| Message ID | 20191130194240.10517-3-armbru@redhat.com |
|---|---|
| State | New |
| Headers | show |
| Series | Error handling fixes, may contain 4.2 material | expand |
On Sat, Nov 30, 2019 at 08:42:21PM +0100, Markus Armbruster wrote: >Functions that take an Error ** parameter to pass an error to the >caller expect the parameter to point to null. >failover_replug_primary() violates this precondition in several >places: > >* After qemu_opts_from_qdict() failed, *errp is no longer null. > Passing it to error_setg() is wrong, and will trip the assertion in > error_setv(). Messed up in commit 150ab54aa6 "net/virtio: fix > re-plugging of primary device". Simply drop the error_setg(). > >* Passing @errp to qemu_opt_set_bool(), hotplug_handler_pre_plug(), > and hotplug_handler_plug() is wrong. If one of the first two fails, > *errp is no longer null. Risks tripping the same assertion. > Moreover, continuing after such errors is unsafe. Messed up in > commit 9711cd0dfc "net/virtio: add failover support". Fix by > handling each error properly. > >failover_replug_primary() crashes when passed a null @errp. Also >messed up in commit 9711cd0dfc. This bug can't bite as no caller >actually passes null. Fix it anyway. > >Fixes: 9711cd0dfc3fa414f7f64935713c07134ae67971 >Fixes: 150ab54aa6934583180f88a2bd540bc6fc4fbff3 >Cc: Jens Freimann <jfreimann@redhat.com> >Cc: Michael S. Tsirkin <mst@redhat.com> >Signed-off-by: Markus Armbruster <armbru@redhat.com> >--- > hw/net/virtio-net.c | 19 +++++++++++++------ > 1 file changed, 13 insertions(+), 6 deletions(-) > Thanks Markus! Reviewed-by: Jens Freimann <jfreimann@redhat.com>
diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c index 87088ba374..db3d7c38e6 100644 --- a/hw/net/virtio-net.c +++ b/hw/net/virtio-net.c @@ -2795,6 +2795,7 @@ static bool failover_unplug_primary(VirtIONet *n) static bool failover_replug_primary(VirtIONet *n, Error **errp) { + Error *err = NULL; HotplugHandler *hotplug_ctrl; PCIDevice *pdev = PCI_DEVICE(n->primary_dev); @@ -2806,27 +2807,33 @@ static bool failover_replug_primary(VirtIONet *n, Error **errp) qemu_find_opts("device"), n->primary_device_dict, errp); if (!n->primary_device_opts) { - error_setg(errp, "virtio_net: couldn't find primary device opts"); - goto out; + return false; } } n->primary_bus = n->primary_dev->parent_bus; if (!n->primary_bus) { error_setg(errp, "virtio_net: couldn't find primary bus"); - goto out; + return false; } qdev_set_parent_bus(n->primary_dev, n->primary_bus); n->primary_should_be_hidden = false; qemu_opt_set_bool(n->primary_device_opts, - "partially_hotplugged", true, errp); + "partially_hotplugged", true, &err); + if (err) { + goto out; + } hotplug_ctrl = qdev_get_hotplug_handler(n->primary_dev); if (hotplug_ctrl) { - hotplug_handler_pre_plug(hotplug_ctrl, n->primary_dev, errp); + hotplug_handler_pre_plug(hotplug_ctrl, n->primary_dev, &err); + if (err) { + goto out; + } hotplug_handler_plug(hotplug_ctrl, n->primary_dev, errp); } out: - return *errp == NULL; + error_propagate(errp, err); + return !err; } static void virtio_net_handle_migration_primary(VirtIONet *n,
Functions that take an Error ** parameter to pass an error to the caller expect the parameter to point to null. failover_replug_primary() violates this precondition in several places: * After qemu_opts_from_qdict() failed, *errp is no longer null. Passing it to error_setg() is wrong, and will trip the assertion in error_setv(). Messed up in commit 150ab54aa6 "net/virtio: fix re-plugging of primary device". Simply drop the error_setg(). * Passing @errp to qemu_opt_set_bool(), hotplug_handler_pre_plug(), and hotplug_handler_plug() is wrong. If one of the first two fails, *errp is no longer null. Risks tripping the same assertion. Moreover, continuing after such errors is unsafe. Messed up in commit 9711cd0dfc "net/virtio: add failover support". Fix by handling each error properly. failover_replug_primary() crashes when passed a null @errp. Also messed up in commit 9711cd0dfc. This bug can't bite as no caller actually passes null. Fix it anyway. Fixes: 9711cd0dfc3fa414f7f64935713c07134ae67971 Fixes: 150ab54aa6934583180f88a2bd540bc6fc4fbff3 Cc: Jens Freimann <jfreimann@redhat.com> Cc: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Markus Armbruster <armbru@redhat.com> --- hw/net/virtio-net.c | 19 +++++++++++++------ 1 file changed, 13 insertions(+), 6 deletions(-)