| Message ID | 20190212113929.31390-1-ppandit@redhat.com |
|---|---|
| State | New |
| Headers | show |
| Series | [v2] ppc: add host-serial and host-model machine attributes | expand |
On Tue, Feb 12, 2019 at 05:09:29PM +0530, P J P wrote: > From: Prasad J Pandit <pjp@fedoraproject.org> > > 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 <berrange@redhat.com> > Fix-suggested-by: Daniel P. Berrangé <berrange@redhat.com> > Signed-off-by: Prasad J Pandit <pjp@fedoraproject.org> > --- > hw/core/machine.c | 46 +++++++++++++++++++++++++++++++++++++++++++++ > hw/ppc/spapr.c | 36 +++++++++++++++++++++++++++++------ > include/hw/boards.h | 2 ++ > qemu-options.hx | 10 +++++++++- > util/qemu-config.c | 8 ++++++++ > 5 files changed, 95 insertions(+), 7 deletions(-) > > Update v2: add backward compatible properties > -> https://lists.gnu.org/archive/html/qemu-devel/2019-02/msg00593.html > > diff --git a/hw/core/machine.c b/hw/core/machine.c > index 2629515363..2d5a52476a 100644 > --- a/hw/core/machine.c > +++ b/hw/core/machine.c > @@ -476,6 +476,38 @@ static void machine_set_memory_encryption(Object *obj, const char *value, > ms->memory_encryption = g_strdup(value); > } > > +static char *machine_get_host_serial(Object *obj, Error **errp) > +{ > + MachineState *ms = MACHINE(obj); > + > + return g_strdup(ms->host_serial); > +} > + > +static void machine_set_host_serial(Object *obj, const char *value, > + Error **errp) > +{ > + MachineState *ms = MACHINE(obj); > + > + g_free(ms->host_serial); > + ms->host_serial = g_strdup(value); > +} > + > +static char *machine_get_host_model(Object *obj, Error **errp) > +{ > + MachineState *ms = MACHINE(obj); > + > + return g_strdup(ms->host_model); > +} > + > +static void machine_set_host_model(Object *obj, const char *value, > + Error **errp) > +{ > + MachineState *ms = MACHINE(obj); > + > + g_free(ms->host_model); > + ms->host_model = g_strdup(value); > +} > + > void machine_class_allow_dynamic_sysbus_dev(MachineClass *mc, const char *type) > { > strList *item = g_new0(strList, 1); > @@ -760,6 +792,18 @@ static void machine_class_init(ObjectClass *oc, void *data) > &error_abort); > object_class_property_set_description(oc, "memory-encryption", > "Set memory encryption object to use", &error_abort); > + > + object_class_property_add_str(oc, "host-serial", > + machine_get_host_serial, machine_set_host_serial, > + &error_abort); > + object_class_property_set_description(oc, "host-serial", > + "Set host's system-id to use", &error_abort); > + > + object_class_property_add_str(oc, "host-model", > + machine_get_host_model, machine_set_host_model, > + &error_abort); > + object_class_property_set_description(oc, "host-model", > + "Set host's model-id to use", &error_abort); You're adding properties to *all* machines, for something that's only used on the PAPR machine. That doesn't seem right. > } > > static void machine_class_base_init(ObjectClass *oc, void *data) > @@ -785,6 +829,8 @@ static void machine_initfn(Object *obj) > ms->dump_guest_core = true; > ms->mem_merge = true; > ms->enable_graphics = true; > + ms->host_serial = NULL; > + ms->host_model = NULL; > > /* Register notifier when init is done for sysbus sanity checks */ > ms->sysbus_notifier.notify = machine_init_notify; > diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c > index 0942f35bf8..a70667d72d 100644 > --- a/hw/ppc/spapr.c > +++ b/hw/ppc/spapr.c > @@ -1249,13 +1249,31 @@ 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 (machine->host_model && !g_str_equal(machine->host_model, "none")) { > + if (g_str_equal(machine->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=<user-string> */ > + _FDT(fdt_setprop_string(fdt, 0, "host-model", machine->host_model)); > + } > } > - if (kvmppc_get_host_serial(&buf)) { > - _FDT(fdt_setprop_string(fdt, 