From: Rohan McLure <rmclure@xxxxxxxxxxxxx> On creation and clearing of a page table mapping, instrument such calls by invoking page_table_check_pte_set and page_table_check_pte_clear respectively. These calls serve as a sanity check against illegal mappings. Enable ARCH_SUPPORTS_PAGE_TABLE_CHECK for all platforms. See also: riscv support in commit 3fee229a8eb9 ("riscv/mm: enable ARCH_SUPPORTS_PAGE_TABLE_CHECK") arm64 in commit 42b2547137f5 ("arm64/mm: enable ARCH_SUPPORTS_PAGE_TABLE_CHECK") x86_64 in commit d283d422c6c4 ("x86: mm: add x86_64 support for page table check") Reviewed-by: Christophe Leroy <christophe.leroy@xxxxxxxxxx> Signed-off-by: Rohan McLure <rmclure@xxxxxxxxxxxxx> Reviewed-by: Pasha Tatashin <pasha.tatashin@xxxxxxxxxx> [ajd: rebase] Signed-off-by: Andrew Donnellan <ajd@xxxxxxxxxxxxx> --- arch/powerpc/Kconfig | 1 + arch/powerpc/include/asm/book3s/32/pgtable.h | 7 ++- arch/powerpc/include/asm/book3s/64/pgtable.h | 45 +++++++++++++++----- arch/powerpc/include/asm/nohash/pgtable.h | 8 +++- arch/powerpc/mm/book3s64/hash_pgtable.c | 4 ++ arch/powerpc/mm/book3s64/pgtable.c | 11 +++-- arch/powerpc/mm/book3s64/radix_pgtable.c | 3 ++ arch/powerpc/mm/pgtable.c | 4 ++ 8 files changed, 68 insertions(+), 15 deletions(-) diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index 424f188e62d9..a990af9c17aa 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -171,6 +171,7 @@ config PPC select ARCH_STACKWALK select ARCH_SUPPORTS_ATOMIC_RMW select ARCH_SUPPORTS_DEBUG_PAGEALLOC if PPC_BOOK3S || PPC_8xx + select ARCH_SUPPORTS_PAGE_TABLE_CHECK select ARCH_USE_BUILTIN_BSWAP select ARCH_USE_CMPXCHG_LOCKREF if PPC64 select ARCH_USE_MEMTEST diff --git a/arch/powerpc/include/asm/book3s/32/pgtable.h b/arch/powerpc/include/asm/book3s/32/pgtable.h index a2305d850fc9..ad7febf75471 100644 --- a/arch/powerpc/include/asm/book3s/32/pgtable.h +++ b/arch/powerpc/include/asm/book3s/32/pgtable.h @@ -202,6 +202,7 @@ void unmap_kernel_page(unsigned long va); #ifndef __ASSEMBLY__ #include <linux/sched.h> #include <linux/threads.h> +#include <linux/page_table_check.h> /* Bits to mask out from a PGD to get to the PUD page */ #define PGD_MASKED_BITS 0 @@ -315,7 +316,11 @@ static inline int __ptep_test_and_clear_young(struct mm_struct *mm, static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep) { - return __pte(pte_update(mm, addr, ptep, ~_PAGE_HASHPTE, 0, 0)); + pte_t old_pte = __pte(pte_update(mm, addr, ptep, ~_PAGE_HASHPTE, 0, 0)); + + page_table_check_pte_clear(mm, addr, old_pte); + + return old_pte; } #define __HAVE_ARCH_PTEP_SET_WRPROTECT diff --git a/arch/powerpc/include/asm/book3s/64/pgtable.h b/arch/powerpc/include/asm/book3s/64/pgtable.h index 754d4d525f0e..da07d604c275 100644 --- a/arch/powerpc/include/asm/book3s/64/pgtable.h +++ b/arch/powerpc/include/asm/book3s/64/pgtable.h @@ -145,6 +145,8 @@ #define PAGE_KERNEL_ROX __pgprot(_PAGE_BASE | _PAGE_KERNEL_ROX) #ifndef __ASSEMBLY__ +#include <linux/page_table_check.h> + /* * page table defines */ @@ -417,8 +419,11 @@ static inline void huge_ptep_set_wrprotect(struct mm_struct *mm, static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep) { - unsigned long old = pte_update(mm, addr, ptep, ~0UL, 