This is a note to let you know that I've just added the patch titled [PATCH BACKPORT 3.10-3.15 2/4] MIPS: KVM: Add missing gfn range check to the 3.14-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: mips-kvm-add-missing-gfn-range-check.patch and it can be found in the queue-3.14 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From james.hogan@xxxxxxxxxx Thu Aug 18 11:46:20 2016 From: James Hogan <james.hogan@xxxxxxxxxx> Date: Thu, 18 Aug 2016 10:22:53 +0100 Subject: [PATCH BACKPORT 3.10-3.15 2/4] MIPS: KVM: Add missing gfn range check To: <stable@xxxxxxxxxxxxxxx> Cc: James Hogan <james.hogan@xxxxxxxxxx>, Paolo Bonzini <pbonzini@xxxxxxxxxx>, Radim Krčmář <rkrcmar@xxxxxxxxxx>, Ralf Baechle <ralf@xxxxxxxxxxxxxx>, <linux-mips@xxxxxxxxxxxxxx>, <kvm@xxxxxxxxxxxxxxx> Message-ID: <54b01d37d3ac6ff18fdef80d1189d3c1285d4f46.1471021142.git-series.james.hogan@xxxxxxxxxx> From: James Hogan <james.hogan@xxxxxxxxxx> commit 8985d50382359e5bf118fdbefc859d0dbf6cebc7 upstream. kvm_mips_handle_mapped_seg_tlb_fault() calculates the guest frame number based on the guest TLB EntryLo values, however it is not range checked to ensure it lies within the guest_pmap. If the physical memory the guest refers to is out of range then dump the guest TLB and emit an internal error. Fixes: 858dd5d45733 ("KVM/MIPS32: MMU/TLB operations for the Guest.") Signed-off-by: James Hogan <james.hogan@xxxxxxxxxx> Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx> Cc: "Radim Krčmář" <rkrcmar@xxxxxxxxxx> Cc: Ralf Baechle <ralf@xxxxxxxxxxxxxx> Cc: linux-mips@xxxxxxxxxxxxxx Cc: kvm@xxxxxxxxxxxxxxx Signed-off-by: Radim Krčmář <rkrcmar@xxxxxxxxxx> [james.hogan@xxxxxxxxxx: Backport to v3.10.y - v3.15.y] Signed-off-by: James Hogan <james.hogan@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/mips/kvm/kvm_tlb.c | 19 +++++++++++++++---- 1 file changed, 15 insertions(+), 4 deletions(-) --- a/arch/mips/kvm/kvm_tlb.c +++ b/arch/mips/kvm/kvm_tlb.c @@ -370,6 +370,7 @@ kvm_mips_handle_mapped_seg_tlb_fault(str unsigned long entryhi = 0, entrylo0 = 0, entrylo1 = 0; struct kvm *kvm = vcpu->kvm; pfn_t pfn0, pfn1; + gfn_t gfn0, gfn1; long tlb_lo[2]; tlb_lo[0] = tlb->tlb_lo0; @@ -383,14 +384,24 @@ kvm_mips_handle_mapped_seg_tlb_fault(str VPN2_MASK & (PAGE_MASK << 1))) tlb_lo[(KVM_GUEST_COMMPAGE_ADDR >> PAGE_SHIFT) & 1] = 0; - if (kvm_mips_map_page(kvm, mips3_tlbpfn_to_paddr(tlb_lo[0]) >> PAGE_SHIFT) < 0) + gfn0 = mips3_tlbpfn_to_paddr(tlb_lo[0]) >> PAGE_SHIFT; + gfn1 = mips3_tlbpfn_to_paddr(tlb_lo[1]) >> PAGE_SHIFT; + if (gfn0 >= kvm->arch.guest_pmap_npages || + gfn1 >= kvm->arch.guest_pmap_npages) { + kvm_err("%s: Invalid gfn: [%#llx, %#llx], EHi: %#lx\n", + __func__, gfn0, gfn1, tlb->tlb_hi); + kvm_mips_dump_guest_tlbs(vcpu); return -1; + } - if (kvm_mips_map_page(kvm, mips3_tlbpfn_to_paddr(tlb_lo[1]) >> PAGE_SHIFT) < 0) + if (kvm_mips_map_page(kvm, gfn0) < 0) return -1; - pfn0 = kvm->arch.guest_pmap[mips3_tlbpfn_to_paddr(tlb_lo[0]) >> PAGE_SHIFT]; - pfn1 = kvm->arch.guest_pmap[mips3_tlbpfn_to_paddr(tlb_lo[1]) >> PAGE_SHIFT]; + if (kvm_mips_map_page(kvm, gfn1) < 0) + return -1; + + pfn0 = kvm->arch.guest_pmap[gfn0]; + pfn1 = kvm->arch.guest_pmap[gfn1]; if (hpa0) *hpa0 = pfn0 << PAGE_SHIFT; Patches currently in stable-queue which might be from james.hogan@xxxxxxxxxx are queue-3.14/mips-kvm-add-missing-gfn-range-check.patch queue-3.14/mips-kvm-propagate-kseg0-mapped-tlb-fault-errors.patch queue-3.14/mips-kvm-fix-mapped-fault-broken-commpage-handling.patch queue-3.14/mips-kvm-fix-gfn-range-check-in-kseg0-tlb-faults.patch