Hello Jiri Pirko,
The patch 7960d1daf278: "net: sched: use block index as a handle
instead of qdisc when block is shared" from Jan 17, 2018, leads to
the following static checker warning:
net/sched/cls_api.c:1362 tc_dump_tfilter()
error: uninitialized symbol 'parent'.
net/sched/cls_api.c
1296 static int tc_dump_tfilter(struct sk_buff *skb, struct netlink_callback *cb)
1297 {
1298 struct net *net = sock_net(skb->sk);
1299 struct nlattr *tca[TCA_MAX + 1];
1300 struct Qdisc *q = NULL;
1301 struct tcf_block *block;
1302 struct tcf_chain *chain;
1303 struct tcmsg *tcm = nlmsg_data(cb->nlh);
1304 long index_start;
1305 long index;
1306 u32 parent;
^^^^^^^^^^
1307 int err;
1308
1309 if (nlmsg_len(cb->nlh) < sizeof(*tcm))
1310 return skb->len;
1311
1312 err = nlmsg_parse(cb->nlh, sizeof(*tcm), tca, TCA_MAX, NULL, NULL);
1313 if (err)
1314 return err;
1315
1316 if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK) {
1317 block = tcf_block_lookup(net, tcm->tcm_block_index);
1318 if (!block)
1319 goto out;
Assume tcf_block_lookup() succeeds.
1320 } else {
1321 const struct Qdisc_class_ops *cops;
1322 struct net_device *dev;
1323 unsigned long cl = 0;
1324
1325 dev = __dev_get_by_index(net, tcm->tcm_ifindex);
1326 if (!dev)
1327 return skb->len;
1328
1329 parent = tcm->tcm_parent;
1330 if (!parent) {
1331 q = dev->qdisc;
1332 parent = q->handle;
1333 } else {
1334 q = qdisc_lookup(dev, TC_H_MAJ(tcm->tcm_parent));
1335 }
1336 if (!q)
1337 goto out;
1338 cops = q->ops->cl_ops;
1339 if (!cops)
1340 goto out;
1341 if (!cops->tcf_block)
1342 goto out;
1343 if (TC_H_MIN(tcm->tcm_parent)) {
1344 cl = cops->find(q, tcm->tcm_parent);
1345 if (cl == 0)
1346 goto out;
1347 }
1348 block = cops->tcf_block(q, cl, NULL);
1349 if (!block)
1350 goto out;
1351 if (tcf_block_shared(block))
1352 q = NULL;
1353 }
1354
1355 index_start = cb->args[0];
1356 index = 0;
1357
1358 list_for_each_entry(chain, &block->chain_list, list) {
1359 if (tca[TCA_CHAIN] &&
1360 nla_get_u32(tca[TCA_CHAIN]) != chain->index)
1361 continue;
1362 if (!tcf_chain_dump(chain, q, parent, skb, cb,
^^^^^^
Smatch thinks "parent" is uninitialized here.
1363 index_start, &index))
1364 break;
1365 }
1366
1367 cb->args[0] = index;
1368
1369 out:
1370 return skb->len;
1371 }
regards,
dan carpenter
--
To unsubscribe from this list: send the line "unsubscribe kernel-janitors" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
