================================================================== BUG: KMSAN: uninit-value in __arch_swab32 arch/x86/include/uapi/asm/swab.h:10 [inline] BUG: KMSAN: uninit-value in __fswab32 include/uapi/linux/swab.h:59 [inline] BUG: KMSAN: uninit-value in erspan_rcv net/ipv4/ip_gre.c:282 [inline] BUG: KMSAN: uninit-value in gre_rcv+0x11a3/0x1900 net/ipv4/ip_gre.c:422 CPU: 0 PID: 17464 Comm: syz-executor4 Not tainted 4.20.0-rc3+ #94 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+0x32d/0x480 lib/dump_stack.c:113 kmsan_report+0x12c/0x290 mm/kmsan/kmsan.c:765 __msan_warning+0x76/0xc0 mm/kmsan/kmsan_instr.c:410 __arch_swab32 arch/x86/include/uapi/asm/swab.h:10 [inline] __fswab32 include/uapi/linux/swab.h:59 [inline] erspan_rcv net/ipv4/ip_gre.c:282 [inline] gre_rcv+0x11a3/0x1900 net/ipv4/ip_gre.c:422 gre_rcv+0x2e6/0x3c0 net/ipv4/gre_demux.c:143 ip_local_deliver_finish+0x8d8/0xff0 net/ipv4/ip_input.c:215 NF_HOOK include/linux/netfilter.h:289 [inline] ip_local_deliver+0x44b/0x510 net/ipv4/ip_input.c:256 dst_input include/net/dst.h:450 [inline] ip_rcv_finish net/ipv4/ip_input.c:415 [inline] NF_HOOK include/linux/netfilter.h:289 [inline] ip_rcv+0x6b6/0x740 net/ipv4/ip_input.c:524 __netif_receive_skb_one_core net/core/dev.c:4941 [inline] __netif_receive_skb net/core/dev.c:5051 [inline] process_backlog+0x82b/0x11e0 net/core/dev.c:5855 napi_poll net/core/dev.c:6275 [inline] net_rx_action+0x98f/0x1d50 net/core/dev.c:6341 __do_softirq+0x721/0xc7f kernel/softirq.c:292 do_softirq_own_stack+0x49/0x80 arch/x86/entry/entry_64.S:1031 do_softirq kernel/softirq.c:337 [inline] __local_bh_enable_ip+0x228/0x260 kernel/softirq.c:189 local_bh_enable+0x36/0x40 include/linux/bottom_half.h:32 rcu_read_unlock_bh include/linux/rcupdate.h:696 [inline] ip_finish_output2+0x1430/0x1560 net/ipv4/ip_output.c:231 ip_finish_output+0xd93/0x10f0 net/ipv4/ip_output.c:317 NF_HOOK_COND include/linux/netfilter.h:278 [inline] ip_output+0x55c/0x630 net/ipv4/ip_output.c:405 dst_output include/net/dst.h:444 [inline] ip_local_out net/ipv4/ip_output.c:124 [inline] ip_send_skb+0x178/0x370 net/ipv4/ip_output.c:1441 udp_send_skb+0x1439/0x1920 net/ipv4/udp.c:829 udp_push_pending_frames net/ipv4/udp.c:857 [inline] udp_sendmsg+0x1496/0x4350 net/ipv4/udp.c:1148 kvm [17455]: vcpu0, guest rIP: 0x90c2 Hyper-V uhandled wrmsr: 0x40000011 data 0x0 udpv6_sendmsg+0x123e/0x4960 net/ipv6/udp.c:1203 kvm [17455]: vcpu0, guest rIP: 0x90c2 Hyper-V uhandled wrmsr: 0x40000012 data 0x0 inet_sendmsg+0x4e9/0x800 net/ipv4/af_inet.c:798 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg net/socket.c:631 [inline] __sys_sendto+0x940/0xb80 net/socket.c:1788 kvm [17455]: vcpu0, guest rIP: 0x90c2 Hyper-V uhandled wrmsr: 0x40000013 data 0x0 __do_sys_sendto net/socket.c:1800 [inline] __se_sys_sendto+0x107/0x130 net/socket.c:1796 __x64_sys_sendto+0x6e/0x90 net/socket.c:1796 do_syscall_64+0xcf/0x110 arch/x86/entry/common.c:291 entry_SYSCALL_64_after_hwframe+0x63/0xe7 RIP: 0033:0x457569 Code: fd b3 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 b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f8e91e0ac78 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 0000000000457569 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 000000000072bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f8e91e0b6d4 R13: 00000000004c407b R14: 00000000004d6910 R15: 00000000ffffffff kvm [17455]: vcpu0, guest rIP: 0x90c2 Hyper-V uhandled wrmsr: 0x40000014 data 0x0 Uninit was stored to memory at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:246 [inline] kmsan_save_stack mm/kmsan/kmsan.c:261 [inline] kmsan_internal_chain_origin+0x13d/0x240 mm/kmsan/kmsan.c:469 kmsan_memcpy_memmove_metadata+0x1a9/0xf70 mm/kmsan/kmsan.c:344 kmsan_memcpy_metadata+0xb/0x10 mm/kmsan/kmsan.c:362 __msan_memcpy+0x61/0x70 mm/kmsan/kmsan_instr.c:236 pskb_expand_head+0x436/0x1d20 net/core/skbuff.c:1470 __skb_cow include/linux/skbuff.h:2948 [inline] skb_cow_head include/linux/skbuff.h:2982 [inline] ip_tunnel_xmit+0x35a3/0x3d90 net/ipv4/ip_tunnel.c:780 __gre_xmit net/ipv4/ip_gre.c:451 [inline] erspan_xmit+0x1bce/0x35d0 net/ipv4/ip_gre.c:749 __netdev_start_xmit include/linux/netdevice.h:4356 [inline] netdev_start_xmit include/linux/netdevice.h:4365 [inline] xmit_one net/core/dev.c:3252 [inline] dev_hard_start_xmit+0x6dc/0xde0 net/core/dev.c:3268 sch_direct_xmit+0x59b/0x890 net/sched/sch_generic.c:327 qdisc_restart net/sched/sch_generic.c:390 [inline] __qdisc_run+0x1bac/0x3600 net/sched/sch_generic.c:398 qdisc_run include/net/pkt_sched.h:121 [inline] __dev_xmit_skb net/core/dev.c:3447 [inline] __dev_queue_xmit+0x2131/0x3e00 net/core/dev.c:3806 dev_queue_xmit+0x4b/0x60 net/core/dev.c:3871 neigh_resolve_output+0xab7/0xb50 net/core/neighbour.c:1382 neigh_output include/net/neighbour.h:484 [inline] ip_finish_output2+0x141a/0x1560 net/ipv4/ip_output.c:229 ip_finish_output+0xd93/0x10f0 net/ipv4/ip_output.c:317 NF_HOOK_COND include/linux/netfilter.h:278 [inline] ip_output+0x55c/0x630 net/ipv4/ip_output.c:405 dst_output include/net/dst.h:444 [inline] ip_local_out net/ipv4/ip_output.c:124 [inline] ip_send_skb+0x178/0x370 net/ipv4/ip_output.c:1441 udp_send_skb+0x1439/0x1920 net/ipv4/udp.c:829 udp_push_pending_frames net/ipv4/udp.c:857 [inline] udp_sendmsg+0x1496/0x4350 net/ipv4/udp.c:1148 udpv6_sendmsg+0x123e/0x4960 net/ipv6/udp.c:1203 inet_sendmsg+0x4e9/0x800 net/ipv4/af_inet.c:798 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg net/socket.c:631 [inline] __sys_sendto+0x940/0xb80 net/socket.c:1788 __do_sys_sendto net/socket.c:1800 [inline] __se_sys_sendto+0x107/0x130 net/socket.c:1796 __x64_sys_sendto+0x6e/0x90 net/socket.c:1796 do_syscall_64+0xcf/0x110 arch/x86/entry/common.c:291 entry_SYSCALL_64_after_hwframe+0x63/0xe7 Uninit was created at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:246 [inline] kmsan_internal_poison_shadow+0x6d/0x130 mm/kmsan/kmsan.c:170 kmsan_kmalloc+0xa1/0x100 mm/kmsan/kmsan_hooks.c:104 kmsan_slab_alloc+0xe/0x10 mm/kmsan/kmsan_hooks.c:113 slab_post_alloc_hook mm/slab.h:446 [inline] slab_alloc_node mm/slub.c:2765 [inline] __kmalloc_node_track_caller+0xf62/0x14e0 mm/slub.c:4396 __kmalloc_reserve net/core/skbuff.c:138 [inline] __alloc_skb+0x42b/0xeb0 net/core/skbuff.c:206 alloc_skb include/linux/skbuff.h:998 [inline] alloc_skb_with_frags+0x1c9/0xa80 net/core/skbuff.c:5220 sock_alloc_send_pskb+0xeb3/0x14c0 net/core/sock.c:2083 sock_alloc_send_skb+0xca/0xe0 net/core/sock.c:2100 __ip_append_data+0x2bd2/0x4460 net/ipv4/ip_output.c:981 ip_append_data+0x30c/0x450 net/ipv4/ip_output.c:1196 udp_sendmsg+0x74e/0x4350 net/ipv4/udp.c:1142 udpv6_sendmsg+0x123e/0x4960 net/ipv6/udp.c:1203 inet_sendmsg+0x4e9/0x800 net/ipv4/af_inet.c:798 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg net/socket.c:631 [inline] __sys_sendto+0x940/0xb80 net/socket.c:1788 __do_sys_sendto net/socket.c:1800 [inline] __se_sys_sendto+0x107/0x130 net/socket.c:1796 __x64_sys_sendto+0x6e/0x90 net/socket.c:1796 do_syscall_64+0xcf/0x110 arch/x86/entry/common.c:291 entry_SYSCALL_64_after_hwframe+0x63/0xe7 ==================================================================