0, 0); - return __pte(old); + pte_t old_pte = __pte(pte_update(mm, addr, ptep, ~0UL, 0, 0)); + + page_table_check_pte_clear(mm, addr, old_pte); + + return old_pte; } #define __HAVE_ARCH_PTEP_GET_AND_CLEAR_FULL @@ -427,11 +432,16 @@ static inline pte_t ptep_get_and_clear_full(struct mm_struct *mm, pte_t *ptep, int full) { if (full && radix_enabled()) { + pte_t old_pte; + /* * We know that this is a full mm pte clear and * hence can be sure there is no parallel set_pte. */ - return radix__ptep_get_and_clear_full(mm, addr, ptep, full); + old_pte = radix__ptep_get_and_clear_full(mm, addr, ptep, full); + page_table_check_pte_clear(mm, addr, old_pte); + + return old_pte; } return ptep_get_and_clear(mm, addr, ptep); } @@ -1309,19 +1319,34 @@ extern int pudp_test_and_clear_young(struct vm_area_struct *vma, static inline pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm, unsigned long addr, pmd_t *pmdp) { - if (radix_enabled()) - return radix__pmdp_huge_get_and_clear(mm, addr, pmdp); - return hash__pmdp_huge_get_and_clear(mm, addr, pmdp); + pmd_t old_pmd; + + if (radix_enabled()) { + old_pmd = radix__pmdp_huge_get_and_clear(mm, addr, pmdp); + } else { + old_pmd = hash__pmdp_huge_get_and_clear(mm, addr, pmdp); + } + + page_table_check_pmd_clear(mm, addr, old_pmd); + + return old_pmd; } #define __HAVE_ARCH_PUDP_HUGE_GET_AND_CLEAR static inline pud_t pudp_huge_get_and_clear(struct mm_struct *mm, unsigned long addr, pud_t *pudp) { - if (radix_enabled()) - return radix__pudp_huge_get_and_clear(mm, addr, pudp); - BUG(); - return *pudp; + pud_t old_pud; + + if (radix_enabled()) { + old_pud = radix__pudp_huge_get_and_clear(mm, addr, pudp); + } else { + BUG(); + } + + page_table_check_pud_clear(mm, addr, old_pud); + + return old_pud; } static inline pmd_t pmdp_collapse_flush(struct vm_area_struct *vma, diff --git a/arch/powerpc/include/asm/nohash/pgtable.h b/arch/powerpc/include/asm/nohash/pgtable.h index 1c3dfe2d6cc1..36c79f39f47d 100644 --- a/arch/powerpc/include/asm/nohash/pgtable.h +++ b/arch/powerpc/include/asm/nohash/pgtable.h @@ -29,6 +29,8 @@ static inline pte_basic_t pte_update(struct mm_struct *mm, unsigned long addr, p #ifndef __ASSEMBLY__ +#include <linux/page_table_check.h> + extern int icache_44x_need_flush; #ifndef pte_huge_size @@ -122,7 +124,11 @@ static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr, static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep) { - return __pte(pte_update(mm, addr, ptep, ~0UL, 0, 0)); + pte_t old_pte = __pte(pte_update(mm, addr, ptep, ~0UL, 0, 0)); + + page_table_check_pte_clear(mm, addr, old_pte); + + return old_pte; } #define __HAVE_ARCH_PTEP_GET_AND_CLEAR diff --git a/arch/powerpc/mm/book3s64/hash_pgtable.c b/arch/powerpc/mm/book3s64/hash_pgtable.c index 988948d69bc1..c1c25d46dd16 100644 --- a/arch/powerpc/mm/book3s64/hash_pgtable.c +++ b/arch/powerpc/mm/book3s64/hash_pgtable.c @@ -8,6 +8,7 @@ #include <linux/sched.h> #include <linux/mm_types.h> #include <linux/mm.h> +#include <linux/page_table_check.h> #include <linux/stop_machine.h> #include <asm/sections.h> @@ -231,6 +232,9 @@ pmd_t hash__pmdp_collapse_flush(struct vm_area_struct *vma, unsigned long addres