syzbot

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BUG: KMSAN: uninit-value in tcp_ack_update_window net/ipv4/tcp_input.c:3324 [inline]
BUG: KMSAN: uninit-value in tcp_ack+0x6eb3/0x8800 net/ipv4/tcp_input.c:3579
CPU: 1 PID: 6879 Comm: syz-executor7 Not tainted 4.16.0+ #87
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __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_ack_update_window net/ipv4/tcp_input.c:3324 [inline]
 tcp_ack+0x6eb3/0x8800 net/ipv4/tcp_input.c:3579
 tcp_rcv_established+0xfc1/0x2bb0 net/ipv4/tcp_input.c:5457
 tcp_v4_do_rcv+0x6cd/0xd90 net/ipv4/tcp_ipv4.c:1469
 sk_backlog_rcv include/net/sock.h:908 [inline]
 __release_sock+0x2d6/0x680 net/core/sock.c:2271
 __sk_flush_backlog+0x52/0x70 net/core/sock.c:2291
 sk_flush_backlog include/net/sock.h:995 [inline]
 tcp_sendmsg_locked+0xcbc/0x6cf0 net/ipv4/tcp.c:1295
 tcp_sendmsg+0xb2/0x100 net/ipv4/tcp.c:1463
 inet_sendmsg+0x48d/0x740 net/ipv4/af_inet.c:764
 sock_sendmsg_nosec net/socket.c:630 [inline]
 sock_sendmsg net/socket.c:640 [inline]
 SYSC_sendto+0x6c3/0x7e0 net/socket.c:1747
 SyS_sendto+0x8a/0xb0 net/socket.c:1715
 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x3d/0xa2
RIP: 0033:0x455389
RSP: 002b:00007fd13dda4c68 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007fd13dda56d4 RCX: 0000000000455389
RDX: 000000000000fda0 RSI: 0000000020fd0000 RDI: 0000000000000013
RBP: 000000000072bea0 R08: 0000000020000080 R09: 0000000000000010
R10: 0000000020000800 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000500 R14: 00000000006fa8a0 R15: 0000000000000000

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:278 [inline]
 kmsan_save_stack mm/kmsan/kmsan.c:293 [inline]
 kmsan_internal_chain_origin+0x12b/0x210 mm/kmsan/kmsan.c:684
 kmsan_memcpy_origins+0x11d/0x170 mm/kmsan/kmsan.c:526
 __msan_memcpy+0x109/0x160 mm/kmsan/kmsan_instr.c:477
 pskb_expand_head+0x3a6/0x1a70 net/core/skbuff.c:1467
 ___pskb_trim+0x2e8/0x1ae0 net/core/skbuff.c:1769
 __pskb_trim include/linux/skbuff.h:2484 [inline]
 pskb_trim include/linux/skbuff.h:2491 [inline]
 sk_filter_trim_cap+0x50f/0xa00 net/core/filter.c:105
 tcp_filter net/ipv4/tcp_ipv4.c:1586 [inline]
 tcp_v4_rcv+0x510f/0x6af0 net/ipv4/tcp_ipv4.c:1727
 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
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_fclone include/linux/skbuff.h:1026 [inline]
 sk_stream_alloc_skb+0x17c/0xcf0 net/ipv4/tcp.c:866
 tso_fragment net/ipv4/tcp_output.c:1881 [inline]
 tcp_write_xmit+0x1d78/0xb920 net/ipv4/tcp_output.c:2385
 __tcp_push_pending_frames+0x124/0x3f0 net/ipv4/tcp_output.c:2567
 tcp_push_pending_frames include/net/tcp.h:1682 [inline]
 tcp_data_snd_check+0x184/0xe30 net/ipv4/tcp_input.c:5018
 tcp_rcv_established+0x1977/0x2bb0 net/ipv4/tcp_input.c:5468
 tcp_v4_do_rcv+0x6cd/0xd90 net/ipv4/tcp_ipv4.c:1469
 sk_backlog_rcv include/net/sock.h:908 [inline]
 __release_sock+0x2d6/0x680 net/core/sock.c:2271
 __sk_flush_backlog+0x52/0x70 net/core/sock.c:2291
 sk_flush_backlog include/net/sock.h:995 [inline]
 tcp_sendmsg_locked+0xcbc/0x6cf0 net/ipv4/tcp.c:1295
 tcp_sendmsg+0xb2/0x100 net/ipv4/tcp.c:1463
 inet_sendmsg+0x48d/0x740 net/ipv4/af_inet.c:764
 sock_sendmsg_nosec net/socket.c:630 [inline]
 sock_sendmsg net/socket.c:640 [inline]
 SYSC_sendto+0x6c3/0x7e0 net/socket.c:1747
 SyS_sendto+0x8a/0xb0 net/socket.c:1715
 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x3d/0xa2
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