David Hildenbrand afeb0e6962 drivers/virt/acrn: fix PFNMAP PTE checks in acrn_vm_ram_map() ... [ Upstream commit 3d6586008f ] Patch series "mm: follow_pte() improvements and acrn follow_pte() fixes". Patch #1 fixes a bunch of issues I spotted in the acrn driver. It compiles, that's all I know. I'll appreciate some review and testing from acrn folks. Patch #2+#3 improve follow_pte(), passing a VMA instead of the MM, adding more sanity checks, and improving the documentation. Gave it a quick test on x86-64 using VM_PAT that ends up using follow_pte(). This patch (of 3): We currently miss handling various cases, resulting in a dangerous follow_pte() (previously follow_pfn()) usage. (1) We're not checking PTE write permissions. Maybe we should simply always require pte_write() like we do for pin_user_pages_fast(FOLL_WRITE)? Hard to tell, so let's check for ACRN_MEM_ACCESS_WRITE for now. (2) We're not rejecting refcounted pages. As we are not using MMU notifiers, messing with refcounted pages is dangerous and can result in use-after-free. Let's make sure to reject them. (3) We are only looking at the first PTE of a bigger range. We only lookup a single PTE, but memmap->len may span a larger area. Let's loop over all involved PTEs and make sure the PFN range is actually contiguous. Reject everything else: it couldn't have worked either way, and rather made use access PFNs we shouldn't be accessing. Link: https://lkml.kernel.org/r/20240410155527.474777-1-david@redhat.com Link: https://lkml.kernel.org/r/20240410155527.474777-2-david@redhat.com Fixes: 8a6e85f75a ("virt: acrn: obtain pa from VMA with PFNMAP flag") Signed-off-by: David Hildenbrand <david@redhat.com> Cc: Alex Williamson <alex.williamson@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Fei Li <fei1.li@intel.com> Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Yonghua Huang <yonghua.huang@intel.com> Cc: Sean Christopherson <seanjc@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>		2024-06-12 11:03:30 +02:00
..
acrn	drivers/virt/acrn: fix PFNMAP PTE checks in acrn_vm_ram_map()	2024-06-12 11:03:30 +02:00
coco	virt: sevguest: Fix passing a stack buffer as a scatterlist target	2023-11-20 11:52:13 +01:00
nitro_enclaves	kunit: fix Kconfig for build-in tests USB4 and Nitro Enclaves	2022-09-01 13:00:48 -06:00
vboxguest	virt: vbox: Remove unproper information	2022-09-09 10:19:18 +02:00
fsl_hypervisor.c	drivers/virt/fsl_hypervisor: remove unneeded ret variable in fsl_hv_open()	2022-04-26 12:50:31 +02:00
Kconfig	AMD SEV-SNP support	2022-05-23 17:38:01 -07:00
Makefile	AMD SEV-SNP support	2022-05-23 17:38:01 -07:00
vmgenid.c	virt: vmgenid: recognize new CID added by Hyper-V	2022-03-25 08:49:40 -06:00