0, "host-serial", buf)); > - g_free(buf); > + > + if (machine->host_serial && !g_str_equal(machine->host_serial, "none")) { > + if (g_str_equal(machine->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=<user-string> */ > + _FDT(fdt_setprop_string(fdt, 0, > + "host-serial", machine->host_serial)); > + } > } > > buf = qemu_uuid_unparse_strdup(&qemu_uuid); > @@ -4080,9 +4098,15 @@ DEFINE_SPAPR_MACHINE(4_0, "4.0", true); > static void spapr_machine_3_1_class_options(MachineClass *mc) > { > 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)); I'm still not convinced maintaining super-strict backwards compat at the expense of security is a good tradeoff here, but since the code's already written, let's run with it. > + > mc->default_cpu_type = POWERPC_CPU_TYPE_NAME("power8_v2.0"); > smc->update_dt_enabled = false; > } > diff --git a/include/hw/boards.h b/include/hw/boards.h > index 02f114085f..3e63dc4501 100644 > --- a/include/hw/boards.h > +++ b/include/hw/boards.h > @@ -257,6 +257,8 @@ struct MachineState { > bool enforce_config_section; > bool enable_graphics; > char *memory_encryption; > + char *host_serial; > + char *host_model; > DeviceMemoryState *device_memory; > > ram_addr_t ram_size; > diff --git a/qemu-options.hx b/qemu-options.hx > index 521511ec13..67ac1a9959 100644 > --- a/qemu-options.hx > +++ b/qemu-options.hx > @@ -43,7 +43,9 @@ DEF("machine", HAS_ARG, QEMU_OPTION_machine, \ > " suppress-vmdesc=on|off disables self-describing migration (default=off)\n" > " nvdimm=on|off controls NVDIMM support (default=off)\n" > " enforce-config-section=on|off enforce configuration section migration (default=off)\n" > - " memory-encryption=@var{} memory encryption object to use (default=none)\n", > + " memory-encryption=@var{} memory encryption object to use (default=none)\n" > + " host-serial=none|passthrough|string controls host systemd-id (default=passthrough)\n" > + " host-model=none|passthrough|string controls host model-id (default=passthrough)\n", > QEMU_ARCH_ALL) > STEXI > @item -machine [type=]@var{name}[,prop=@var{value}[,...]] > @@ -103,6 +105,12 @@ NOTE: this parameter is deprecated. Please use @option{-global} > @option{migration.send-configuration}=@var{on|off} instead. > @item memory-encryption=@var{} > Memory encryption object to use. The default is none. > +@item host-serial=none|passthrough|string > +Pass 'system-id' parameter from host's device-tree to a guest. A user may > +disable it with 'none' or define a custom string for a guest. > +@item host-model=none|passthrough|string > +Pass 'model' paramter from host's device-tree to a guest. A user may disable > +it with 'none' or define a custom string for a guest. > @end table > ETEXI > > diff --git a/util/qemu-config.c b/util/qemu-config.c > index 9d2e278e29..86483ded34 100644 > --- a/util/qemu-config.c > +++ b/util/qemu-config.c > @@ -238,6 +238,14 @@ static QemuOptsList machine_opts = { > .help = "Up to 8 chars in set of [A-Za-z0-9. ](lower case chars" > " converted to upper case) to pass to machine" > " loader, boot manager, and guest kernel", > + },{ > + .name = "host-serial", > + .type = QEMU_OPT_STRING, > + .help = "host's system-id seen by guest", > + },{ > + .name = "host-model", > + .type = QEMU_OPT_STRING, > + .help = "host's model-id seen by guest", > }, > { /* End of list */ } > }
