syzbot

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BUG: KMSAN: uninit-value in neigh_invalidate+0x359/0x8e0 net/core/neighbour.c:996
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.3.0-rc7+ #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+0x191/0x1f0 lib/dump_stack.c:113
 kmsan_report+0x13a/0x2b0 mm/kmsan/kmsan_report.c:108
 __msan_warning+0x73/0xe0 mm/kmsan/kmsan_instr.c:250
 dst_link_failure include/net/dst.h:418 [inline]
 arp_error_report+0x124/0x1a0 net/ipv4/arp.c:293
 neigh_invalidate+0x359/0x8e0 net/core/neighbour.c:996
 neigh_timer_handler+0xda4/0x1450 net/core/neighbour.c:1082
 call_timer_fn+0x232/0x530 kernel/time/timer.c:1322
 expire_timers kernel/time/timer.c:1366 [inline]
 __run_timers+0xcdc/0x11a0 kernel/time/timer.c:1685
 run_timer_softirq+0x2d/0x50 kernel/time/timer.c:1698
 __do_softirq+0x4a1/0x83a kernel/softirq.c:293
 invoke_softirq kernel/softirq.c:375 [inline]
 irq_exit+0x230/0x280 kernel/softirq.c:416
 exiting_irq+0xe/0x10 arch/x86/include/asm/apic.h:537
 smp_apic_timer_interrupt+0x48/0x70 arch/x86/kernel/apic/apic.c:1135
 apic_timer_interrupt+0x2e/0x40 arch/x86/entry/entry_64.S:837
 </IRQ>
RIP: 0010:default_idle+0x53/0x90 arch/x86/kernel/process.c:581
Code: 13 ee eb f2 44 8b 35 94 79 d2 01 48 c7 c7 78 d5 25 90 e8 c0 9b b1 f3 83 38 00 75 31 45 85 f6 7e 07 0f 00 2d 8f f3 4d 00 fb f4 <65> 8b 35 2e 57 af 71 c7 03 00 00 00 00 c7 43 08 00 00 00 00 bf ff
RSP: 0018:ffff8881280dfe10 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: ffff888217c47578 RBX: ffff8881280b09a0 RCX: ccccccccccccd000
RDX: ffff888207e40578 RSI: ffffea000a76d630 RDI: 000000001025d578
RBP: ffff8881280dfe20 R08: 0000000000000000 R09: ffff8881280b8002
R10: 0000000000000004 R11: ffffffff8e535bb0 R12: 0000000000000001
R13: 0000000000000000 R14: 0000000000000000 R15: ffff8881280b09a0
 arch_cpu_idle+0x25/0x30 arch/x86/kernel/process.c:571
 default_idle_call kernel/sched/idle.c:94 [inline]
 cpuidle_idle_call kernel/sched/idle.c:154 [inline]
 do_idle+0x1d7/0x790 kernel/sched/idle.c:263
 cpu_startup_entry+0x45/0x50 kernel/sched/idle.c:354
 start_secondary+0x370/0x470 arch/x86/kernel/smpboot.c:264
 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:241

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:150 [inline]
 kmsan_internal_poison_shadow+0x53/0x100 mm/kmsan/kmsan.c:134
 kmsan_slab_free+0x8d/0x100 mm/kmsan/kmsan_hooks.c:123
 slab_free_freelist_hook mm/slub.c:1472 [inline]
 slab_free mm/slub.c:3038 [inline]
 kmem_cache_free+0x2d1/0x2b70 mm/slub.c:3054
 kfree_skbmem net/core/skbuff.c:644 [inline]
 __kfree_skb+0x1dd/0x210 net/core/skbuff.c:680
 sk_eat_skb include/net/sock.h:2448 [inline]
 tcp_recvmsg+0x27a6/0x4ff0 net/ipv4/tcp.c:2163
 inet_recvmsg+0x237/0x7d0 net/ipv4/af_inet.c:838
 sock_recvmsg_nosec net/socket.c:871 [inline]
 sock_recvmsg net/socket.c:889 [inline]
 sock_read_iter+0x5be/0x660 net/socket.c:967
 call_read_iter include/linux/fs.h:1864 [inline]
 new_sync_read fs/read_write.c:414 [inline]
 __vfs_read+0xa67/0xc90 fs/read_write.c:427
 vfs_read+0x359/0x6f0 fs/read_write.c:461
 ksys_read+0x265/0x430 fs/read_write.c:587
 __do_sys_read fs/read_write.c:597 [inline]
 __se_sys_read+0x92/0xb0 fs/read_write.c:595
 __x64_sys_read+0x4a/0x70 fs/read_write.c:595
 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:297
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
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