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BUG: KMSAN: uninit-value in slab_alloc_node mm/slub.c:2704 [inline]
BUG: KMSAN: uninit-value in __kmalloc_node+0xb2d/0x11c0 mm/slub.c:3822
CPU: 1 PID: 12090 Comm: syz-executor2 Not tainted 4.19.0-rc1+ #40
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+0x14b/0x190 lib/dump_stack.c:113
 kmsan_report+0x183/0x2b0 mm/kmsan/kmsan.c:956
 __msan_warning+0x70/0xc0 mm/kmsan/kmsan_instr.c:645
 slab_alloc_node mm/slub.c:2704 [inline]
 __kmalloc_node+0xb2d/0x11c0 mm/slub.c:3822
 kmalloc_node include/linux/slab.h:555 [inline]
 kzalloc_node include/linux/slab.h:718 [inline]
 qdisc_alloc+0x148/0xd80 net/sched/sch_generic.c:820
 qdisc_create_dflt+0x127/0x3e0 net/sched/sch_generic.c:894
 mq_init+0x3f8/0x940 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:1401
 __dev_change_flags+0x3f6/0xac0 net/core/dev.c:7448
 dev_change_flags+0xca/0x230 net/core/dev.c:7517
 do_setlink+0x1718/0x6080 net/core/rtnetlink.c:2422
 rtnl_group_changelink net/core/rtnetlink.c:2883 [inline]
 rtnl_newlink+0x2257/0x39e0 net/core/rtnetlink.c:3041
 rtnetlink_rcv_msg+0xa0b/0x1530 net/core/rtnetlink.c:4711
 netlink_rcv_skb+0x36e/0x5f0 net/netlink/af_netlink.c:2454
 rtnetlink_rcv+0x50/0x60 net/core/rtnetlink.c:4729
 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline]
 netlink_unicast+0x1638/0x1720 net/netlink/af_netlink.c:1343
 netlink_sendmsg+0x1205/0x1290 net/netlink/af_netlink.c:1908
 sock_sendmsg_nosec net/socket.c:621 [inline]
 sock_sendmsg net/socket.c:631 [inline]
 ___sys_sendmsg+0xe70/0x1290 net/socket.c:2114
 __sys_sendmsg net/socket.c:2152 [inline]
 __do_sys_sendmsg net/socket.c:2161 [inline]
 __se_sys_sendmsg+0x2a3/0x3d0 net/socket.c:2159
 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2159
 do_syscall_64+0xb8/0x100 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
RIP: 0033:0x457099
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:00007efd136ebc78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007efd136ec6d4 RCX: 0000000000457099
RDX: 0000000000000000 RSI: 0000000020000140 RDI: 0000000000000005
RBP: 00000000009300a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000004d4890 R14: 00000000004c8ee5 R15: 0000000000000000

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:2719 [inline]
 __kmalloc_node_track_caller+0x9e7/0x1160 mm/slub.c:4352
 __kmalloc_reserve net/core/skbuff.c:138 [inline]
 __alloc_skb+0x2f5/0x9e0 net/core/skbuff.c:206
 alloc_skb include/linux/skbuff.h:996 [inline]
 __tcp_send_ack+0x10d/0x880 net/ipv4/tcp_output.c:3584
 tcp_send_ack+0x68/0x90 net/ipv4/tcp_output.c:3611
 tcp_delack_timer_handler+0x5b3/0xaa0 net/ipv4/tcp_timer.c:301
 tcp_delack_timer+0x1a4/0x340 net/ipv4/tcp_timer.c:328
 call_timer_fn+0x270/0x5b0 kernel/time/timer.c:1326
 expire_timers kernel/time/timer.c:1363 [inline]
 __run_timers+0xd94/0x11a0 kernel/time/timer.c:1682
 run_timer_softirq+0x2e/0x50 kernel/time/timer.c:1695
 __do_softirq+0x562/0x948 kernel/softirq.c:292
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