Message ID | 20200610205153.2655528-2-cascardo@canonical.com |
---|---|
State | New |
Headers | show |
Series | [SRU,B/D/E/F] mm: Fix mremap not considering huge pmd devmap | expand |
On 10.06.20 22:51, Thadeu Lima de Souza Cascardo wrote: > From: Fan Yang <Fan_Yang@sjtu.edu.cn> > > The original code in mm/mremap.c checks huge pmd by: > > if (is_swap_pmd(*old_pmd) || pmd_trans_huge(*old_pmd)) { > > However, a DAX mapped nvdimm is mapped as huge page (by default) but it > is not transparent huge page (_PAGE_PSE | PAGE_DEVMAP). This commit > changes the condition to include the case. > > This addresses CVE-2020-10757. > > Fixes: 5c7fb56e5e3f ("mm, dax: dax-pmd vs thp-pmd vs hugetlbfs-pmd") > Cc: <stable@vger.kernel.org> > Reported-by: Fan Yang <Fan_Yang@sjtu.edu.cn> > Signed-off-by: Fan Yang <Fan_Yang@sjtu.edu.cn> > Tested-by: Fan Yang <Fan_Yang@sjtu.edu.cn> > Tested-by: Dan Williams <dan.j.williams@intel.com> > Reviewed-by: Dan Williams <dan.j.williams@intel.com> > Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> > Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> > (cherry picked from commit 5bfea2d9b17f1034a68147a8b03b9789af5700f9) > CVE-2020-10757 > Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com> Acked-by: Stefan Bader <stefan.bader@canonical.com> > --- > arch/x86/include/asm/pgtable.h | 1 + > mm/mremap.c | 2 +- > 2 files changed, 2 insertions(+), 1 deletion(-) > > diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h > index 1e6bb4c25334..ea85f23d9e22 100644 > --- a/arch/x86/include/asm/pgtable.h > +++ b/arch/x86/include/asm/pgtable.h > @@ -253,6 +253,7 @@ static inline int pmd_large(pmd_t pte) > } > > #ifdef CONFIG_TRANSPARENT_HUGEPAGE > +/* NOTE: when predicate huge page, consider also pmd_devmap, or use pmd_large */ > static inline int pmd_trans_huge(pmd_t pmd) > { > return (pmd_val(pmd) & (_PAGE_PSE|_PAGE_DEVMAP)) == _PAGE_PSE; > diff --git a/mm/mremap.c b/mm/mremap.c > index 245bf9c555b2..8005d0b2b843 100644 > --- a/mm/mremap.c > +++ b/mm/mremap.c > @@ -266,7 +266,7 @@ unsigned long move_page_tables(struct vm_area_struct *vma, > new_pmd = alloc_new_pmd(vma->vm_mm, vma, new_addr); > if (!new_pmd) > break; > - if (is_swap_pmd(*old_pmd) || pmd_trans_huge(*old_pmd)) { > + if (is_swap_pmd(*old_pmd) || pmd_trans_huge(*old_pmd) || pmd_devmap(*old_pmd)) { > if (extent == HPAGE_PMD_SIZE) { > bool moved; > /* See comment in move_ptes() */ >
Acked-by: Sultan Alsawaf <sultan.alsawaf@canonical.com> On Wed, Jun 10, 2020 at 05:51:53PM -0300, Thadeu Lima de Souza Cascardo wrote: > From: Fan Yang <Fan_Yang@sjtu.edu.cn> > > The original code in mm/mremap.c checks huge pmd by: > > if (is_swap_pmd(*old_pmd) || pmd_trans_huge(*old_pmd)) { > > However, a DAX mapped nvdimm is mapped as huge page (by default) but it > is not transparent huge page (_PAGE_PSE | PAGE_DEVMAP). This commit > changes the condition to include the case. > > This addresses CVE-2020-10757. > > Fixes: 5c7fb56e5e3f ("mm, dax: dax-pmd vs thp-pmd vs hugetlbfs-pmd") > Cc: <stable@vger.kernel.org> > Reported-by: Fan Yang <Fan_Yang@sjtu.edu.cn> > Signed-off-by: Fan Yang <Fan_Yang@sjtu.edu.cn> > Tested-by: Fan Yang <Fan_Yang@sjtu.edu.cn> > Tested-by: Dan Williams <dan.j.williams@intel.com> > Reviewed-by: Dan Williams <dan.j.williams@intel.com> > Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> > Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> > (cherry picked from commit 5bfea2d9b17f1034a68147a8b03b9789af5700f9) > CVE-2020-10757 > Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com> > --- > arch/x86/include/asm/pgtable.h | 1 + > mm/mremap.c | 2 +- > 2 files changed, 2 insertions(+), 1 deletion(-) > > diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h > index 1e6bb4c25334..ea85f23d9e22 100644 > --- a/arch/x86/include/asm/pgtable.h > +++ b/arch/x86/include/asm/pgtable.h > @@ -253,6 +253,7 @@ static inline int pmd_large(pmd_t pte) > } > > #ifdef CONFIG_TRANSPARENT_HUGEPAGE > +/* NOTE: when predicate huge page, consider also pmd_devmap, or use pmd_large */ > static inline int pmd_trans_huge(pmd_t pmd) > { > return (pmd_val(pmd) & (_PAGE_PSE|_PAGE_DEVMAP)) == _PAGE_PSE; > diff --git a/mm/mremap.c b/mm/mremap.c > index 245bf9c555b2..8005d0b2b843 100644 > --- a/mm/mremap.c > +++ b/mm/mremap.c > @@ -266,7 +266,7 @@ unsigned long move_page_tables(struct vm_area_struct *vma, > new_pmd = alloc_new_pmd(vma->vm_mm, vma, new_addr); > if (!new_pmd) > break; > - if (is_swap_pmd(*old_pmd) || pmd_trans_huge(*old_pmd)) { > + if (is_swap_pmd(*old_pmd) || pmd_trans_huge(*old_pmd) || pmd_devmap(*old_pmd)) { > if (extent == HPAGE_PMD_SIZE) { > bool moved; > /* See comment in move_ptes() */ > -- > 2.25.1 > > > -- > kernel-team mailing list > kernel-team@lists.ubuntu.com > https://lists.ubuntu.com/mailman/listinfo/kernel-team
diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h index 1e6bb4c25334..ea85f23d9e22 100644 --- a/arch/x86/include/asm/pgtable.h +++ b/arch/x86/include/asm/pgtable.h @@ -253,6 +253,7 @@ static inline int pmd_large(pmd_t pte) } #ifdef CONFIG_TRANSPARENT_HUGEPAGE +/* NOTE: when predicate huge page, consider also pmd_devmap, or use pmd_large */ static inline int pmd_trans_huge(pmd_t pmd) { return (pmd_val(pmd) & (_PAGE_PSE|_PAGE_DEVMAP)) == _PAGE_PSE; diff --git a/mm/mremap.c b/mm/mremap.c index 245bf9c555b2..8005d0b2b843 100644 --- a/mm/mremap.c +++ b/mm/mremap.c @@ -266,7 +266,7 @@ unsigned long move_page_tables(struct vm_area_struct *vma, new_pmd = alloc_new_pmd(vma->vm_mm, vma, new_addr); if (!new_pmd) break; - if (is_swap_pmd(*old_pmd) || pmd_trans_huge(*old_pmd)) { + if (is_swap_pmd(*old_pmd) || pmd_trans_huge(*old_pmd) || pmd_devmap(*old_pmd)) { if (extent == HPAGE_PMD_SIZE) { bool moved; /* See comment in move_ptes() */