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BUG: KMSAN: uninit-value in slab_alloc_node mm/slub.c:2705 [inline]
BUG: KMSAN: uninit-value in __kmalloc_node_track_caller+0x667/0x11d0 mm/slub.c:4353
CPU: 0 PID: 7922 Comm: syz-executor0 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_track_caller+0x667/0x11d0 mm/slub.c:4353
 __kmalloc_reserve net/core/skbuff.c:138 [inline]
 __alloc_skb+0x2ce/0x9b0 net/core/skbuff.c:206
 alloc_skb_fclone include/linux/skbuff.h:1030 [inline]
 sk_stream_alloc_skb+0x172/0xc90 net/ipv4/tcp.c:875
 tcp_sendmsg_locked+0x2a4d/0x6250 net/ipv4/tcp.c:1290
 tcp_sendmsg+0xb2/0x100 net/ipv4/tcp.c:1447
 inet_sendmsg+0x49a/0x740 net/ipv4/af_inet.c:798
 sock_sendmsg_nosec net/socket.c:642 [inline]
 sock_sendmsg net/socket.c:652 [inline]
 __sys_sendto+0x6a3/0x7c0 net/socket.c:1798
 __do_sys_sendto net/socket.c:1810 [inline]
 __se_sys_sendto net/socket.c:1806 [inline]
 __x64_sys_sendto+0x1a1/0x210 net/socket.c:1806
 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:00007f7b2b9f1c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f7b2b9f26d4 RCX: 0000000000457089
RDX: fffffffffffffedd RSI: 0000000020000280 RDI: 0000000000000005
RBP: 00000000009300a0 R08: 0000000020000080 R09: 000000000000001c
R10: 000000002000012c R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000004d4260 R14: 00000000004c8bcf 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: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_delack_timer_handler+0x5b3/0xaa0 net/ipv4/tcp_timer.c:276
 tcp_delack_timer+0x1a4/0x340 net/ipv4/tcp_timer.c:303
 call_timer_fn+0x270/0x5c0 kernel/time/timer.c:1326
 expire_timers kernel/time/timer.c:1363 [inline]
 __run_timers+0xd74/0x1170 kernel/time/timer.c:1666
 run_timer_softirq+0x43/0x70 kernel/time/timer.c:1692
 __do_softirq+0x582/0x969 kernel/softirq.c:292
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