_tag(addr, tag)=09__tag_set(addr, tag) +#define arch_kasan_reset_tag(addr)=09__tag_reset(addr) +#define arch_kasan_get_tag(addr)=09__tag_get(addr) =20 #ifdef CONFIG_KASAN + void __init kasan_early_init(void); void __init kasan_init(void); void __init kasan_populate_shadow_for_vaddr(void *va, size_t size, int nid= ); @@ -34,8 +71,9 @@ static inline void kasan_early_init(void) { } static inline void kasan_init(void) { } static inline void kasan_populate_shadow_for_vaddr(void *va, size_t size, =09=09=09=09=09=09 int nid) { } -#endif =20 -#endif +#endif /* CONFIG_KASAN */ + +#endif /* __ASSEMBLER__ */ =20 #endif diff --git a/include/linux/kasan-tags.h b/include/linux/kasan-tags.h index ad5c11950233..36cc4f70674a 100644 --- a/include/linux/kasan-tags.h +++ b/include/linux/kasan-tags.h @@ -10,6 +10,8 @@ #define KASAN_TAG_WIDTH=09=090 #endif =20 +#define KASAN_TAG_BITS_MASK=09((1UL << KASAN_TAG_WIDTH) - 1) + #ifndef KASAN_TAG_KERNEL #define KASAN_TAG_KERNEL=090xFF /* native kernel pointers tag */ #endif diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index 75ef7c9f9307..631200332c45 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -1177,7 +1177,7 @@ static inline bool zone_is_empty(const struct zone *z= one) #define NODES_MASK=09=09((1UL << NODES_WIDTH) - 1) #define SECTIONS_MASK=09=09((1UL << SECTIONS_WIDTH) - 1) #define LAST_CPUPID_MASK=09((1UL << LAST_CPUPID_SHIFT) - 1) -#define KASAN_TAG_MASK=09=09((1UL << KASAN_TAG_WIDTH) - 1) +#define KASAN_TAG_MASK=09=09KASAN_TAG_BITS_MASK #define ZONEID_MASK=09=09((1UL << ZONEID_SHIFT) - 1) =20 static inline enum zone_type memdesc_zonenum(memdesc_flags_t flags) --=20 2.52.0