From patchwork Thu Nov 22 09:29:12 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: [5/5] KVM: PPC: Book3S HV: Report correct HPT entry index when reading HPT Date: Wed, 21 Nov 2012 23:29:12 -0000 From: Paul Mackerras X-Patchwork-Id: 201206 Message-Id: <20121122092911.GF31117@bloggs.ozlabs.ibm.com> To: Alexander Graf Cc: kvm-ppc@vger.kernel.org, kvm@vger.kernel.org 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 --- arch/powerpc/kvm/book3s_64_mmu_hv.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/powerpc/kvm/book3s_64_mmu_hv.c b/arch/powerpc/kvm/book3s_64_mmu_hv.c index 2d61e01..8cc18ab 100644 --- a/arch/powerpc/kvm/book3s_64_mmu_hv.c +++ b/arch/powerpc/kvm/book3s_64_mmu_hv.c @@ -1279,7 +1279,6 @@ 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; @@ -1295,6 +1294,7 @@ 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 &&