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BUG: KMSAN: uninit-value in __list_add_valid+0x2a4/0x450 lib/list_debug.c:26
CPU: 0 PID: 17425 Comm: syz-executor4 Not tainted 4.17.0+ #17
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x185/0x1d0 lib/dump_stack.c:113
 kmsan_report+0x188/0x2a0 mm/kmsan/kmsan.c:1368
 __msan_warning_32+0x70/0xc0 mm/kmsan/kmsan_instr.c:634
 __list_add_valid+0x2a4/0x450 lib/list_debug.c:26
 __list_add include/linux/list.h:60 [inline]
 list_add_tail include/linux/list.h:93 [inline]
 cma_listen_on_all drivers/infiniband/core/cma.c:2301 [inline]
 rdma_listen+0x65f/0x10f0 drivers/infiniband/core/cma.c:3327
 ucma_listen+0x4e9/0x630 drivers/infiniband/core/ucma.c:1096
 ucma_write+0x57e/0x5f0 drivers/infiniband/core/ucma.c:1676
 __vfs_write+0x1aa/0x9f0 fs/read_write.c:485
 vfs_write+0x467/0x8c0 fs/read_write.c:549
 ksys_write fs/read_write.c:598 [inline]
 __do_sys_write fs/read_write.c:610 [inline]
 __se_sys_write fs/read_write.c:607 [inline]
 __x64_sys_write+0x1bf/0x3e0 fs/read_write.c:607
 do_syscall_64+0x15b/0x230 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
RIP: 0033:0x455ab9
RSP: 002b:00007f5161420c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f51614216d4 RCX: 0000000000455ab9
RDX: 0000000000000010 RSI: 0000000020000000 RDI: 0000000000000014
RBP: 000000000072c098 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000004c2714 R14: 00000000004d3f98 R15: 0000000000000003

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:287 [inline]
 kmsan_internal_poison_shadow+0xb8/0x1b0 mm/kmsan/kmsan.c:197
 kmsan_kmalloc+0x94/0x100 mm/kmsan/kmsan.c:323
 kmsan_slab_alloc+0x10/0x20 mm/kmsan/kmsan.c:330
 slab_post_alloc_hook mm/slab.h:446 [inline]
 slab_alloc_node mm/slub.c:2753 [inline]
 __kmalloc_node_track_caller+0xb35/0x11b0 mm/slub.c:4395
 __kmalloc_reserve net/core/skbuff.c:138 [inline]
 __alloc_skb+0x2cb/0x9e0 net/core/skbuff.c:206
 alloc_skb include/linux/skbuff.h:988 [inline]
 nlmsg_new include/net/netlink.h:511 [inline]
 inet6_rt_notify+0x291/0x630 net/ipv6/route.c:4807
 fib6_del_route net/ipv6/ip6_fib.c:1732 [inline]
 fib6_del+0x1c7d/0x2210 net/ipv6/ip6_fib.c:1769
 fib6_clean_node+0x39e/0x6b0 net/ipv6/ip6_fib.c:1930
 fib6_walk_continue+0xc99/0xe20 net/ipv6/ip6_fib.c:1853
 fib6_walk net/ipv6/ip6_fib.c:1901 [inline]
 fib6_clean_tree net/ipv6/ip6_fib.c:1978 [inline]
 __fib6_clean_all+0x53d/0x840 net/ipv6/ip6_fib.c:1994
 fib6_clean_all+0x90/0xa0 net/ipv6/ip6_fib.c:2005
 rt6_sync_down_dev net/ipv6/route.c:3924 [inline]
 rt6_disable_ip+0x104/0x9b0 net/ipv6/route.c:3929
 addrconf_ifdown+0x237/0x2890 net/ipv6/addrconf.c:3621
 addrconf_notify+0x1dae/0x5930 net/ipv6/addrconf.c:3415
 notifier_call_chain kernel/notifier.c:93 [inline]
 __raw_notifier_call_chain kernel/notifier.c:394 [inline]
 raw_notifier_call_chain+0x13e/0x240 kernel/notifier.c:401
 call_netdevice_notifiers_info net/core/dev.c:1734 [inline]
 call_netdevice_notifiers net/core/dev.c:1752 [inline]
 dev_close_many+0x62a/0xa00 net/core/dev.c:1504
 rollback_registered_many+0x9ee/0x1d70 net/core/dev.c:7413
 rollback_registered net/core/dev.c:7478 [inline]
 unregister_netdevice_queue+0x579/0xab0 net/core/dev.c:8520
 unregister_netdevice include/linux/netdevice.h:2494 [inline]
 __tun_detach+0x25aa/0x3310 drivers/net/tun.c:728
 tun_detach drivers/net/tun.c:745 [inline]
 tun_chr_close+0xda/0x1c0 drivers/net/tun.c:3262
 __fput+0x458/0xa30 fs/file_table.c:209
 ____fput+0x37/0x40 fs/file_table.c:243
 task_work_run+0x22e/0x2b0 kernel/task_work.c:113
 exit_task_work include/linux/task_work.h:22 [inline]
 do_exit+0x110e/0x3930 kernel/exit.c:867
 do_group_exit+0x1a0/0x360 kernel/exit.c:970
 __do_sys_exit_group+0x21/0x30 kernel/exit.c:981
 __se_sys_exit_group+0x14/0x20 kernel/exit.c:979
 __x64_sys_exit_group+0x4c/0x50 kernel/exit.c:979
 do_syscall_64+0x15b/0x230 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
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