From 3fee229a8eb936b96933c6b2cd02d2e87a4cc997 Mon Sep 17 00:00:00 2001 From: Tong Tiangen Date: Thu, 12 May 2022 20:23:06 -0700 Subject: [PATCH] riscv/mm: enable ARCH_SUPPORTS_PAGE_TABLE_CHECK As commit d283d422c6c4 ("x86: mm: add x86_64 support for page table check"), enable ARCH_SUPPORTS_PAGE_TABLE_CHECK on riscv. Add additional page table check stubs for page table helpers, these stubs can be used to check the existing page table entries. Link: https://lkml.kernel.org/r/20220507110114.4128854-7-tongtiangen@huawei.com Signed-off-by: Tong Tiangen Reviewed-by: Pasha Tatashin Cc: Anshuman Khandual Cc: Borislav Petkov Cc: Catalin Marinas Cc: Dave Hansen Cc: "H. Peter Anvin" Cc: Ingo Molnar Cc: Kefeng Wang Cc: Palmer Dabbelt Cc: Paul Walmsley Cc: Will Deacon Signed-off-by: Andrew Morton --- arch/riscv/Kconfig | 1 + arch/riscv/include/asm/pgtable.h | 71 ++++++++++++++++++++++++++++++++++++---- 2 files changed, 66 insertions(+), 6 deletions(-) diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 00fd9c5..a228506 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -38,6 +38,7 @@ config RISCV select ARCH_SUPPORTS_ATOMIC_RMW select ARCH_SUPPORTS_DEBUG_PAGEALLOC if MMU select ARCH_SUPPORTS_HUGETLBFS if MMU + select ARCH_SUPPORTS_PAGE_TABLE_CHECK select ARCH_USE_MEMTEST select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU select ARCH_WANT_FRAME_POINTERS diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h index 046b442..62e733c 100644 --- a/arch/riscv/include/asm/pgtable.h +++ b/arch/riscv/include/asm/pgtable.h @@ -114,6 +114,8 @@ #include #endif /* CONFIG_64BIT */ +#include + #ifdef CONFIG_XIP_KERNEL #define XIP_FIXUP(addr) ({ \ uintptr_t __a = (uintptr_t)(addr); \ @@ -315,6 +317,11 @@ static inline int pte_exec(pte_t pte) return pte_val(pte) & _PAGE_EXEC; } +static inline int pte_user(pte_t pte) +{ + return pte_val(pte) & _PAGE_USER; +} + static inline int pte_huge(pte_t pte) { return pte_present(pte) && (pte_val(pte) & _PAGE_LEAF); @@ -446,7 +453,7 @@ static inline void set_pte(pte_t *ptep, pte_t pteval) void flush_icache_pte(pte_t pte); -static inline void set_pte_at(struct mm_struct *mm, +static inline void __set_pte_at(struct mm_struct *mm, unsigned long addr, pte_t *ptep, pte_t pteval) { if (pte_present(pteval) && pte_exec(pteval)) @@ -455,10 +462,17 @@ static inline void set_pte_at(struct mm_struct *mm, set_pte(ptep, pteval); } +static inline void set_pte_at(struct mm_struct *mm, + unsigned long addr, pte_t *ptep, pte_t pteval) +{ + page_table_check_pte_set(mm, addr, ptep, pteval); + __set_pte_at(mm, addr, ptep, pteval); +} + static inline void pte_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep) { - set_pte_at(mm, addr, ptep, __pte(0)); + __set_pte_at(mm, addr, ptep, __pte(0)); } #define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS @@ -479,7 +493,11 @@ static inline int ptep_set_access_flags(struct vm_area_struct *vma, static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long address, pte_t *ptep) { - return __pte(atomic_long_xchg((atomic_long_t *)ptep, 0)); + pte_t pte = __pte(atomic_long_xchg((atomic_long_t *)ptep, 0)); + + page_table_check_pte_clear(mm, address, pte); + + return pte; } #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG @@ -546,6 +564,13 @@ static inline unsigned long pmd_pfn(pmd_t pmd) return ((__pmd_to_phys(pmd) & PMD_MASK) >> PAGE_SHIFT); } +#define __pud_to_phys(pud) (pud_val(pud) >> _PAGE_PFN_SHIFT << PAGE_SHIFT) + +static inline unsigned long pud_pfn(pud_t pud) +{ + return ((__pud_to_phys(pud) & PUD_MASK) >> PAGE_SHIFT); +} + static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot) { return pte_pmd(pte_modify(pmd_pte(pmd), newprot)); @@ -567,6 +592,11 @@ static inline int pmd_young(pmd_t pmd) return pte_young(pmd_pte(pmd)); } +static inline int pmd_user(pmd_t pmd) +{ + return pte_user(pmd_pte(pmd)); +} + static inline pmd_t pmd_mkold(pmd_t pmd) { return pte_pmd(pte_mkold(pmd_pte(pmd))); @@ -600,15 +630,39 @@ static inline pmd_t pmd_mkdirty(pmd_t pmd) static inline void set_pmd_at(struct mm_struct *mm, unsigned long addr, pmd_t *pmdp, pmd_t pmd) { - return set_pte_at(mm, addr, (pte_t *)pmdp, pmd_pte(pmd)); + page_table_check_pmd_set(mm, addr, pmdp, pmd); + return __set_pte_at(mm, addr, (pte_t *)pmdp, pmd_pte(pmd)); +} + +static inline int pud_user(pud_t pud) +{ + return pte_user(pud_pte(pud)); } static inline void set_pud_at(struct mm_struct *mm, unsigned long addr, pud_t *pudp, pud_t pud) { - return set_pte_at(mm, addr, (pte_t *)pudp, pud_pte(pud)); + page_table_check_pud_set(mm, addr, pudp, pud); + return __set_pte_at(mm, addr, (pte_t *)pudp, pud_pte(pud)); +} + +#ifdef CONFIG_PAGE_TABLE_CHECK +static inline bool pte_user_accessible_page(pte_t pte) +{ + return pte_present(pte) && pte_user(pte); +} + +static inline bool pmd_user_accessible_page(pmd_t pmd) +{ + return pmd_leaf(pmd) && pmd_user(pmd); } +static inline bool pud_user_accessible_page(pud_t pud) +{ + return pud_leaf(pud) && pud_user(pud); +} +#endif + #ifdef CONFIG_TRANSPARENT_HUGEPAGE static inline int pmd_trans_huge(pmd_t pmd) { @@ -634,7 +688,11 @@ static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma, static inline pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm, unsigned long address, pmd_t *pmdp) { - return pte_pmd(ptep_get_and_clear(mm, address, (pte_t *)pmdp)); + pmd_t pmd = __pmd(atomic_long_xchg((atomic_long_t *)pmdp, 0)); + + page_table_check_pmd_clear(mm, address, pmd); + + return pmd; } #define __HAVE_ARCH_PMDP_SET_WRPROTECT @@ -648,6 +706,7 @@ static inline void pmdp_set_wrprotect(struct mm_struct *mm, static inline pmd_t pmdp_establish(struct vm_area_struct *vma, unsigned long address, pmd_t *pmdp, pmd_t pmd) { + page_table_check_pmd_set(vma->vm_mm, address, pmdp, pmd); return __pmd(atomic_long_xchg((atomic_long_t *)pmdp, pmd_val(pmd))); } #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ -- 2.7.4