+-- On Wed, 13 Feb 2019, David Gibson wrote --+ | > + | > + object_class_property_add_str(oc, "host-serial", | > + machine_get_host_serial, machine_set_host_serial, | > + &error_abort); | > + object_class_property_set_description(oc, "host-serial", | > + "Set host's system-id to use", &error_abort); | > + | > + object_class_property_add_str(oc, "host-model", | > + machine_get_host_model, machine_set_host_model, | > + &error_abort); | > + object_class_property_set_description(oc, "host-model", | > + "Set host's model-id to use", &error_abort); | | You're adding properties to *all* machines, for something that's only | used on the PAPR machine. That doesn't seem right. I tried to figure out about adding these options to only spapr machine, but it does not seem straight forward as above. | > 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)); | | I'm still not convinced maintaining super-strict backwards compat at | the expense of security is a good tradeoff here, but since the code's | already written, let's run with it. I think current patch will provide a way to help fix the security issue, we can revise it further if required. Thank you. -- Prasad J Pandit / Red Hat Product Security Team 47AF CE69 3A90 54AA 9045 1053 DD13 3D32 FE5B 041F
On Fri, Feb 15, 2019 at 12:57:35AM +0530, P J P wrote: > +-- On Wed, 13 Feb 2019, David Gibson wrote --+ > | > + > | > + object_class_property_add_str(oc, "host-serial", > | > + machine_get_host_serial, machine_set_host_serial, > | > + &error_abort); > | > + object_class_property_set_description(oc, "host-serial", > | > + "Set host's system-id to use", &error_abort); > | > + > | > + object_class_property_add_str(oc, "host-model", > | > + machine_get_host_model, machine_set_host_model, > | > + &error_abort); > | > + object_class_property_set_description(oc, "host-model", > | > + "Set host's model-id to use", &error_abort); > | > | You're adding properties to *all* machines, for something that's only > | used on the PAPR machine. That doesn't seem right. > > I tried to figure out about adding these options to only spapr machine, but it > does not seem straight forward as above. It really should be. You can just put those object_class_property_add()s into spapr_machine_class_init(). > | > 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)); > | > | I'm still not convinced maintaining super-strict backwards compat at > | the expense of security is a good tradeoff here, but since the code's > | already written, let's run with it. > > I think current patch will provide a way to help fix the security issue, we > can revise it further if required. That's reasonable. > > Thank you.
diff --git a/hw/core/machine.c b/hw/core/machine.c index 2629515363..2d5a52476a 100644 --- a/hw/core/machine.c +++ b/hw/core/machine.c @@ -476,6 +476,38 @@ static void machine_set_memory_encryption(Object *obj, const char *value, ms->memory_encryption = g_strdup(value); } +static char *machine_get_host_serial(Object *obj, Error **errp) +{ + MachineState *ms = MACHINE(obj); + + return g_strdup(ms->host_serial); +} + +static void machine_set_host_serial(Object *obj, const char *value, + Error **errp) +{ + MachineState *ms = MACHINE(obj); + + g_free(ms->host_serial); + ms->host_serial = g_strdup(value); +} + +static char *machine_get_host_model(Object *obj, Error **errp) +{ + MachineState *ms = MACHINE(obj); + + return g_strdup(ms->host_model); +} + +static void machine_set_host_model(Object *obj, const char *value, + Error **errp) +{ + MachineState *ms = MACHINE(obj); + + g_free(ms->host_model); + ms->host_model = g_strdup(value); +} + void machine_class_allow_dynamic_sysbus_dev(MachineClass *mc, const char *type) { strList *item = g_new0(strList, 1); @@ -760,6 +792,18 @@ static void machine_class_init(ObjectClass *oc, void *data) &error_abort); object_class_property_set_description(oc, "memory-encryption", "Set memory encryption object to use", &error_abort); + + object_class_property_add_str(oc, "host-serial", + machine_get_host_serial, machine_set_host_serial, + &error_abort); + object_class_property_set_description(oc, "host-serial", + "Set host's system-id to use", &error_abort); + + object_class_property_add_str(oc, "host-model", + machine_get_host_model, machine_set_host_model, + &error_abort); + object_class_property_set_description(oc, "host-model", + "Set