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BUG: KMSAN: uninit-value in slab_alloc_node mm/slub.c:2705 [inline]
BUG: KMSAN: uninit-value in __kmalloc_node+0xb2d/0x1220 mm/slub.c:3823
CPU: 0 PID: 7766 Comm: syz-executor7 Not tainted 4.18.0-rc8+ #34
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+0x17c/0x1c0 lib/dump_stack.c:113
 kmsan_report+0x188/0x2a0 mm/kmsan/kmsan.c:982
 __msan_warning+0x70/0xc0 mm/kmsan/kmsan_instr.c:645
 slab_alloc_node mm/slub.c:2705 [inline]
 __kmalloc_node+0xb2d/0x1220 mm/slub.c:3823
 kmalloc_node include/linux/slab.h:555 [inline]
 kzalloc_node include/linux/slab.h:718 [inline]
 qdisc_alloc+0x14b/0xd30 net/sched/sch_generic.c:820
 qdisc_create_dflt+0x127/0x3e0 net/sched/sch_generic.c:894
 mq_init+0x3d8/0x910 net/sched/sch_mq.c:95
 qdisc_create_dflt net/sched/sch_generic.c:901 [inline]
 attach_default_qdiscs net/sched/sch_generic.c:1036 [inline]
 dev_activate+0xb2e/0x1500 net/sched/sch_generic.c:1075
 __dev_open+0x77c/0x870 net/core/dev.c:1402
 __dev_change_flags+0x3f6/0xac0 net/core/dev.c:6991
 dev_change_flags+0xca/0x230 net/core/dev.c:7060
 do_setlink+0x16c9/0x6080 net/core/rtnetlink.c:2376
 rtnl_group_changelink net/core/rtnetlink.c:2837 [inline]
 rtnl_newlink+0x2257/0x39e0 net/core/rtnetlink.c:2995
 rtnetlink_rcv_msg+0xa0b/0x1530 net/core/rtnetlink.c:4665
 netlink_rcv_skb+0x36e/0x5f0 net/netlink/af_netlink.c:2455
 rtnetlink_rcv+0x50/0x60 net/core/rtnetlink.c:4683
 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline]
 netlink_unicast+0x1492/0x1740 net/netlink/af_netlink.c:1343
 netlink_sendmsg+0x114c/0x1350 net/netlink/af_netlink.c:1908
 sock_sendmsg_nosec net/socket.c:642 [inline]
 sock_sendmsg net/socket.c:652 [inline]
 ___sys_sendmsg+0xe32/0x1250 net/socket.c:2126
 __sys_sendmsg net/socket.c:2164 [inline]
 __do_sys_sendmsg net/socket.c:2173 [inline]
 __se_sys_sendmsg net/socket.c:2171 [inline]
 __x64_sys_sendmsg+0x32d/0x460 net/socket.c:2171
 do_syscall_64+0x15b/0x220 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
RIP: 0033:0x457089
Code: fd b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 cb b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 
RSP: 002b:00007f502027dc78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f502027e6d4 RCX: 0000000000457089
RDX: 0000000000000000 RSI: 0000000020000100 RDI: 0000000000000006
RBP: 0000000000930320 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000004d3ce0 R14: 00000000004c8929 R15: 0000000000000004

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:256 [inline]
 kmsan_internal_poison_shadow+0xb8/0x1b0 mm/kmsan/kmsan.c:181
 kmsan_kmalloc+0x98/0x100 mm/kmsan/kmsan_hooks.c:91
 kmsan_slab_alloc+0x10/0x20 mm/kmsan/kmsan_hooks.c:100
 slab_post_alloc_hook mm/slab.h:446 [inline]
 slab_alloc_node mm/slub.c:2720 [inline]
 __kmalloc_node_track_caller+0xb4c/0x11d0 mm/slub.c:4353
 __kmalloc_reserve net/core/skbuff.c:138 [inline]
 __alloc_skb+0x2ce/0x9b0 net/core/skbuff.c:206
 alloc_skb include/linux/skbuff.h:988 [inline]
 __tcp_send_ack+0x10a/0x830 net/ipv4/tcp_output.c:3597
 tcp_send_ack+0x68/0x90 net/ipv4/tcp_output.c:3624
 tcp_compressed_ack_kick+0x15a/0x2e0 net/ipv4/tcp_timer.c:719
 __run_hrtimer kernel/time/hrtimer.c:1398 [inline]
 __hrtimer_run_queues+0xbfc/0x15b0 kernel/time/hrtimer.c:1460
 hrtimer_run_softirq+0x1b3/0x2b0 kernel/time/hrtimer.c:1474
 __do_softirq+0x582/0x969 kernel/softirq.c:292
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