From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0464C1E2858; Thu, 18 Jun 2026 18:32:38 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781807560; cv=none; b=tBDarlxTsypY0f8gS40PqhlidNVQshQ0uqnuBBv1sWTPS4Ks5ABqzUFRBn9L1eeFSt0AGP4pL31OwjYRt4UqfrpaBLoNr/wPTOijbUsfkUjs0MuUn0+gUXFCh4ZRzJ+Dp+6e3CUGLBs57q0F1fOQ+aSnlbFum4eOgIvqeguxgvY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781807560; c=relaxed/simple; bh=SuhuIe7N9+7TnWTYM917xX9rZBIi9jVGRbQNq5PTSNY=; h=Date:To:From:Subject:Message-Id; b=Dc7MCNQKtwVDibI4myatzpbRMDJ4ndPwt6bJPIPJ1geoHwCAX2byFdNe/inZs9W1cTI7mlfcU+AsShQChddloVt3V2htcfnSSGNVSZvl/slpxGSD8RgixoKO2J/gJArkmcvORRTUlLC1/Rd+WGXrpwDtjhrHN9lNwqgzkTKV47s= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=bTj9tApY; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="bTj9tApY" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 982EB1F000E9; Thu, 18 Jun 2026 18:32:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=korg; t=1781807558; bh=AhsxZj7C4tAqawIpQ8x+qjLg67U3dX/bTZyEp0Lquqg=; h=Date:To:From:Subject; b=bTj9tApYUywqftgN/MLlvwyDpx73qrggfyjoe54dU4ACGJVSKZZNWUr46ETDYc2dn 0JOqCIH0D6SsxFpHLMj1xQZx2Jj0JIwuXoIY5uxzy74Aw4XmYAP2ZYemJLHplfA6Jo j72FkSVG2k2VJGGWj6Qo+/8smilFFAG7DPrcRYNM= Date: Thu, 18 Jun 2026 11:32:37 -0700 To: mm-commits@vger.kernel.org,vladimirelitokarev@gmail.com,viro@zeniv.linux.org.uk,torvalds@linuxfoundation.org,stable@vger.kernel.org,peterx@redhat.com,oleg@redhat.com,jack@suse.cz,david@kernel.org,brauner@kernel.org,rppt@kernel.org,akpm@linux-foundation.org From: Andrew Morton Subject: [to-be-updated] userfaultfd-prevent-registration-of-special-vmas.patch removed from -mm tree Message-Id: <20260618183238.982EB1F000E9@smtp.kernel.org> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: The quilt patch titled Subject: userfaultfd: prevent registration of special VMAs has been removed from the -mm tree. Its filename was userfaultfd-prevent-registration-of-special-vmas.patch This patch was dropped because an updated version will be issued ------------------------------------------------------ From: "Mike Rapoport (Microsoft)" Subject: userfaultfd: prevent registration of special VMAs Date: Wed, 17 Jun 2026 22:40:59 +0300 Vova Tokarev says: userfaultfd allows registration on shadow stack VMAs. With userfaultfd access, you can register on the shadow stack, discard a page ... and inject a page with chosen return addresses via UFFDIO_COPY. Update vma_can_userfault() to reject VM_SHADOW_STACK. While on it, also reject VM_IO, VM_MIXEDMAP and VM_PFNMAP so that if a driver would implement vm_uffd_ops, it wouldn't be possible to register special VMAs with userfaultfd. Link: https://lore.kernel.org/20260617194059.2529406-1-rppt@kernel.org Fixes: 54007f818206 ("mm: Introduce VM_SHADOW_STACK for shadow stack memory") Reported-by: vova tokarev Signed-off-by: Mike Rapoport (Microsoft) Cc: Al Viro Cc: Christian Brauner Cc: David Hildenbrand Cc: Jan Kara Cc: Linus Torvalds Cc: Oleg Nesterov Cc: Peter Xu Cc: Signed-off-by: Andrew Morton --- mm/userfaultfd.