[tnguy-net-queue:main 7/7] net/tipc/node.c:1099 tipc_node_link_down() warn: inconsistent returns '&n->lock'.

BCC: [email protected]
CC: [email protected]
CC: Intel Wired LAN <[email protected]>
TO: Jun Yang <[email protected]>
CC: Paolo Abeni <[email protected]>
CC: Tung Nguyen <[email protected]>

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/tnguy/net-queue.git main
head:   cba9ccb47e9fa4cc77692fb896cc5ab57a667882
commit: cba9ccb47e9fa4cc77692fb896cc5ab57a667882 [7/7] tipc: read le->link under the node lock in tipc_node_link_down()
:::::: branch date: 31 hours ago
:::::: commit date: 31 hours ago
config: x86_64-randconfig-161-20260812 (https://download.01.org/0day-ci/archive/20260813/[email protected]/config)
compiler: clang version 22.1.3 (https://github.com/llvm/llvm-project e9846648fd6183ee6d8cbdb4502213fcf902a211)
rustc: rustc 1.96.0 (ac68faa20 2026-05-25)
smatch: v0.5.0-9187-g5189e3fb

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <[email protected]>
| Reported-by: Dan Carpenter <[email protected]>
| Closes: https://lore.kernel.org/r/[email protected]/

smatch warnings:
net/tipc/node.c:1099 tipc_node_link_down() warn: inconsistent returns '&n->lock'.
net/tipc/node.c:1099 tipc_node_link_down() warn: inconsistent returns 'bh'.

vim +1099 net/tipc/node.c

598411d70f85dc Jon Paul Maloy 2015-07-30  1061  
598411d70f85dc Jon Paul Maloy 2015-07-30  1062  static void tipc_node_link_down(struct tipc_node *n, int bearer_id, bool delete)
598411d70f85dc Jon Paul Maloy 2015-07-30  1063  {
737889efe9713a Jon Maloy      2019-03-22  1064  	struct tipc_media_addr *maddr = NULL;
35c55c9877f8de Jon Paul Maloy 2016-06-13  1065  	int old_bearer_id = bearer_id;
cba9ccb47e9fa4 Jun Yang       2026-08-10  1066  	struct tipc_link_entry *le;
737889efe9713a Jon Maloy      2019-03-22  1067  	struct sk_buff_head xmitq;
cba9ccb47e9fa4 Jun Yang       2026-08-10  1068  	struct tipc_link *l;
73f646cec35477 Jon Paul Maloy 2015-10-15  1069  
598411d70f85dc Jon Paul Maloy 2015-07-30  1070  	__skb_queue_head_init(&xmitq);
598411d70f85dc Jon Paul Maloy 2015-07-30  1071  
cba9ccb47e9fa4 Jun Yang       2026-08-10  1072  	/* Synchronize the link lookup with bearer teardown. */
5405ff6e15f40f Jon Paul Maloy 2015-11-19  1073  	tipc_node_write_lock(n);
cba9ccb47e9fa4 Jun Yang       2026-08-10  1074  	le = &n->links[bearer_id];
cba9ccb47e9fa4 Jun Yang       2026-08-10  1075  	l = le->link;
cba9ccb47e9fa4 Jun Yang       2026-08-10  1076  	if (!l) {
cba9ccb47e9fa4 Jun Yang       2026-08-10  1077  		tipc_node_write_unlock_fast(n);
cba9ccb47e9fa4 Jun Yang       2026-08-10  1078  		return;
cba9ccb47e9fa4 Jun Yang       2026-08-10  1079  	}
cba9ccb47e9fa4 Jun Yang       2026-08-10  1080  
73f646cec35477 Jon Paul Maloy 2015-10-15  1081  	if (!tipc_link_is_establishing(l)) {
598411d70f85dc Jon Paul Maloy 2015-07-30  1082  		__tipc_node_link_down(n, &bearer_id, &xmitq, &maddr);
91986ee166cf08 Tuong Lien     2019-02-11  1083  	} else {
91986ee166cf08 Tuong Lien     2019-02-11  1084  		/* Defuse pending tipc_node_link_up() */
91986ee166cf08 Tuong Lien     2019-02-11  1085  		tipc_link_reset(l);
91986ee166cf08 Tuong Lien     2019-02-11  1086  		tipc_link_fsm_evt(l, LINK_RESET_EVT);
91986ee166cf08 Tuong Lien     2019-02-11  1087  	}
73f646cec35477 Jon Paul Maloy 2015-10-15  1088  	if (delete) {
73f646cec35477 Jon Paul Maloy 2015-10-15  1089  		kfree(l);
598411d70f85dc Jon Paul Maloy 2015-07-30  1090  		le->link = NULL;
598411d70f85dc Jon Paul Maloy 2015-07-30  1091  		n->link_cnt--;
598411d70f85dc Jon Paul Maloy 2015-07-30  1092  	}
eb18a510b5cd4d Tuong Lien     2018-12-19  1093  	trace_tipc_node_link_down(n, true, "node link down or deleted!");
5405ff6e15f40f Jon Paul Maloy 2015-11-19  1094  	tipc_node_write_unlock(n);
35c55c9877f8de Jon Paul Maloy 2016-06-13  1095  	if (delete)
35c55c9877f8de Jon Paul Maloy 2016-06-13  1096  		tipc_mon_remove_peer(n->net, n->addr, old_bearer_id);
737889efe9713a Jon Maloy      2019-03-22  1097  	if (!skb_queue_empty(&xmitq))
fc1b6d6de22087 Tuong Lien     2019-11-08  1098  		tipc_bearer_xmit(n->net, bearer_id, &xmitq, maddr, n);
598411d70f85dc Jon Paul Maloy 2015-07-30 @1099  	tipc_sk_rcv(n->net, &le->inputq);
b97bf3fd8f6a16 Per Liden      2006-01-02  1100  }
b97bf3fd8f6a16 Per Liden      2006-01-02  1101  

:::::: The code at line 1099 was first introduced by commit
:::::: 598411d70f85dcf5b5c6c2369cc48637c251b656 tipc: make resetting of links non-atomic

:::::: TO: Jon Paul Maloy <[email protected]>
:::::: CC: David S. Miller <[email protected]>

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