Hi Vinicius, url: https://github.com/0day-ci/linux/commits/Vinicius-Costa-Gomes/ethtool-Add... base: https://git.kernel.org/pub/scm/linux/kernel/git/jkirsher/next-queue.git dev-queue If you fix the issue, kindly add following tag as appropriate Reported-by: kbuild test robot <lkp(a)intel.com&gt; Reported-by: Dan Carpenter <dan.carpenter(a)oracle.com&gt; smatch warnings: net/ethtool/preempt.c:152 ethnl_set_preempt() warn: variable dereferenced before check 'info' (see line 127) # https://github.com/0day-ci/linux/commit/5d130ebd7a21741d4fda1c8829a32353e... git remote add linux-review https://github.com/0day-ci/linux git remote update linux-review git checkout 5d130ebd7a21741d4fda1c8829a32353e10d49d5 vim +/info +152 net/ethtool/preempt.c 5d130ebd7a2174 Vinicius Costa Gomes 2020-05-15 118 int ethnl_set_preempt(struct sk_buff *skb, struct genl_info *info) 5d130ebd7a2174 Vinicius Costa Gomes 2020-05-15 119 { 5d130ebd7a2174 Vinicius Costa Gomes 2020-05-15 120 struct nlattr *tb[ETHTOOL_A_LINKINFO_MAX + 1]; 5d130ebd7a2174 Vinicius Costa Gomes 2020-05-15 121 struct ethtool_fp preempt = {}; 5d130ebd7a2174 Vinicius Costa Gomes 2020-05-15 122 struct ethnl_req_info req_info = {}; 5d130ebd7a2174 Vinicius Costa Gomes 2020-05-15 123 struct net_device *dev; 5d130ebd7a2174 Vinicius Costa Gomes 2020-05-15 124 bool mod = false; 5d130ebd7a2174 Vinicius Costa Gomes 2020-05-15 125 int ret; 5d130ebd7a2174 Vinicius Costa Gomes 2020-05-15 126 5d130ebd7a2174 Vinicius Costa Gomes 2020-05-15 @127 ret = nlmsg_parse(info->nlhdr, GENL_HDRLEN, tb, ^^^^^^^^^^^ Unchecked dereference. 5d130ebd7a2174 Vinicius Costa Gomes 2020-05-15 128 ETHTOOL_A_PREEMPT_MAX, preempt_set_policy, 5d130ebd7a2174 Vinicius Costa Gomes 2020-05-15 129 info->extack); 5d130ebd7a2174 Vinicius Costa Gomes 2020-05-15 130 if (ret < 0) 5d130ebd7a2174 Vinicius Costa Gomes 2020-05-15 131 return ret; 5d130ebd7a2174 Vinicius Costa Gomes 2020-05-15 132 5d130ebd7a2174 Vinicius Costa Gomes 2020-05-15 133 ret = ethnl_parse_header_dev_get(&req_info, 5d130ebd7a2174 Vinicius Costa Gomes 2020-05-15 134 tb[ETHTOOL_A_PREEMPT_HEADER], 5d130ebd7a2174 Vinicius Costa Gomes 2020-05-15 135 genl_info_net(info), info->extack, 5d130ebd7a2174 Vinicius Costa Gomes 2020-05-15 136 true); 5d130ebd7a2174 Vinicius Costa Gomes 2020-05-15 137 if (ret < 0) 5d130ebd7a2174 Vinicius Costa Gomes 2020-05-15 138 return ret; 5d130ebd7a2174 Vinicius Costa Gomes 2020-05-15 139 dev = req_info.dev; 5d130ebd7a2174 Vinicius Costa Gomes 2020-05-15 140 ret = -EOPNOTSUPP; 5d130ebd7a2174 Vinicius Costa Gomes 2020-05-15 141 if (!dev->ethtool_ops->get_preempt || 5d130ebd7a2174 Vinicius Costa Gomes 2020-05-15 142 !dev->ethtool_ops->set_preempt) 5d130ebd7a2174 Vinicius Costa Gomes 2020-05-15 143 goto out_dev; 5d130ebd7a2174 Vinicius Costa Gomes 2020-05-15 144 5d130ebd7a2174 Vinicius Costa Gomes 2020-05-15 145 rtnl_lock(); 5d130ebd7a2174 Vinicius Costa Gomes 2020-05-15 146 ret = ethnl_ops_begin(dev); 5d130ebd7a2174 Vinicius Costa Gomes 2020-05-15 147 if (ret < 0) 5d130ebd7a2174 Vinicius Costa Gomes 2020-05-15 148 goto out_rtnl; 5d130ebd7a2174 Vinicius Costa Gomes 2020-05-15 149 5d130ebd7a2174 Vinicius Costa Gomes 2020-05-15 150 ret = dev->ethtool_ops->get_preempt(dev, &preempt); 5d130ebd7a2174 Vinicius Costa Gomes 2020-05-15 151 if (ret < 0) { 5d130ebd7a2174 Vinicius Costa Gomes 2020-05-15 @152 if (info) ^^^^^^^^^ Check is too late to help. --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org