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/mm/userfaultfd.c~userfaultfd-prevent-registration-of-special-vmas +++ a/mm/userfaultfd.c @@ -2095,7 +2095,8 @@ bool vma_can_userfault(struct vm_area_st { const struct vm_uffd_ops *ops = vma_uffd_ops(vma); - if (vma->vm_flags & VM_DROPPABLE) + if (vma->vm_flags & (VM_DROPPABLE | VM_IO | VM_MIXEDMAP | VM_PFNMAP | + VM_SHADOW_STACK)) return false; vm_flags &= __VM_UFFD_FLAGS; _ Patches currently in -mm which might be from rppt@kernel.org are selftests-mm-hugetlb-read-hwpoison-add-sigbus-handler.patch selftests-mm-migration-dont-assume-huge-page-is-twomeg.patch selftests-mm-migration-make-nthreads-represent-number-of-working-threads.patch selftests-mm-migration-properly-cleanup-forked-processes.patch selftests-mm-run_vmtestssh-dont-gate-thp-and-ksm-tests-on-have_hugepages.patch selftests-mm-merge-map_hugetlb-into-hugepage-mmap.patch selftests-mm-rename-hugepage-tests-to-hugetlb.patch selftests-mm-hugetlb-shm-use-kselftest-framework.patch selftests-mm-hugetlb-vmemmap-use-kselftest-framework.patch selftests-mm-hugetlb-madvise-use-kselftest-framework.patch selftests-mm-hugetlb_madv_vs_map-use-kselftest-framework.patch selftests-mm-hugetlb-read-hwpoison-use-kselftest-framework.patch selftests-mm-khugepaged-group-tests-in-an-array.patch selftests-mm-khugepaged-use-ksefltest-framework.patch selftests-mm-ksm_tests-use-kselftest-framework.patch selftests-mm-protection_keys-use-descriptive-test-names-in-the-output.patch selftests-mm-protection_keys-use-kselftest-framework.patch selftests-mm-uffd-common-use-kselftest-framework.patch selftests-mm-uffd-stress-use-kselftest-framework.patch selftests-mm-uffd-unit-tests-use-kselftest-framework.patch selftests-mm-va_high_addr_switch-use-kselftest-framework.patch selftests-mm-add-atexit-and-signal-handlers-to-thp_settings.patch selftests-mm-rename-thp_settings-to-hugepage_settings.patch selftests-mm-move-hugetlb-helpers-to-hugepage_settings.patch selftests-mm-hugepage_settings-use-unsigned-long-in-detect_hugetlb_page_size.patch selftests-mm-hugepage_settings-add-apis-to-get-and-set-nr_hugepages.patch selftests-mm-hugepage_settings-rename-and-rework-get_free_hugepages.patch selftests-mm-hugepage_settings-add-apis-for-hugetlb-setup-and-teardown.patch selftests-mm-move-read_file-read_num-and-write_num-to-vm_util.patch selftests-mm-vm_util-add-helpers-to-set-and-restore-shm-limits.patch selftests-mm-compaction_test-use-hugetlb-helpers.patch selftests-mm-cow-add-setup-of-hugetlb-pages.patch selftests-mm-gup_longterm-add-setup-of-hugetlb-pages.patch selftests-mm-gup_test-add-setup-of-hugetlb-pages.patch selftests-mm-hmm-tests-add-setup-of-hugetlb-pages.patch selftests-mm-hugepage_dio-add-setup-of-hugetlb-pages.patch selftests-mm-hugetlb_fault_after_madv-add-setup-of-hugetlb-pages.patch selftests-mm-hugetlb-madvise-add-setup-of-hugetlb-pages.patch selftests-mm-hugetlb_madv_vs_map-add-setup-of-hugetlb-pages.patch selftests-mm-hugetlb-mmap-add-setup-of-hugetlb-pages.patch selftests-mm-hugetlb-mremap-add-setup-of-hugetlb-pages.patch selftests-mm-hugetlb-shm-add-setup-of-hugetlb-pages.patch selftests-mm-hugetlb-soft-offline-add-setup-of-hugetlb-pages.patch selftests-mm-hugetlb-vmemmap-add-setup-of-hugetlb-pages.patch selftests-mm-migration-add-setup-of-hugetlb-pages.patch selftests-mm-pagemap_ioctl-add-setup-of-hugetlb-pages.patch selftests-mm-protection_keys-use-library-code-for-hugetlb-setup.patch selftests-mm-thuge-gen-add-setup-of-hugetlb-pages.patch selftests-mm-uffd-stress-use-hugetlb_save-and-alloc-huge-pages.patch selftests-mm-uffd-unit-tests-add-setup-of-hugetlb-pages.patch selftests-mm-uffd-wp-mremap-add-setup-of-hugetlb-pages.patch selftests-mm-va_high_addr_switch-add-setup-of-hugetlb-pages.patch selftests-mm-va_high_addr_switchsh-drop-huge-pages-setup.patch selftests-mm-run_vmtestssh-free-memory-if-available-memory-is-low.patch selftests-mm-run_vmtestssh-drop-detection-and-setup-of-hugetlb.patch