================================================================== BUG: KMSAN: uninit-value in dccp_invalid_packet+0x3b8/0xf50 net/dccp/ipv4.c:716 CPU: 1 PID: 7234 Comm: syz-executor6 Not tainted 4.16.0+ #81 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:676 dccp_invalid_packet+0x3b8/0xf50 net/dccp/ipv4.c:716 dccp_v6_rcv+0xe0/0x2340 net/dccp/ipv6.c:690 ip6_input_finish+0xa62/0x2110 net/ipv6/ip6_input.c:284 NF_HOOK include/linux/netfilter.h:288 [inline] ip6_input+0x294/0x320 net/ipv6/ip6_input.c:327 dst_input include/net/dst.h:449 [inline] ip6_rcv_finish net/ipv6/ip6_input.c:71 [inline] NF_HOOK include/linux/netfilter.h:288 [inline] ipv6_rcv+0x20ec/0x26d0 net/ipv6/ip6_input.c:208 __netif_receive_skb_core+0x47cf/0x4a80 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 do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1040 do_softirq kernel/softirq.c:329 [inline] __local_bh_enable_ip+0x114/0x140 kernel/softirq.c:182 local_bh_enable+0x36/0x40 include/linux/bottom_half.h:32 rcu_read_unlock_bh include/linux/rcupdate.h:726 [inline] ip6_finish_output2+0x1b6c/0x1f20 net/ipv6/ip6_output.c:121 ip6_finish_output+0xb3f/0xc00 net/ipv6/ip6_output.c:154 NF_HOOK_COND include/linux/netfilter.h:277 [inline] ip6_output+0x597/0x6c0 net/ipv6/ip6_output.c:171 dst_output include/net/dst.h:443 [inline] ip6_local_out+0x573/0x640 net/ipv6/output_core.c:176 ip6_send_skb net/ipv6/ip6_output.c:1682 [inline] ip6_push_pending_frames+0x218/0x4d0 net/ipv6/ip6_output.c:1702 rawv6_push_pending_frames net/ipv6/raw.c:616 [inline] rawv6_sendmsg+0x4500/0x4cc0 net/ipv6/raw.c:935 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] sock_write_iter+0x3b9/0x470 net/socket.c:909 call_write_iter include/linux/fs.h:1782 [inline] new_sync_write fs/read_write.c:469 [inline] __vfs_write+0x719/0x910 fs/read_write.c:482 vfs_write+0x463/0x8d0 fs/read_write.c:544 SYSC_write+0x172/0x360 fs/read_write.c:589 SyS_write+0x55/0x80 fs/read_write.c:581 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x3d/0xa2 RIP: 0033:0x455259 RSP: 002b:00007f03cb2d1c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f03cb2d26d4 RCX: 0000000000455259 RDX: 0000000000000050 RSI: 0000000020000000 RDI: 0000000000000013 RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000006b6 R14: 00000000006fd1b0 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+0x19f/0x1f0 mm/kmsan/kmsan_instr.c:470 skb_copy_bits+0x63a/0xdb0 net/core/skbuff.c:2046 __pskb_pull_tail+0x483/0x22e0 net/core/skbuff.c:1883 pskb_may_pull include/linux/skbuff.h:2112 [inline] dccp_invalid_packet+0x352/0xf50 net/dccp/ipv4.c:708 dccp_v6_rcv+0xe0/0x2340 net/dccp/ipv6.c:690 ip6_input_finish+0xa62/0x2110 net/ipv6/ip6_input.c:284 NF_HOOK include/linux/netfilter.h:288 [inline] ip6_input+0x294/0x320 net/ipv6/ip6_input.c:327 dst_input include/net/dst.h:449 [inline] ip6_rcv_finish net/ipv6/ip6_input.c:71 [inline] NF_HOOK include/linux/netfilter.h:288 [inline] ipv6_rcv+0x20ec/0x26d0 net/ipv6/ip6_input.c:208 __netif_receive_skb_core+0x47cf/0x4a80 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_alloc_meta_for_pages+0x161/0x3a0 mm/kmsan/kmsan.c:814 kmsan_alloc_page+0x82/0xe0 mm/kmsan/kmsan.c:868 __alloc_pages_nodemask+0xf5b/0x5dc0 mm/page_alloc.c:4283 alloc_pages_current+0x6b5/0x970 mm/mempolicy.c:2055 alloc_pages include/linux/gfp.h:494 [inline] skb_page_frag_refill+0x3ba/0x5e0 net/core/sock.c:2208 sk_page_frag_refill+0xa4/0x340 net/core/sock.c:2228 __ip6_append_data+0x1a20/0x4bb0 net/ipv6/ip6_output.c:1503 ip6_append_data+0x40e/0x6b0 net/ipv6/ip6_output.c:1576 rawv6_sendmsg+0x2787/0x4cc0 net/ipv6/raw.c:928 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] sock_write_iter+0x3b9/0x470 net/socket.c:909 call_write_iter include/linux/fs.h:1782 [inline] new_sync_write fs/read_write.c:469 [inline] __vfs_write+0x719/0x910 fs/read_write.c:482 vfs_write+0x463/0x8d0 fs/read_write.c:544 SYSC_write+0x172/0x360 fs/read_write.c:589 SyS_write+0x55/0x80 fs/read_write.c:581 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x3d/0xa2 ==================================================================