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@swemel.ru> --- 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.