===================================================== BUG: KMSAN: use-after-free in l3mdev_master_ifindex_rcu+0x104/0x200 net/l3mdev/l3mdev.c:24 CPU: 0 PID: 11609 Comm: syz-executor216 Not tainted 5.6.0-rc2-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 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 l3mdev_master_ifindex_rcu+0x104/0x200 net/l3mdev/l3mdev.c:24 ipv6_dev_get_saddr+0x516/0xe10 net/ipv6/addrconf.c:1817 ip6_route_get_saddr include/net/ip6_route.h:144 [inline] ip6_dst_lookup_tail+0x1dee/0x2010 net/ipv6/ip6_output.c:1030 ip6_dst_lookup_flow+0x102/0x250 net/ipv6/ip6_output.c:1153 geneve_get_v6_dst+0x7c2/0xa00 drivers/net/geneve.c:856 geneve6_xmit_skb drivers/net/geneve.c:950 [inline] geneve_xmit+0x5d3/0x2c20 drivers/net/geneve.c:1001 __netdev_start_xmit include/linux/netdevice.h:4524 [inline] netdev_start_xmit include/linux/netdevice.h:4538 [inline] xmit_one net/core/dev.c:3470 [inline] dev_hard_start_xmit+0x531/0xab0 net/core/dev.c:3486 __dev_queue_xmit+0x37de/0x4220 net/core/dev.c:4063 dev_queue_xmit+0x4b/0x60 net/core/dev.c:4096 neigh_hh_output include/net/neighbour.h:499 [inline] neigh_output include/net/neighbour.h:508 [inline] ip6_finish_output2+0x2056/0x2640 net/ipv6/ip6_output.c:116 __ip6_finish_output+0x824/0x8e0 net/ipv6/ip6_output.c:142 ip6_finish_output+0x166/0x410 net/ipv6/ip6_output.c:152 NF_HOOK_COND include/linux/netfilter.h:296 [inline] ip6_output+0x60a/0x770 net/ipv6/ip6_output.c:175 dst_output include/net/dst.h:436 [inline] NF_HOOK include/linux/netfilter.h:307 [inline] mld_sendpack+0xeba/0x13d0 net/ipv6/mcast.c:1682 mld_send_cr net/ipv6/mcast.c:1978 [inline] mld_ifc_timer_expire+0x1158/0x1750 net/ipv6/mcast.c:2477 call_timer_fn+0x218/0x510 kernel/time/timer.c:1404 expire_timers kernel/time/timer.c:1449 [inline] __run_timers+0xcff/0x1210 kernel/time/timer.c:1773 run_timer_softirq+0x2d/0x50 kernel/time/timer.c:1786 __do_softirq+0x311/0x83d kernel/softirq.c:293 do_softirq_own_stack+0x49/0x80 arch/x86/entry/entry_64.S:1091 </IRQ> do_softirq kernel/softirq.c:338 [inline] __local_bh_enable_ip+0x184/0x1d0 kernel/softirq.c:190 __raw_spin_unlock_bh include/linux/spinlock_api_smp.h:176 [inline] _raw_spin_unlock_bh+0x4b/0x60 kernel/locking/spinlock.c:207 spin_unlock_bh include/linux/spinlock.h:383 [inline] __fib6_clean_all+0x7d0/0x940 net/ipv6/ip6_fib.c:2246 fib6_clean_all+0x97/0xb0 net/ipv6/ip6_fib.c:2255 rt6_sync_up+0x1a5/0x200 net/ipv6/route.c:4641 addrconf_notify+0x3c5e/0x5ae0 net/ipv6/addrconf.c:3567 notifier_call_chain kernel/notifier.c:83 [inline] __raw_notifier_call_chain kernel/notifier.c:361 [inline] raw_notifier_call_chain+0x12a/0x240 kernel/notifier.c:368 call_netdevice_notifiers_info net/core/dev.c:1943 [inline] netdev_state_change+0x22c/0x3a0 net/core/dev.c:1378 rtnl_linkprop+0xb15/0xc00 net/core/rtnetlink.c:3575 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 RIP: 0033:0x443e79 Code: e8 2c e8 ff ff 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 8b 09 fc ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffdbf547d08 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000443e79 RDX: 0000000000000000 RSI: 0000000020000040 RDI: 0000000000000003 RBP: 00007ffdbf547d20 R08: 0000000001bbbbbb R09: 0000000001bbbbbb R10: 0000000001bbbbbb R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000404d20 R14: 0000000000000000 R15: 0000000000000000 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 =====================================================