From 13e153f01b4f2a3e199202b34a247d83c176f21a Mon Sep 17 00:00:00 2001 From: Prasad J Pandit Date: Mon, 18 Feb 2019 23:43:49 +0530 Subject: [PATCH] ppc: add host-serial and host-model machine attributes (CVE-2019-8934) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit On ppc hosts, hypervisor shares following system attributes - /proc/device-tree/system-id - /proc/device-tree/model with a guest. This could lead to information leakage and misuse.[*] Add machine attributes to control such system information exposure to a guest. [*] https://wiki.openstack.org/wiki/OSSN/OSSN-0028 Reported-by: Daniel P. Berrangé Fix-suggested-by: Daniel P. Berrangé Signed-off-by: Prasad J Pandit Message-Id: <20190218181349.23885-1-ppandit@redhat.com> Reviewed-by: Daniel P. Berrangé Reviewed-by: Greg Kurz Signed-off-by: David Gibson CVE: CVE-2019-8934 Upstream-Status: Backport [https://github.com/qemu/qemu/commit/27461d69a0f108dea756419251acc3ea65198f1b] Signed-off-by: Dan Tran --- hw/ppc/spapr.c | 128 ++++++++++++++++++++++++++++++++++++++--- include/hw/ppc/spapr.h | 2 + 2 files changed, 123 insertions(+), 7 deletions(-) diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c index 421b2dd09b..069d678ee0 100644 --- a/hw/ppc/spapr.c +++ b/hw/ppc/spapr.c @@ -1266,13 +1266,30 @@ static void *spapr_build_fdt(sPAPRMachineState *spapr, * Add info to guest to indentify which host is it being run on * and what is the uuid of the guest */ - if (kvmppc_get_host_model(&buf)) { - _FDT(fdt_setprop_string(fdt, 0, "host-model", buf)); - g_free(buf); + if (spapr->host_model && !g_str_equal(spapr->host_model, "none")) { + if (g_str_equal(spapr->host_model, "passthrough")) { + /* -M host-model=passthrough */ + if (kvmppc_get_host_model(&buf)) { + _FDT(fdt_setprop_string(fdt, 0, "host-model", buf)); + g_free(buf); + } + } else { + /* -M host-model= */ + _FDT(fdt_setprop_string(fdt, 0, "host-model", spapr->host_model)); + } } - if (kvmppc_get_host_serial(&buf)) { - _FDT(fdt_setprop_string(fdt, 0, "host-serial", buf)); - g_free(buf); + + if (spapr->host_serial && !g_str_equal(spapr->host_serial, "none")) { + if (g_str_equal(spapr->host_serial, "passthrough")) { + /* -M host-serial=passthrough */ + if (kvmppc_get_host_serial(&buf)) { + _FDT(fdt_setprop_string(fdt, 0, "host-serial", buf)); + g_free(buf); + } + } else { + /* -M host-serial= */ + _FDT(fdt_setprop_string(fdt, 0, "host-serial", spapr->host_serial)); + } } buf = qemu_uuid_unparse_strdup(&qemu_uuid); @@ -3027,6 +3044,73 @@ static void spapr_set_vsmt(Object *obj, Visitor *v, const char *name, visit_type_uint32(v, name, (uint32_t *)opaque, errp); } +static char *spapr_get_ic_mode(Object *obj, Error **errp) +{ + sPAPRMachineState *spapr = SPAPR_MACHINE(obj); + + if (spapr->irq == &spapr_irq_xics_legacy) { + return g_strdup("legacy"); + } else if (spapr->irq == &spapr_irq_xics) { + return g_strdup("xics"); + } else if (spapr->irq == &spapr_irq_xive) { + return g_strdup("xive"); + } else if (spapr->irq == &spapr_irq_dual) { + return g_strdup("dual"); + } + g_assert_not_reached(); +} + +static void spapr_set_ic_mode(Object *obj, const char *value, Error **errp) +{ + sPAPRMachineState *spapr = SPAPR_MACHINE(obj); + + if (SPAPR_MACHINE_GET_CLASS(spapr)->legacy_irq_allocation) { + error_setg(errp, "This machine only uses the legacy XICS backend, don't