KVM: PPC: Book3S HV: XIVE: Fix potential page leak on error path

We need to check the host page size is big enough to accomodate the
EQ. Let's do this before taking a reference on the EQ page to avoid
a potential leak if the check fails.

Cc: stable@vger.kernel.org # v5.2
Fixes: 13ce3297c5 ("KVM: PPC: Book3S HV: XIVE: Add controls for the EQ configuration")
Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
This commit is contained in:
Greg Kurz 2019-11-13 17:46:19 +01:00 committed by Paul Mackerras
parent 31a88c82b4
commit 30486e7209

View File

@ -630,12 +630,6 @@ static int kvmppc_xive_native_set_queue_config(struct kvmppc_xive *xive,
srcu_idx = srcu_read_lock(&kvm->srcu);
gfn = gpa_to_gfn(kvm_eq.qaddr);
page = gfn_to_page(kvm, gfn);
if (is_error_page(page)) {
srcu_read_unlock(&kvm->srcu, srcu_idx);
pr_err("Couldn't get queue page %llx!\n", kvm_eq.qaddr);
return -EINVAL;
}
page_size = kvm_host_page_size(kvm, gfn);
if (1ull << kvm_eq.qshift > page_size) {
@ -644,6 +638,13 @@ static int kvmppc_xive_native_set_queue_config(struct kvmppc_xive *xive,
return -EINVAL;
}
page = gfn_to_page(kvm, gfn);
if (is_error_page(page)) {
srcu_read_unlock(&kvm->srcu, srcu_idx);
pr_err("Couldn't get queue page %llx!\n", kvm_eq.qaddr);
return -EINVAL;
}
qaddr = page_to_virt(page) + (kvm_eq.qaddr & ~PAGE_MASK);
srcu_read_unlock(&kvm->srcu, srcu_idx);