From 3f0eb66f652ceb5985b9b619e33fc61519121045 Mon Sep 17 00:00:00 2001 From: Michal Hocko Date: Wed, 27 Jun 2018 17:46:50 +0200 Subject: [PATCH] x86/speculation/l1tf: Fix up pte->pfn conversion for PAE commit e14d7dfb41f5807a0c1c26a13f2b8ef16af24935 upstream Jan has noticed that pte_pfn and co. resp. pfn_pte are incorrect for CONFIG_PAE because phys_addr_t is wider than unsigned long and so the pte_val reps. shift left would get truncated. Fix this up by using proper types. [dwmw2: Backport to 4.9] Fixes: 6b28baca9b1f ("x86/speculation/l1tf: Protect PROT_NONE PTEs against speculation") Reported-by: Jan Beulich Signed-off-by: Michal Hocko Signed-off-by: Thomas Gleixner Acked-by: Vlastimil Babka Signed-off-by: David Woodhouse Signed-off-by: Greg Kroah-Hartman --- arch/x86/include/asm/pgtable.h | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h index 38b679df..4e06358 100644 --- a/arch/x86/include/asm/pgtable.h +++ b/arch/x86/include/asm/pgtable.h @@ -171,21 +171,21 @@ static inline u64 protnone_mask(u64 val); static inline unsigned long pte_pfn(pte_t pte) { - unsigned long pfn = pte_val(pte); + phys_addr_t pfn = pte_val(pte); pfn ^= protnone_mask(pfn); return (pfn & PTE_PFN_MASK) >> PAGE_SHIFT; } static inline unsigned long pmd_pfn(pmd_t pmd) { - unsigned long pfn = pmd_val(pmd); + phys_addr_t pfn = pmd_val(pmd); pfn ^= protnone_mask(pfn); return (pfn & pmd_pfn_mask(pmd)) >> PAGE_SHIFT; } static inline unsigned long pud_pfn(pud_t pud) { - unsigned long pfn = pud_val(pud); + phys_addr_t pfn = pud_val(pud); pfn ^= protnone_mask(pfn); return (pfn & pud_pfn_mask(pud)) >> PAGE_SHIFT; } @@ -404,7 +404,7 @@ static inline pgprotval_t massage_pgprot(pgprot_t pgprot) static inline pte_t pfn_pte(unsigned long page_nr, pgprot_t pgprot) { - phys_addr_t pfn = page_nr << PAGE_SHIFT; + phys_addr_t pfn = (phys_addr_t)page_nr << PAGE_SHIFT; pfn ^= protnone_mask(pgprot_val(pgprot)); pfn &= PTE_PFN_MASK; return __pte(pfn | massage_pgprot(pgprot)); @@ -412,7 +412,7 @@ static inline pte_t pfn_pte(unsigned long page_nr, pgprot_t pgprot) static inline pmd_t pfn_pmd(unsigned long page_nr, pgprot_t pgprot) { - phys_addr_t pfn = page_nr << PAGE_SHIFT; + phys_addr_t pfn = (phys_addr_t)page_nr << PAGE_SHIFT; pfn ^= protnone_mask(pgprot_val(pgprot)); pfn &= PHYSICAL_PMD_PAGE_MASK; return __pmd(pfn | massage_pgprot(pgprot)); -- 2.7.4