| Message ID | ccd1fd0c5d4f4cba7fa8642ab466a82db3e9f093.1710282274.git.mst@redhat.com |
|---|---|
| State | New |
| Headers | show |
| Series | [PULL,01/68] vdpa: add back vhost_vdpa_net_first_nc_vdpa | expand |
This one is needed that it doesn't merge. Thanks! On Tue, Mar 12, 2024 at 06:27:29PM -0400, Michael S. Tsirkin wrote: > Date: Tue, 12 Mar 2024 18:27:29 -0400 > From: "Michael S. Tsirkin" <mst@redhat.com> > Subject: [PULL 38/68] hw/vfio/iommufd: Fix missing ERRP_GUARD() in > iommufd_cdev_getfd() > X-Mailer: git-send-email 2.27.0.106.g8ac3dc51b1 > > From: Zhao Liu <zhao1.liu@intel.com> > > As the comment in qapi/error, dereferencing @errp requires > ERRP_GUARD(): > > * = Why, when and how to use ERRP_GUARD() = > * > * Without ERRP_GUARD(), use of the @errp parameter is restricted: > * - It must not be dereferenced, because it may be null. > ... > * 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. > * > * Using it when it's not needed is safe, but please avoid cluttering > * the source with useless code. > > But in iommufd_cdev_getfd(), @errp is dereferenced without ERRP_GUARD(): > > if (*errp) { > error_prepend(errp, VFIO_MSG_PREFIX, path); > } > > Currently, since vfio_attach_device() - the caller of > iommufd_cdev_getfd() - is always called in DeviceClass.realize() context > and doesn't get the NULL @errp parameter, iommufd_cdev_getfd() > hasn't triggered the bug that dereferencing the NULL @errp. > > To follow the requirement of @errp, add missing ERRP_GUARD() in > iommufd_cdev_getfd(). > > Suggested-by: Markus Armbruster <armbru@redhat.com> > Signed-off-by: Zhao Liu <zhao1.liu@intel.com> > Reviewed-by: Markus Armbruster <armbru@redhat.com> > Message-Id: <20240223085653.1255438-7-zhao1.liu@linux.intel.com> > Reviewed-by: Michael S. Tsirkin <mst@redhat.com> > Signed-off-by: Michael S. Tsirkin <mst@redhat.com> > --- > hw/vfio/iommufd.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/hw/vfio/iommufd.c b/hw/vfio/iommufd.c > index 9bfddc1360..7baf49e6ee 100644 > --- a/hw/vfio/iommufd.c > +++ b/hw/vfio/iommufd.c > @@ -116,6 +116,7 @@ static void iommufd_cdev_unbind_and_disconnect(VFIODevice *vbasedev) > > static int iommufd_cdev_getfd(const char *sysfs_path, Error **errp) > { > + ERRP_GUARD(); > long int ret = -ENOTTY; > char *path, *vfio_dev_path = NULL, *vfio_path = NULL; > DIR *dir = NULL; > -- > MST >
diff --git a/hw/vfio/iommufd.c b/hw/vfio/iommufd.c index 9bfddc1360..7baf49e6ee 100644 --- a/hw/vfio/iommufd.c +++ b/hw/vfio/iommufd.c @@ -116,6 +116,7 @@ static void iommufd_cdev_unbind_and_disconnect(VFIODevice *vbasedev) static int iommufd_cdev_getfd(const char *sysfs_path, Error **errp) { + ERRP_GUARD(); long int ret = -ENOTTY; char *path, *vfio_dev_path = NULL, *vfio_path = NULL; DIR *dir = NULL;