pmd = *pmdp; pmd_clear(pmdp); + + page_table_check_pmd_clear(vma->vm_mm, address, pmd); + /* * Wait for all pending hash_page to finish. This is needed * in case of subpage collapse. When we collapse normal pages diff --git a/arch/powerpc/mm/book3s64/pgtable.c b/arch/powerpc/mm/book3s64/pgtable.c index b4708b2cabba..3702d5bc7a5a 100644 --- a/arch/powerpc/mm/book3s64/pgtable.c +++ b/arch/powerpc/mm/book3s64/pgtable.c @@ -10,6 +10,7 @@ #include <linux/pkeys.h> #include <linux/debugfs.h> #include <linux/proc_fs.h> +#include <linux/page_table_check.h> #include <misc/cxl-base.h> #include <asm/pgalloc.h> @@ -129,6 +130,7 @@ void set_pmd_at(struct mm_struct *mm, unsigned long addr, WARN_ON(!(pmd_leaf(pmd))); #endif trace_hugepage_set_pmd(addr, pmd_val(pmd)); + page_table_check_pmd_set(mm, addr, pmdp, pmd); return set_pte_at_unchecked(mm, addr, pmdp_ptep(pmdp), pmd_pte(pmd)); } @@ -146,6 +148,7 @@ void set_pud_at(struct mm_struct *mm, unsigned long addr, WARN_ON(!(pud_leaf(pud))); #endif trace_hugepage_set_pud(addr, pud_val(pud)); + page_table_check_pud_set(mm, addr, pudp, pud); return set_pte_at_unchecked(mm, addr, pudp_ptep(pudp), pud_pte(pud)); } @@ -181,12 +184,14 @@ void serialize_against_pte_lookup(struct mm_struct *mm) pmd_t pmdp_invalidate(struct vm_area_struct *vma, unsigned long address, pmd_t *pmdp) { - unsigned long old_pmd; + pmd_t old_pmd; VM_WARN_ON_ONCE(!pmd_present(*pmdp)); - old_pmd = pmd_hugepage_update(vma->vm_mm, address, pmdp, _PAGE_PRESENT, _PAGE_INVALID); + old_pmd = __pmd(pmd_hugepage_update(vma->vm_mm, address, pmdp, _PAGE_PRESENT, _PAGE_INVALID)); flush_pmd_tlb_range(vma, address, address + HPAGE_PMD_SIZE); - return __pmd(old_pmd); + page_table_check_pmd_clear(vma->vm_mm, address, old_pmd); + + return old_pmd; } pud_t pudp_invalidate(struct vm_area_struct *vma, unsigned long address, diff --git a/arch/powerpc/mm/book3s64/radix_pgtable.c b/arch/powerpc/mm/book3s64/radix_pgtable.c index 1704381f5c3c..cc0dda11a640 100644 --- a/arch/powerpc/mm/book3s64/radix_pgtable.c +++ b/arch/powerpc/mm/book3s64/radix_pgtable.c @@ -14,6 +14,7 @@ #include <linux/of.h> #include <linux/of_fdt.h> #include <linux/mm.h> +#include <linux/page_table_check.h> #include <linux/hugetlb.h> #include <linux/string_helpers.h> #include <linux/memory.h> @@ -1454,6 +1455,8 @@ pmd_t radix__pmdp_collapse_flush(struct vm_area_struct *vma, unsigned long addre pmd = *pmdp; pmd_clear(pmdp); + page_table_check_pmd_clear(vma->vm_mm, address, pmd); + radix__flush_tlb_collapsed_pmd(vma->vm_mm, address); return pmd; diff --git a/arch/powerpc/mm/pgtable.c b/arch/powerpc/mm/pgtable.c index 4cc9af7961ca..ed46151ae1d9 100644 --- a/arch/powerpc/mm/pgtable.c +++ b/arch/powerpc/mm/pgtable.c @@ -22,6 +22,7 @@ #include <linux/mm.h> #include <linux/percpu.h> #include <linux/hardirq.h> +#include <linux/page_table_check.h> #include <linux/hugetlb.h> #include <asm/tlbflush.h> #include <asm/tlb.h> @@ -206,6 +207,9 @@ void set_ptes(struct mm_struct *mm, unsigned long addr, pte_t *ptep, * and not hw_valid ptes. Hence there is no translation cache flush * involved that need to be batched. */ + + page_table_check_ptes_set(mm, addr, ptep, pte, nr); + for (;;) { /* -- 2.48.1