pass ic-mode"); + return; + } + + /* The legacy IRQ backend can not be set */ + if (strcmp(value, "xics") == 0) { + spapr->irq = &spapr_irq_xics; + } else if (strcmp(value, "xive") == 0) { + spapr->irq = &spapr_irq_xive; + } else if (strcmp(value, "dual") == 0) { + spapr->irq = &spapr_irq_dual; + } else { + error_setg(errp, "Bad value for \"ic-mode\" property"); + } +} + +static char *spapr_get_host_model(Object *obj, Error **errp) +{ + sPAPRMachineState *spapr = SPAPR_MACHINE(obj); + + return g_strdup(spapr->host_model); +} + +static void spapr_set_host_model(Object *obj, const char *value, Error **errp) +{ + sPAPRMachineState *spapr = SPAPR_MACHINE(obj); + + g_free(spapr->host_model); + spapr->host_model = g_strdup(value); +} + +static char *spapr_get_host_serial(Object *obj, Error **errp) +{ + sPAPRMachineState *spapr = SPAPR_MACHINE(obj); + + return g_strdup(spapr->host_serial); +} + +static void spapr_set_host_serial(Object *obj, const char *value, Error **errp) +{ + sPAPRMachineState *spapr = SPAPR_MACHINE(obj); + + g_free(spapr->host_serial); + spapr->host_serial = g_strdup(value); +} + static void spapr_instance_init(Object *obj) { sPAPRMachineState *spapr = SPAPR_MACHINE(obj); @@ -3063,6 +3147,25 @@ static void spapr_instance_init(Object *obj) " the host's SMT mode", &error_abort); object_property_add_bool(obj, "vfio-no-msix-emulation", spapr_get_msix_emulation, NULL, NULL); + + /* The machine class defines the default interrupt controller mode */ + spapr->irq = smc->irq; + object_property_add_str(obj, "ic-mode", spapr_get_ic_mode, + spapr_set_ic_mode, NULL); + object_property_set_description(obj, "ic-mode", + "Specifies the interrupt controller mode (xics, xive, dual)", + NULL); + + object_property_add_str(obj, "host-model", + spapr_get_host_model, spapr_set_host_model, + &error_abort); + object_property_set_description(obj, "host-model", + "Set host's model-id to use - none|passthrough|string", &error_abort); + object_property_add_str(obj, "host-serial", + spapr_get_host_serial, spapr_set_host_serial, + &error_abort); + object_property_set_description(obj, "host-serial", + "Set host's system-id to use - none|passthrough|string", &error_abort); } static void spapr_machine_finalizefn(Object *obj) @@ -4067,7 +4170,18 @@ static void spapr_machine_3_0_instance_options(MachineState *machine) static void spapr_machine_3_0_class_options(MachineClass *mc) { - /* Defaults for the latest behaviour inherited from the base class */ + sPAPRMachineClass *smc = SPAPR_MACHINE_CLASS(mc); + static GlobalProperty compat[] = { + { TYPE_SPAPR_MACHINE, "host-model", "passthrough" }, + { TYPE_SPAPR_MACHINE, "host-serial", "passthrough" }, + }; + + spapr_machine_4_0_class_options(mc); + compat_props_add(mc->compat_props, hw_compat_3_1, hw_compat_3_1_len); + compat_props_add(mc->compat_props, compat, G_N_ELEMENTS(compat)); + + mc->default_cpu_type = POWERPC_CPU_TYPE_NAME("power8_v2.0"); + smc->update_dt_enabled = false; } DEFINE_SPAPR_MACHINE(3_0, "3.0", true); diff --git a/include/hw/ppc/spapr.h b/include/hw/ppc/spapr.h index 7e5de1a6fd..4c69a55374 100644 --- a/include/hw/ppc/spapr.h +++ b/include/hw/ppc/spapr.h @@ -165,6 +165,8 @@ struct sPAPRMachineState { /*< public >*/ char *kvm_type; + char *host_model; + char *host_serial; const char *icp_type; -- 2.22.0.vfs.1.1.57.gbaf16c8