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BUG: KMSAN: uninit-value in tcp_parse_options+0x1161/0x1c70 net/ipv4/tcp_input.c:3720
CPU: 1 PID: 2564 Comm: udevd Not tainted 4.16.0+ #87
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x185/0x1d0 lib/dump_stack.c:53
 kmsan_report+0x142/0x240 mm/kmsan/kmsan.c:1067
 __msan_warning_32+0x6c/0xb0 mm/kmsan/kmsan_instr.c:683
 tcp_parse_options+0x1161/0x1c70 net/ipv4/tcp_input.c:3720
 tcp_fast_parse_options net/ipv4/tcp_input.c:3858 [inline]
 tcp_validate_incoming+0x4f1/0x2790 net/ipv4/tcp_input.c:5184
 tcp_rcv_established+0xf60/0x2bb0 net/ipv4/tcp_input.c:5453
 tcp_v4_do_rcv+0x6cd/0xd90 net/ipv4/tcp_ipv4.c:1469
 tcp_v4_rcv+0x5ecf/0x6af0 net/ipv4/tcp_ipv4.c:1746
 ip_local_deliver_finish+0x874/0xec0 net/ipv4/ip_input.c:216
 NF_HOOK include/linux/netfilter.h:288 [inline]
 ip_local_deliver+0x43c/0x4e0 net/ipv4/ip_input.c:257
 dst_input include/net/dst.h:449 [inline]
 ip_rcv_finish+0xa36/0x1d00 net/ipv4/ip_input.c:397
 NF_HOOK include/linux/netfilter.h:288 [inline]
 ip_rcv+0x118f/0x16d0 net/ipv4/ip_input.c:493
 __netif_receive_skb_core+0x47df/0x4a90 net/core/dev.c:4562
 __netif_receive_skb net/core/dev.c:4627 [inline]
 process_backlog+0x62d/0xe20 net/core/dev.c:5307
 napi_poll net/core/dev.c:5705 [inline]
 net_rx_action+0x7c1/0x1a70 net/core/dev.c:5771
 __do_softirq+0x56d/0x93d kernel/softirq.c:285
 invoke_softirq kernel/softirq.c:365 [inline]
 irq_exit+0x202/0x240 kernel/softirq.c:405
 exiting_irq+0xe/0x10 arch/x86/include/asm/apic.h:541
 smp_apic_timer_interrupt+0x64/0x90 arch/x86/kernel/apic/apic.c:1055
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:857
 </IRQ>
RIP: 0010:native_restore_fl arch/x86/include/asm/irqflags.h:37 [inline]
RIP: 0010:arch_local_irq_restore arch/x86/include/asm/irqflags.h:78 [inline]
RIP: 0010:kmsan_kmalloc+0xc6/0x100 mm/kmsan/kmsan.c:316
RSP: 0018:ffff88019fecfb20 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff12
RAX: 0000000000000246 RBX: ffff88019cd2e000 RCX: 0000000000000401
RDX: 0000000000000400 RSI: ffffea0009acf188 RDI: ffff88019cd2e000
RBP: ffff88019fecfb60 R08: 00000000010000c0 R09: 0000000000000002
R10: 0000000000000000 R11: ffff88019fec0000 R12: ffff8801dc308d80
R13: ffff88019fea0000 R14: 0000000000001000 R15: 00000000014000c0
 kmsan_slab_alloc+0x11/0x20 mm/kmsan/kmsan.c:321
 slab_post_alloc_hook mm/slab.h:445 [inline]
 slab_alloc_node mm/slub.c:2737 [inline]
 slab_alloc mm/slub.c:2745 [inline]
 kmem_cache_alloc+0x692/0xb90 mm/slub.c:2750
 getname_flags+0x12a/0xaa0 fs/namei.c:138
 user_path_at_empty+0xbb/0x140 fs/namei.c:2569
 user_path_at include/linux/namei.h:57 [inline]
 vfs_statx fs/stat.c:185 [inline]
 vfs_stat include/linux/fs.h:3075 [inline]
 SYSC_newstat+0xd4/0x330 fs/stat.c:337
 SyS_newstat+0x46/0x70 fs/stat.c:333
 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x3d/0xa2
RIP: 0033:0x7f242feaac65
RSP: 002b:00007ffc86cd2aa8 EFLAGS: 00000246 ORIG_RAX: 0000000000000004
RAX: ffffffffffffffda RBX: 000000000180b250 RCX: 00007f242feaac65
RDX: 00007ffc86cd2ac0 RSI: 00007ffc86cd2ac0 RDI: 00007ffc86cd2f50
RBP: 00007ffc86cd3390 R08: 000000000041f4f1 R09: 00007f242ff017d0
R10: 7665642f7379732f R11: 0000000000000246 R12: 0000000000000004
R13: 00007ffc86cd3397 R14: 000000000180b250 R15: 0000000001810e10

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:278 [inline]
 kmsan_internal_poison_shadow+0xb8/0x1b0 mm/kmsan/kmsan.c:188
 kmsan_kmalloc+0x94/0x100 mm/kmsan/kmsan.c:314
 kmsan_slab_alloc+0x11/0x20 mm/kmsan/kmsan.c:321
 slab_post_alloc_hook mm/slab.h:445 [inline]
 slab_alloc_node mm/slub.c:2737 [inline]
 __kmalloc_node_track_caller+0xaed/0x11c0 mm/slub.c:4369
 __kmalloc_reserve net/core/skbuff.c:138 [inline]
 __alloc_skb+0x2cf/0x9f0 net/core/skbuff.c:206
 alloc_skb include/linux/skbuff.h:984 [inline]
 tcp_send_ack+0x18c/0x910 net/ipv4/tcp_output.c:3624
 __tcp_ack_snd_check net/ipv4/tcp_input.c:5040 [inline]
 tcp_ack_snd_check net/ipv4/tcp_input.c:5053 [inline]
 tcp_rcv_established+0x2103/0x2bb0 net/ipv4/tcp_input.c:5469
 tcp_v4_do_rcv+0x6cd/0xd90 net/ipv4/tcp_ipv4.c:1469
 tcp_v4_rcv+0x5ecf/0x6af0 net/ipv4/tcp_ipv4.c:1746
 ip_local_deliver_finish+0x874/0xec0 net/ipv4/ip_input.c:216
 NF_HOOK include/linux/netfilter.h:288 [inline]
 ip_local_deliver+0x43c/0x4e0 net/ipv4/ip_input.c:257
 dst_input include/net/dst.h:449 [inline]
 ip_rcv_finish+0xa36/0x1d00 net/ipv4/ip_input.c:397
 NF_HOOK include/linux/netfilter.h:288 [inline]
 ip_rcv+0x118f/0x16d0 net/ipv4/ip_input.c:493
 __netif_receive_skb_core+0x47df/0x4a90 net/core/dev.c:4562
 __netif_receive_skb net/core/dev.c:4627 [inline]
 process_backlog+0x62d/0xe20 net/core/dev.c:5307
 napi_poll net/core/dev.c:5705 [inline]
 net_rx_action+0x7c1/0x1a70 net/core/dev.c:5771
 __do_softirq+0x56d/0x93d kernel/softirq.c:285
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