From patchwork Thu Dec 6 00:40:58 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: [09/28] KVM: PPC: Book3S HV: Report correct HPT entry index when reading HPT From: Alexander Graf X-Patchwork-Id: 204065 Message-Id: <1354754477-15472-10-git-send-email-agraf@suse.de> To: Marcelo Tosatti Cc: Gleb Natapov , kvm-ppc , KVM list , Paul Mackerras Date: Thu, 6 Dec 2012 01:40:58 +0100 From: Paul Mackerras This fixes a bug in the code which allows userspace to read out the contents of the guest's hashed page table (HPT). On the second and subsequent passes through the HPT, when we are reporting only those entries that have changed, we were incorrectly initializing the index field of the header with the index of the first entry we skipped rather than the first changed entry. This fixes it. Signed-off-by: Paul Mackerras Signed-off-by: Alexander Graf --- arch/powerpc/kvm/book3s_64_mmu_hv.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/arch/powerpc/kvm/book3s_64_mmu_hv.c b/arch/powerpc/kvm/book3s_64_mmu_hv.c index 1029e22..ac6b5ac 100644 --- a/arch/powerpc/kvm/book3s_64_mmu_hv.c +++ b/arch/powerpc/kvm/book3s_64_mmu_hv.c @@ -1282,7 +1282,6 @@ static ssize_t kvm_htab_read(struct file *file, char __user *buf, while (nb + sizeof(hdr) + HPTE_SIZE < count) { /* Initialize header */ hptr = (struct kvm_get_htab_header __user *)buf; - hdr.index = i; hdr.n_valid = 0; hdr.n_invalid = 0; nw = nb; @@ -1298,6 +1297,7 @@ static ssize_t kvm_htab_read(struct file *file, char __user *buf, ++revp; } } + hdr.index = i; /* Grab a series of valid entries */ while (i < kvm->arch.hpt_npte &&