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| author | Ard Biesheuvel <ard.biesheuvel@linaro.org> | 2014-09-17 14:56:17 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2015-07-03 19:49:06 -0700 |
| commit | e5890a3e839ab92da899f9f6d2bfd0e9a06c55b2 (patch) | |
| tree | 77d200b0c8f497a3295f6427151566591760d93c | |
| parent | 42846f9b74fdb743c0ed4be08dc67365f98a81d4 (diff) | |
| download | lwn-e5890a3e839ab92da899f9f6d2bfd0e9a06c55b2.tar.gz lwn-e5890a3e839ab92da899f9f6d2bfd0e9a06c55b2.zip | |
arm/arm64: KVM: fix potential NULL dereference in user_mem_abort()
commit 37b544087ef3f65ca68465ba39291a07195dac26 upstream.
Handle the potential NULL return value of find_vma_intersection()
before dereferencing it.
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | arch/arm/kvm/mmu.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c index 049c56eef4de..8cd03872c83d 100644 --- a/arch/arm/kvm/mmu.c +++ b/arch/arm/kvm/mmu.c @@ -778,6 +778,12 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa, /* Let's check if we will get back a huge page backed by hugetlbfs */ down_read(¤t->mm->mmap_sem); vma = find_vma_intersection(current->mm, hva, hva + 1); + if (unlikely(!vma)) { + kvm_err("Failed to find VMA for hva 0x%lx\n", hva); + up_read(¤t->mm->mmap_sem); + return -EFAULT; + } + if (is_vm_hugetlb_page(vma)) { hugetlb = true; gfn = (fault_ipa & PMD_MASK) >> PAGE_SHIFT; |