On Fri, Sep 08, 2023 at 13:06:43 +0300, Dmitry Frolov wrote: > Reviewing the code I found that return value of function > udev_device_get_sysattr_value() is dereferenced without a check. > udev_device_get_sysattr_value() may return NULL by number of reasons. > > Signed-off-by: Dmitry Frolov <frolov@xxxxxxxxx> > --- > src/interface/interface_backend_udev.c | 11 ++++++----- > 1 file changed, 6 insertions(+), 5 deletions(-) > > diff --git a/src/interface/interface_backend_udev.c b/src/interface/interface_backend_udev.c > index a0485ddd21..c820b3ccdf 100644 > --- a/src/interface/interface_backend_udev.c > +++ b/src/interface/interface_backend_udev.c > @@ -355,10 +355,11 @@ udevConnectListAllInterfaces(virConnectPtr conn, > g_autoptr(virInterfaceDef) def = NULL; > > path = udev_list_entry_get_name(dev_entry); > - dev = udev_device_new_from_syspath(udev, path); > + if (!(dev = udev_device_new_from_syspath(udev, path))) > + continue; IMO this warants at least a VIR_DEBUG stating that the returned 'dev' struct is NULL and thus we're skipping a whole interface. > name = udev_device_get_sysname(dev); This is also documented as returning NULL on error, but virGetInterface actually checks it before use. > macaddr = udev_device_get_sysattr_value(dev, "address"); > - status = STREQ(udev_device_get_sysattr_value(dev, "operstate"), "up"); > + status = STREQ(NULLSTR(udev_device_get_sysattr_value(dev, "operstate")), "up"); For comparing strings which can be NULL we have STREQ_NULLABLE and STRNEQ_NULLABLE.
