================================================================== 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+0x1237/0x1970 net/ipv4/ip_gre.c:420 CPU: 1 PID: 11977 Comm: syz-executor5 Not tainted 4.17.0-rc5+ #102 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+0x185/0x1d0 lib/dump_stack.c:113 kmsan_report+0x149/0x260 mm/kmsan/kmsan.c:1084 __msan_warning_32+0x6e/0xc0 mm/kmsan/kmsan_instr.c:686 __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+0x1237/0x1970 net/ipv4/ip_gre.c:420 gre_rcv+0x2d6/0x3b0 net/ipv4/gre_demux.c:142 ip_local_deliver_finish+0x881/0xed0 net/ipv4/ip_input.c:215 NF_HOOK include/linux/netfilter.h:288 [inline] ip_local_deliver+0x43c/0x4e0 net/ipv4/ip_input.c:256 dst_input include/net/dst.h:450 [inline] ip_rcv_finish+0xa36/0x1d00 net/ipv4/ip_input.c:396 NF_HOOK include/linux/netfilter.h:288 [inline] ip_rcv+0x118a/0x16d0 net/ipv4/ip_input.c:492 __netif_receive_skb_core+0x47ff/0x4ac0 net/core/dev.c:4592 __netif_receive_skb net/core/dev.c:4657 [inline] process_backlog+0x62d/0xe20 net/core/dev.c:5337 napi_poll net/core/dev.c:5735 [inline] net_rx_action+0x7c1/0x1a70 net/core/dev.c:5801 __do_softirq+0x56d/0x93d kernel/softirq.c:285 do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1046 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:728 [inline] ip_finish_output2+0x1378/0x1490 net/ipv4/ip_output.c:231 ip_finish_output+0xcaf/0xff0 net/ipv4/ip_output.c:317 NF_HOOK_COND include/linux/netfilter.h:277 [inline] ip_output+0x505/0x5d0 net/ipv4/ip_output.c:405 dst_output include/net/dst.h:444 [inline] NF_HOOK include/linux/netfilter.h:288 [inline] raw_send_hdrinc net/ipv4/raw.c:432 [inline] raw_sendmsg+0x3e77/0x41c0 net/ipv4/raw.c:669 inet_sendmsg+0x3f7/0x750 net/ipv4/af_inet.c:798 sock_sendmsg_nosec net/socket.c:629 [inline] sock_sendmsg net/socket.c:639 [inline] __sys_sendto+0x6c0/0x7e0 net/socket.c:1789 __do_sys_sendto net/socket.c:1801 [inline] __se_sys_sendto net/socket.c:1797 [inline] __x64_sys_sendto+0x1a1/0x210 net/socket.c:1797 do_syscall_64+0x152/0x230 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x455a09 RSP: 002b:00007f0be8671c68 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007f0be86726d4 RCX: 0000000000455a09 RDX: 00000000000002e2 RSI: 00000000200002c0 RDI: 0000000000000013 RBP: 000000000072bea0 R08: 0000000020000040 R09: 0000000000000010 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000005ab R14: 00000000006fc8a8 R15: 0000000000000000 Uninit was stored to memory at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:279 [inline] kmsan_save_stack mm/kmsan/kmsan.c:294 [inline] kmsan_internal_chain_origin+0x12b/0x210 mm/kmsan/kmsan.c:685 kmsan_memcpy_origins+0x11d/0x170 mm/kmsan/kmsan.c:527 __msan_memcpy+0x109/0x160 mm/kmsan/kmsan_instr.c:478 pskb_expand_head+0x3a6/0x1a70 net/core/skbuff.c:1470 __skb_cow include/linux/skbuff.h:2899 [inline] skb_cow_head include/linux/skbuff.h:2933 [inline] ip_tunnel_xmit+0x2dd6/0x37b0 net/ipv4/ip_tunnel.c:771 __gre_xmit net/ipv4/ip_gre.c:449 [inline] erspan_xmit+0x1c67/0x2d70 net/ipv4/ip_gre.c:731 __netdev_start_xmit include/linux/netdevice.h:4087 [inline] netdev_start_xmit include/linux/netdevice.h:4096 [inline] xmit_one net/core/dev.c:3053 [inline] dev_hard_start_xmit+0x5f1/0xc70 net/core/dev.c:3069 sch_direct_xmit+0x578/0x8f0 net/sched/sch_generic.c:327 qdisc_restart net/sched/sch_generic.c:399 [inline] __qdisc_run+0x1785/0x3730 net/sched/sch_generic.c:410 __dev_xmit_skb net/core/dev.c:3244 [inline] __dev_queue_xmit+0x1d50/0x3510 net/core/dev.c:3552 dev_queue_xmit+0x4b/0x60 net/core/dev.c:3617 neigh_resolve_output+0xac6/0xb60 net/core/neighbour.c:1358 neigh_output include/net/neighbour.h:482 [inline] ip_finish_output2+0x1362/0x1490 net/ipv4/ip_output.c:229 ip_finish_output+0xcaf/0xff0 net/ipv4/ip_output.c:317 NF_HOOK_COND include/linux/netfilter.h:277 [inline] ip_output+0x505/0x5d0 net/ipv4/ip_output.c:405 dst_output include/net/dst.h:444 [inline] NF_HOOK include/linux/netfilter.h:288 [inline] raw_send_hdrinc net/ipv4/raw.c:432 [inline] raw_sendmsg+0x3e77/0x41c0 net/ipv4/raw.c:669 inet_sendmsg+0x3f7/0x750 net/ipv4/af_inet.c:798 sock_sendmsg_nosec net/socket.c:629 [inline] sock_sendmsg net/socket.c:639 [inline] __sys_sendto+0x6c0/0x7e0 net/socket.c:1789 __do_sys_sendto net/socket.c:1801 [inline] __se_sys_sendto net/socket.c:1797 [inline] __x64_sys_sendto+0x1a1/0x210 net/socket.c:1797 do_syscall_64+0x152/0x230 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Uninit was created at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:279 [inline] kmsan_internal_poison_shadow+0xb8/0x1b0 mm/kmsan/kmsan.c:189 kmsan_kmalloc+0x94/0x100 mm/kmsan/kmsan.c:315 kmsan_slab_alloc+0x10/0x20 mm/kmsan/kmsan.c:322 slab_post_alloc_hook mm/slab.h:446 [inline] slab_alloc_node mm/slub.c:2753 [inline] __kmalloc_node_track_caller+0xb32/0x11b0 mm/slub.c:4395 __kmalloc_reserve net/core/skbuff.c:138 [inline] __alloc_skb+0x2cb/0x9e0 net/core/skbuff.c:206 alloc_skb include/linux/skbuff.h:988 [inline] alloc_skb_with_frags+0x1e6/0xb80 net/core/skbuff.c:5254 sock_alloc_send_pskb+0xb56/0x1190 net/core/sock.c:2088 sock_alloc_send_skb+0xca/0xe0 net/core/sock.c:2105 raw_send_hdrinc net/ipv4/raw.c:375 [inline] raw_sendmsg+0x221c/0x41c0 net/ipv4/raw.c:669 inet_sendmsg+0x3f7/0x750 net/ipv4/af_inet.c:798 sock_sendmsg_nosec net/socket.c:629 [inline] sock_sendmsg net/socket.c:639 [inline] __sys_sendto+0x6c0/0x7e0 net/socket.c:1789 __do_sys_sendto net/socket.c:1801 [inline] __se_sys_sendto net/socket.c:1797 [inline] __x64_sys_sendto+0x1a1/0x210 net/socket.c:1797 do_syscall_64+0x152/0x230 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x44/0xa9 ==================================================================