host's model-id to use", &error_abort); } static void machine_class_base_init(ObjectClass *oc, void *data) @@ -785,6 +829,8 @@ static void machine_initfn(Object *obj) ms->dump_guest_core = true; ms->mem_merge = true; ms->enable_graphics = true; + ms->host_serial = NULL; + ms->host_model = NULL; /* Register notifier when init is done for sysbus sanity checks */ ms->sysbus_notifier.notify = machine_init_notify; diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c index 0942f35bf8..a70667d72d 100644 --- a/hw/ppc/spapr.c +++ b/hw/ppc/spapr.c @@ -1249,13 +1249,31 @@ 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 (machine->host_model && !g_str_equal(machine->host_model, "none")) { + if (g_str_equal(machine->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=<user-string> */ + _FDT(fdt_setprop_string(fdt, 0, "host-model", machine->host_model)); + } } - if (kvmppc_get_host_serial(&buf)) { - _FDT(fdt_setprop_string(fdt, 0, "host-serial", buf)); - g_free(buf); + + if (machine->host_serial && !g_str_equal(machine->host_serial, "none")) { + if (g_str_equal(machine->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=<user-string> */ + _FDT(fdt_setprop_string(fdt, 0, + "host-serial", machine->host_serial)); + } } buf = qemu_uuid_unparse_strdup(&qemu_uuid); @@ -4080,9 +4098,15 @@ DEFINE_SPAPR_MACHINE(4_0, "4.0", true); static void spapr_machine_3_1_class_options(MachineClass *mc) { 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; } diff --git a/include/hw/boards.h b/include/hw/boards.h index 02f114085f..3e63dc4501 100644 --- a/include/hw/boards.h +++ b/include/hw/boards.h @@ -257,6 +257,8 @@ struct MachineState { bool enforce_config_section; bool enable_graphics; char *memory_encryption; + char *host_serial; + char *host_model; DeviceMemoryState *device_memory; ram_addr_t ram_size; diff --git a/qemu-options.hx b/qemu-options.hx index 521511ec13..67ac1a9959 100644 --- a/qemu-options.hx +++ b/qemu-options.hx @@ -43,7 +43,9 @@ DEF("machine", HAS_ARG, QEMU_OPTION_machine, \ " suppress-vmdesc=on|off disables self-describing migration (default=off)\n" " nvdimm=on|off controls NVDIMM support (default=off)\n" " enforce-config-section=on|off enforce configuration section migration (default=off)\n" - " memory-encryption=@var{} memory encryption object to use (default=none)\n", + " memory-encryption=@var{} memory encryption object to use (default=none)\n" + " host-serial=none|passthrough|string controls host systemd-id (default=passthrough)\n" + " host-model=none|passthrough|string controls host model-id (default=passthrough)\n", QEMU_ARCH_ALL) STEXI @item -machine [type=]@var{name}[,prop=@var{value}[,...]] @@ -103,6 +105,12 @@ NOTE: this parameter is deprecated. Please use @option{-global} @option{migration.send-configuration}=@var{on|off} instead. @item memory-encryption=@var{} Memory encryption object to use. The default is none. +@item host-serial=none|passthrough|string +Pass 'system-id' parameter from host's device-tree to a guest. A user may +disable it with 'none' or define a custom string for a guest. +@item host-model=none|passthrough|string +Pass 'model' paramter from host's device-tree to a guest. A user may disable +it with 'none' or define a custom string for a guest. @end table ETEXI diff --git a/util/qemu-config.c b/util/qemu-config.c index 9d2e278e29..86483ded34 100644 --- a/util/qemu-config.c +++ b/util/qemu-config.c @@ -238,6 +238,14 @@ static QemuOptsList machine_opts = { .help = "Up to 8 chars in set of [A-Za-z0-9. ](lower case chars" " converted to upper case) to pass to machine" " loader, boot manager, and guest kernel", + },{ + .name = "host-serial", + .type = QEMU_OPT_STRING, + .help = "host's system-id seen by guest", + },{ + .name = "host-model", + .type = QEMU_OPT_STRING, + .help = "host's model-id seen by guest", }, { /* End of list */ } }