From 1c399e74a97ca733d0780cc51819aa81fb292c22 Mon Sep 17 00:00:00 2001 From: Peter Xu Date: Mon, 12 Aug 2024 14:12:23 -0400 Subject: mm/x86: implement arch_check_zapped_pud() Introduce arch_check_zapped_pud() to sanity check shadow stack on PUD zaps. It has the same logic as the PMD helper. One thing to mention is, it might be a good idea to use page_table_check in the future for trapping wrong setups of shadow stack pgtable entries [1]. That is left for the future as a separate effort. [1] https://lore.kernel.org/all/59d518698f664e07c036a5098833d7b56b953305.camel@intel.com Link: https://lkml.kernel.org/r/20240812181225.1360970-6-peterx@redhat.com Signed-off-by: Peter Xu Acked-by: David Hildenbrand Cc: "Edgecombe, Rick P" Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Borislav Petkov Cc: Dave Hansen Cc: Aneesh Kumar K.V Cc: Christophe Leroy Cc: Dan Williams Cc: Dave Jiang Cc: David Rientjes Cc: Hugh Dickins Cc: Kirill A. Shutemov Cc: Matthew Wilcox Cc: Michael Ellerman Cc: Nicholas Piggin Cc: Oscar Salvador Cc: Paolo Bonzini Cc: Rik van Riel Cc: Sean Christopherson Cc: Vlastimil Babka Signed-off-by: Andrew Morton --- include/linux/pgtable.h | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'include/linux/pgtable.h') diff --git a/include/linux/pgtable.h b/include/linux/pgtable.h index 2a6a3cccfc36..780f3b439d98 100644 --- a/include/linux/pgtable.h +++ b/include/linux/pgtable.h @@ -447,6 +447,12 @@ static inline void arch_check_zapped_pmd(struct vm_area_struct *vma, } #endif +#ifndef arch_check_zapped_pud +static inline void arch_check_zapped_pud(struct vm_area_struct *vma, pud_t pud) +{ +} +#endif + #ifndef __HAVE_ARCH_PTEP_GET_AND_CLEAR static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long address, -- cgit v1.2.3 From 0515e022e167cfacf1fee092eb93aa9514e23c0a Mon Sep 17 00:00:00 2001 From: Peter Xu Date: Mon, 26 Aug 2024 16:43:42 -0400 Subject: mm: always define pxx_pgprot() There're: - 8 archs (arc, arm64, include, mips, powerpc, s390, sh, x86) that support pte_pgprot(). - 2 archs (x86, sparc) that support pmd_pgprot(). - 1 arch (x86) that support pud_pgprot(). Always define them to be used in generic code, and then we don't need to fiddle with "#ifdef"s when doing so. Link: https://lkml.kernel.org/r/20240826204353.2228736-9-peterx@redhat.com Signed-off-by: Peter Xu Reviewed-by: Jason Gunthorpe Cc: Alexander Gordeev Cc: Alex Williamson Cc: Aneesh Kumar K.V Cc: Borislav Petkov Cc: Catalin Marinas Cc: Christian Borntraeger Cc: Dave Hansen Cc: David Hildenbrand Cc: Gavin Shan Cc: Gerald Schaefer Cc: Heiko Carstens Cc: Ingo Molnar Cc: Matthew Wilcox Cc: Niklas Schnelle Cc: Paolo Bonzini Cc: Ryan Roberts Cc: Sean Christopherson Cc: Sven Schnelle Cc: Thomas Gleixner Cc: Vasily Gorbik Cc: Will Deacon Cc: Zi Yan Signed-off-by: Andrew Morton --- arch/arm64/include/asm/pgtable.h | 1 + arch/powerpc/include/asm/pgtable.h | 1 + arch/s390/include/asm/pgtable.h | 1 + arch/sparc/include/asm/pgtable_64.h | 1 + include/linux/pgtable.h | 12 ++++++++++++ 5 files changed, 16 insertions(+) (limited to 'include/linux/pgtable.h') diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h index 7a4f5604be3f..b78cc4a6758b 100644 --- a/arch/arm64/include/asm/pgtable.h +++ b/arch/arm64/include/asm/pgtable.h @@ -384,6 +384,7 @@ static inline void __sync_cache_and_tags(pte_t pte, unsigned int nr_pages) /* * Select all bits except the pfn */ +#define pte_pgprot pte_pgprot static inline pgprot_t pte_pgprot(pte_t pte) { unsigned long pfn = pte_pfn(pte); diff --git a/arch/powerpc/include/asm/pgtable.h b/arch/powerpc/include/asm/pgtable.h index 264a6c09517a..2f72ad885332 100644 --- a/arch/powerpc/include/asm/pgtable.h +++ b/arch/powerpc/include/asm/pgtable.h @@ -65,6 +65,7 @@ static inline unsigned long pte_pfn(pte_t pte) /* * Select all bits except the pfn */ +#define pte_pgprot pte_pgprot static inline pgprot_t pte_pgprot(pte_t pte) { unsigned long pte_flags; diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h index 3fa280d0672a..0ffbaf741955 100644 --- a/arch/s390/include/asm/pgtable.h +++ b/arch/s390/include/asm/pgtable.h @@ -955,6 +955,7 @@ static inline int pte_unused(pte_t pte) * young/old accounting is not supported, i.e _PAGE_PROTECT and _PAGE_INVALID * must not be set. */ +#define pte_pgprot pte_pgprot static inline pgprot_t pte_pgprot(pte_t pte) { unsigned long pte_flags = pte_val(pte) & _PAGE_CHG_MASK; diff --git a/arch/sparc/include/asm/pgtable_64.h b/arch/sparc/include/asm/pgtable_64.h index 3fe429d73a65..2b7f358762c1 100644 --- a/arch/sparc/include/asm/pgtable_64.h +++ b/arch/sparc/include/asm/pgtable_64.h @@ -783,6 +783,7 @@ static inline pmd_t pmd_mkwrite_novma(pmd_t pmd) return __pmd(pte_val(pte)); } +#define pmd_pgprot pmd_pgprot static inline pgprot_t pmd_pgprot(pmd_t entry) { unsigned long val = pmd_val(entry); diff --git a/include/linux/pgtable.h b/include/linux/pgtable.h index 780f3b439d98..e8b2ac6bd2ae 100644 --- a/include/linux/pgtable.h +++ b/include/linux/pgtable.h @@ -1956,6 +1956,18 @@ typedef unsigned int pgtbl_mod_mask; #define MAX_PTRS_PER_P4D PTRS_PER_P4D #endif +#ifndef pte_pgprot +#define pte_pgprot(x) ((pgprot_t) {0}) +#endif + +#ifndef pmd_pgprot +#define pmd_pgprot(x) ((pgprot_t) {0}) +#endif + +#ifndef pud_pgprot +#define pud_pgprot(x) ((pgprot_t) {0}) +#endif + /* description of effects of mapping type and prot in current implementation. * this is due to the limited x86 page protection hardware. The expected * behavior is in parens: -- cgit v1.2.3