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BUG: KMSAN: use-after-free in ip6_ignore_linkdown include/net/addrconf.h:402 [inline]
BUG: KMSAN: use-after-free in find_match+0x317/0x1480 net/ipv6/route.c:749
CPU: 1 PID: 12116 Comm: kworker/u4:0 Not tainted 5.6.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: krdsd rds_connect_worker
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1c9/0x220 lib/dump_stack.c:118
 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:118
 __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:215
 ip6_ignore_linkdown include/net/addrconf.h:402 [inline]
 find_match+0x317/0x1480 net/ipv6/route.c:749
 __find_rr_leaf+0x3f9/0x1160 net/ipv6/route.c:837
 find_rr_leaf net/ipv6/route.c:858 [inline]
 rt6_select net/ipv6/route.c:902 [inline]
 fib6_table_lookup+0x586/0x1420 net/ipv6/route.c:2170
 ip6_pol_route+0x203/0x2960 net/ipv6/route.c:2206
 ip6_pol_route_input+0x123/0x140 net/ipv6/route.c:2264
 fib6_rule_lookup+0x38f/0xa10 net/ipv6/fib6_rules.c:114
 ip6_route_input_lookup net/ipv6/route.c:2276 [inline]
 ip6_route_input+0xb9d/0xcf0 net/ipv6/route.c:2445
 ip6_rcv_finish_core+0x1f9/0x470 net/ipv6/ip6_input.c:63
 ip6_rcv_finish net/ipv6/ip6_input.c:74 [inline]
 NF_HOOK include/linux/netfilter.h:307 [inline]
 ipv6_rcv+0x628/0x710 net/ipv6/ip6_input.c:306
 __netif_receive_skb_one_core net/core/dev.c:5198 [inline]
 __netif_receive_skb net/core/dev.c:5312 [inline]
 process_backlog+0xa41/0x1410 net/core/dev.c:6144
 napi_poll net/core/dev.c:6582 [inline]
 net_rx_action+0x786/0x1aa0 net/core/dev.c:6650
 __do_softirq+0x311/0x83d kernel/softirq.c:293
 invoke_softirq kernel/softirq.c:375 [inline]
 irq_exit+0x230/0x280 kernel/softirq.c:416
 exiting_irq+0xe/0x10 arch/x86/include/asm/apic.h:546
 smp_apic_timer_interrupt+0x48/0x70 arch/x86/kernel/apic/apic.c:1149
 apic_timer_interrupt+0x2e/0x40 arch/x86/entry/entry_64.S:834
 </IRQ>
RIP: 0010:__msan_instrument_asm_store+0x101/0x120 mm/kmsan/kmsan_instr.c:78
Code: f6 31 d2 e8 91 f3 ff ff be ff ff ff ff 65 0f c1 35 24 64 34 6b ff ce 75 1a e8 cb f5 30 ff 4c 89 7d e0 ff 75 e0 9d 48 83 c4 10 <5b> 41 5e 41 5f 5d c3 0f 0b 48 c7 c7 06 4c 08 a2 31 c0 e8 5a 6e 48
RSP: 0018:ffffb8bb012779c8 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13
RAX: ffff9971049d4ff8 RBX: ffff99710867cff8 RCX: 0000000000000003
RDX: 0000000000000002 RSI: 0000000000000000 RDI: ffff99710867cff8
RBP: ffffb8bb012779e0 R08: fffff5858000000f R09: ffff99712fffb000
R10: 000000000000000d R11: ffffffffa160083d R12: ffff99710867cff8
R13: ffff99710867cec0 R14: 0000000000000008 R15: 0000000000000282
 sk_dst_set include/net/sock.h:1910 [inline]
 sk_dst_reset include/net/sock.h:1923 [inline]
 __inet_bind+0xd8f/0xfe0 net/ipv4/af_inet.c:543
 inet_bind+0x21d/0x300 net/ipv4/af_inet.c:453
 rds_tcp_conn_path_connect+0x5cf/0xb80 net/rds/tcp_connect.c:144
 rds_connect_worker+0x2a6/0x470 net/rds/threads.c:176
 process_one_work+0x1555/0x1f40 kernel/workqueue.c:2264
 worker_thread+0xef6/0x2450 kernel/workqueue.c:2410
 kthread+0x4b5/0x4f0 kernel/kthread.c:256
 ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:353

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:144 [inline]
 kmsan_internal_poison_shadow+0x66/0xd0 mm/kmsan/kmsan.c:127
 kmsan_slab_free+0x6e/0xb0 mm/kmsan/kmsan_hooks.c:107
 slab_free_freelist_hook mm/slub.c:1477 [inline]
 slab_free mm/slub.c:3040 [inline]
 kfree+0x565/0x30a0 mm/slub.c:3993
 __netdev_name_node_alt_destroy net/core/dev.c:322 [inline]
 netdev_name_node_alt_destroy+0x587/0x690 net/core/dev.c:334
 rtnl_alt_ifname net/core/rtnetlink.c:3518 [inline]
 rtnl_linkprop+0x939/0xc00 net/core/rtnetlink.c:3567
 rtnl_dellinkprop+0x9d/0xb0 net/core/rtnetlink.c:3588
 rtnetlink_rcv_msg+0x1153/0x1570 net/core/rtnetlink.c:5438
 netlink_rcv_skb+0x451/0x650 net/netlink/af_netlink.c:2477
 rtnetlink_rcv+0x50/0x60 net/core/rtnetlink.c:5456
 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline]
 netlink_unicast+0xf9e/0x1100 net/netlink/af_netlink.c:1328
 netlink_sendmsg+0x1246/0x14d0 net/netlink/af_netlink.c:1917
 sock_sendmsg_nosec net/socket.c:652 [inline]
 sock_sendmsg net/socket.c:672 [inline]
 ____sys_sendmsg+0x12b6/0x1350 net/socket.c:2343
 ___sys_sendmsg net/socket.c:2397 [inline]
 __sys_sendmsg+0x451/0x5f0 net/socket.c:2430
 __do_sys_sendmsg net/socket.c:2439 [inline]
 __se_sys_sendmsg+0x97/0xb0 net/socket.c:2437
 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2437
 do_syscall_64+0xb8/0x160 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
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