| Message ID | 20240229143914.1977550-5-zhao1.liu@linux.intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Cleanup up to fix missing ERRP_GUARD() for error_prepend() | expand |
On 29/02/2024 15.39, Zhao Liu wrote: > From: Zhao Liu <zhao1.liu@intel.com> > > As the comment in qapi/error, passing @errp to error_prepend() requires > ERRP_GUARD(): > > * = Why, when and how to use ERRP_GUARD() = > * > * Without ERRP_GUARD(), use of the @errp parameter is restricted: > ... > * - It should not be passed to error_prepend(), error_vprepend() or > * error_append_hint(), because that doesn't work with &error_fatal. > * ERRP_GUARD() lifts these restrictions. > * > * To use ERRP_GUARD(), add it right at the beginning of the function. > * @errp can then be used without worrying about the argument being > * NULL or &error_fatal. > > ERRP_GUARD() could avoid the case when @errp is the pointer of > error_fatal, the user can't see this additional information, because > exit() happens in error_setg earlier than information is added [1]. > > The vhost_scsi_realize() passes @errp to error_prepend(), and as a > VirtioDeviceClass.realize method, its @errp is from DeviceClass.realize > so that there is no guarantee that the @errp won't point to > @error_fatal. > > To avoid the issue like [1] said, add missing ERRP_GUARD() at the > beginning of this function. > > [1]: Issue description in the commit message of commit ae7c80a7bd73 > ("error: New macro ERRP_GUARD()"). > > Cc: "Michael S. Tsirkin" <mst@redhat.com> > Cc: Paolo Bonzini <pbonzini@redhat.com> > Cc: Fam Zheng <fam@euphon.net> > Signed-off-by: Zhao Liu <zhao1.liu@intel.com> > --- > hw/scsi/vhost-scsi.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/hw/scsi/vhost-scsi.c b/hw/scsi/vhost-scsi.c > index 58a00336c2db..ae26bc19a457 100644 > --- a/hw/scsi/vhost-scsi.c > +++ b/hw/scsi/vhost-scsi.c > @@ -220,6 +220,7 @@ static int vhost_scsi_set_workers(VHostSCSICommon *vsc, bool per_virtqueue) > > static void vhost_scsi_realize(DeviceState *dev, Error **errp) > { > + ERRP_GUARD(); > VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); > VHostSCSICommon *vsc = VHOST_SCSI_COMMON(dev); > Error *err = NULL; I think you could remove the "err" variable and the error_propagate stuff in here now. Thomas
> > @@ -220,6 +220,7 @@ static int vhost_scsi_set_workers(VHostSCSICommon *vsc, bool per_virtqueue) > > static void vhost_scsi_realize(DeviceState *dev, Error **errp) > > { > > + ERRP_GUARD(); > > VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); > > VHostSCSICommon *vsc = VHOST_SCSI_COMMON(dev); > > Error *err = NULL; > > I think you could remove the "err" variable and the error_propagate stuff in > here now. > OK, I'll. Thanks. -Zhao
diff --git a/hw/scsi/vhost-scsi.c b/hw/scsi/vhost-scsi.c index 58a00336c2db..ae26bc19a457 100644 --- a/hw/scsi/vhost-scsi.c +++ b/hw/scsi/vhost-scsi.c @@ -220,6 +220,7 @@ static int vhost_scsi_set_workers(VHostSCSICommon *vsc, bool per_virtqueue) static void vhost_scsi_realize(DeviceState *dev, Error **errp) { + ERRP_GUARD(); VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); VHostSCSICommon *vsc = VHOST_SCSI_COMMON(dev); Error *err = NULL;