From mboxrd@z Thu Jan 1 00:00:00 1970 From: Yu-cheng Yu Subject: [PATCH v10 15/26] mm: Fixup places that call pte_mkwrite() directly Date: Wed, 29 Apr 2020 15:07:21 -0700 Message-ID: <20200429220732.31602-16-yu-cheng.yu@intel.com> References: <20200429220732.31602-1-yu-cheng.yu@intel.com> Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <20200429220732.31602-1-yu-cheng.yu@intel.com> Sender: linux-kernel-owner@vger.kernel.org To: x86@kernel.org, "H. Peter Anvin" , Thomas Gleixner , Ingo Molnar , linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linux-mm@kvack.org, linux-arch@vger.kernel.org, linux-api@vger.kernel.org, Arnd Bergmann , Andy Lutomirski , Balbir Singh , Borislav Petkov , Cyrill Gorcunov , Dave Hansen , Eugene Syromiatnikov , Florian Weimer , "H.J. Lu" , Jann Horn , Jonathan Corbet , Kees Cook , Mike Kravetz , Nadav Amit Cc: Yu-cheng Yu List-Id: linux-arch.vger.kernel.org A shadow stack page is made writable by pte_mkwrite_shstk(), which sets _PAGE_DIRTY_HW. There are a few places that call pte_mkwrite() directly and miss the maybe_mkwrite() fixup in the previous patch. Fix them with maybe_mkwrite(): - do_anonymous_page() and migrate_vma_insert_page() check VM_WRITE directly and call pte_mkwrite(), which is the same as maybe_mkwrite(). Change them to maybe_mkwrite(). - In do_numa_page(), if the numa entry 'was-writable', then pte_mkwrite() is called directly. Fix it by doing maybe_mkwrite(). - In change_pte_range(), pte_mkwrite() is called directly. Replace it with maybe_mkwrite(). Signed-off-by: Yu-cheng Yu --- mm/memory.c | 5 ++--- mm/migrate.c | 3 +-- mm/mprotect.c | 2 +- 3 files changed, 4 insertions(+), 6 deletions(-) diff --git a/mm/memory.c b/mm/memory.c index f703fe8c8346..b9002f644806 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -3373,8 +3373,7 @@ static vm_fault_t do_anonymous_page(struct vm_fault *vmf) __SetPageUptodate(page); entry = mk_pte(page, vma->vm_page_prot); - if (vma->vm_flags & VM_WRITE) - entry = pte_mkwrite(pte_mkdirty(entry)); + entry = maybe_mkwrite(pte_mkdirty(entry), vma); vmf->pte = pte_offset_map_lock(vma->vm_mm, vmf->pmd, vmf->address, &vmf->ptl); @@ -4033,7 +4032,7 @@ static vm_fault_t do_numa_page(struct vm_fault *vmf) pte = pte_modify(old_pte, vma->vm_page_prot); pte = pte_mkyoung(pte); if (was_writable) - pte = pte_mkwrite(pte); + pte = maybe_mkwrite(pte, vma); ptep_modify_prot_commit(vma, vmf->address, vmf->pte, old_pte, pte); update_mmu_cache(vma, vmf->address, vmf->pte); diff --git a/mm/migrate.c b/mm/migrate.c index 7160c1556f79..0fa59b1562c6 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -2805,8 +2805,7 @@ static void migrate_vma_insert_page(struct migrate_vma *migrate, } } else { entry = mk_pte(page, vma->vm_page_prot); - if (vma->vm_flags & VM_WRITE) - entry = pte_mkwrite(pte_mkdirty(entry)); + entry = maybe_mkwrite(pte_mkdirty(entry), vma); } ptep = pte_offset_map_lock(mm, pmdp, addr, &ptl); diff --git a/mm/mprotect.c b/mm/mprotect.c index 494192ca954b..02762af1057c 100644 --- a/mm/mprotect.c +++ b/mm/mprotect.c @@ -135,7 +135,7 @@ static unsigned long change_pte_range(struct vm_area_struct *vma, pmd_t *pmd, if (dirty_accountable && pte_dirty(ptent) && (pte_soft_dirty(ptent) || !(vma->vm_flags & VM_SOFTDIRTY))) { - ptent = pte_mkwrite(ptent); + ptent = maybe_mkwrite(ptent, vma); } ptep_modify_prot_commit(vma, addr, pte, oldpte, ptent); pages++; -- 2.21.0 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Yu-cheng Yu Subject: [PATCH v10 15/26] mm: Fixup places that call pte_mkwrite() directly Date: Wed, 29 Apr 2020 15:07:21 -0700 Message-ID: <20200429220732.31602-16-yu-cheng.yu@intel.com> In-Reply-To: <20200429220732.31602-1-yu-cheng.yu@intel.com> References: <20200429220732.31602-1-yu-cheng.yu@intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Sender: owner-linux-mm@kvack.org To: x86@kernel.org, "H. Peter Anvin" , Thomas Gleixner , Ingo Molnar , linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linux-mm@kvack.org, linux-arch@vger.kernel.org, linux-api@vger.kernel.org, Arnd Bergmann , Andy Lutomirski , Balbir Singh , Borislav Petkov , Cyrill Gorcunov , Dave Hansen , Eugene Syromiatnikov , Florian Weimer , "H.J. Lu" , Jann Horn , Jonathan Corbet , Kees Cook , Mike Kravetz , Nadav Amit , Oleg Nesterov , Pavel Machek , Peter Zijlstra , Randy Dunlap , "Ravi V. Shankar" , Vedvyas Shanbhogue , Dave Martin , Weijiang Yang Cc: Yu-cheng Yu List-ID: Message-ID: <20200429220721.2XRqk7h3GPgst8O1Ck1QulPgnr59dSqt7qS-r6KKTts@z> A shadow stack page is made writable by pte_mkwrite_shstk(), which sets _PAGE_DIRTY_HW. There are a few places that call pte_mkwrite() directly and miss the maybe_mkwrite() fixup in the previous patch. Fix them with maybe_mkwrite(): - do_anonymous_page() and migrate_vma_insert_page() check VM_WRITE direct= ly and call pte_mkwrite(), which is the same as maybe_mkwrite(). Change them to maybe_mkwrite(). - In do_numa_page(), if the numa entry 'was-writable', then pte_mkwrite() is called directly. Fix it by doing maybe_mkwrite(). - In change_pte_range(), pte_mkwrite() is called directly. Replace it wi= th maybe_mkwrite(). Signed-off-by: Yu-cheng Yu --- mm/memory.c | 5 ++--- mm/migrate.c | 3 +-- mm/mprotect.c | 2 +- 3 files changed, 4 insertions(+), 6 deletions(-) diff --git a/mm/memory.c b/mm/memory.c index f703fe8c8346..b9002f644806 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -3373,8 +3373,7 @@ static vm_fault_t do_anonymous_page(struct vm_fault= *vmf) __SetPageUptodate(page); =20 entry =3D mk_pte(page, vma->vm_page_prot); - if (vma->vm_flags & VM_WRITE) - entry =3D pte_mkwrite(pte_mkdirty(entry)); + entry =3D maybe_mkwrite(pte_mkdirty(entry), vma); =20 vmf->pte =3D pte_offset_map_lock(vma->vm_mm, vmf->pmd, vmf->address, &vmf->ptl); @@ -4033,7 +4032,7 @@ static vm_fault_t do_numa_page(struct vm_fault *vmf= ) pte =3D pte_modify(old_pte, vma->vm_page_prot); pte =3D pte_mkyoung(pte); if (was_writable) - pte =3D pte_mkwrite(pte); + pte =3D maybe_mkwrite(pte, vma); ptep_modify_prot_commit(vma, vmf->address, vmf->pte, old_pte, pte); update_mmu_cache(vma, vmf->address, vmf->pte); =20 diff --git a/mm/migrate.c b/mm/migrate.c index 7160c1556f79..0fa59b1562c6 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -2805,8 +2805,7 @@ static void migrate_vma_insert_page(struct migrate_= vma *migrate, } } else { entry =3D mk_pte(page, vma->vm_page_prot); - if (vma->vm_flags & VM_WRITE) - entry =3D pte_mkwrite(pte_mkdirty(entry)); + entry =3D maybe_mkwrite(pte_mkdirty(entry), vma); } =20 ptep =3D pte_offset_map_lock(mm, pmdp, addr, &ptl); diff --git a/mm/mprotect.c b/mm/mprotect.c index 494192ca954b..02762af1057c 100644 --- a/mm/mprotect.c +++ b/mm/mprotect.c @@ -135,7 +135,7 @@ static unsigned long change_pte_range(struct vm_area_= struct *vma, pmd_t *pmd, if (dirty_accountable && pte_dirty(ptent) && (pte_soft_dirty(ptent) || !(vma->vm_flags & VM_SOFTDIRTY))) { - ptent =3D pte_mkwrite(ptent); + ptent =3D maybe_mkwrite(ptent, vma); } ptep_modify_prot_commit(vma, addr, pte, oldpte, ptent); pages++; --=20 2.21.0