=====================================================
BUG: KMSAN: uninit-value in eth_skb_pkt_type include/linux/etherdevice.h:628 [inline]
BUG: KMSAN: uninit-value in eth_type_trans+0x7af/0x9a0 net/ethernet/eth.c:165
 eth_skb_pkt_type include/linux/etherdevice.h:628 [inline]
 eth_type_trans+0x7af/0x9a0 net/ethernet/eth.c:165
 ip_tunnel_rcv+0x2d7d/0x34f0 net/ipv4/ip_tunnel.c:439
 erspan_rcv net/ipv4/ip_gre.c:354 [inline]
 gre_rcv+0x1aad/0x2050 net/ipv4/ip_gre.c:458
 gre_rcv+0x285/0x380 net/ipv4/gre_demux.c:163
 ip_protocol_deliver_rcu+0xb2c/0x13d0 net/ipv4/ip_input.c:205
 ip_local_deliver_finish+0x409/0x730 net/ipv4/ip_input.c:239
 NF_HOOK include/linux/netfilter.h:318 [inline]
 ip_local_deliver+0x228/0x4b0 net/ipv4/ip_input.c:260
 dst_input include/net/dst.h:471 [inline]
 ip_rcv_finish+0x4f7/0x5c0 net/ipv4/ip_input.c:454
 NF_HOOK include/linux/netfilter.h:318 [inline]
 ip_rcv+0xcb/0x380 net/ipv4/ip_input.c:574
 __netif_receive_skb_one_core net/core/dev.c:5991 [inline]
 __netif_receive_skb+0x312/0xac0 net/core/dev.c:6104
 process_backlog+0x485/0xa00 net/core/dev.c:6456
 __napi_poll+0xdd/0x8a0 net/core/dev.c:7506
 napi_poll net/core/dev.c:7569 [inline]
 net_rx_action+0xa59/0x1ac0 net/core/dev.c:7696
 handle_softirqs+0x166/0x6e0 kernel/softirq.c:579
 __do_softirq kernel/softirq.c:613 [inline]
 invoke_softirq kernel/softirq.c:453 [inline]
 __irq_exit_rcu+0x66/0x180 kernel/softirq.c:680
 irq_exit_rcu+0x12/0x20 kernel/softirq.c:696
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
 sysvec_apic_timer_interrupt+0x84/0x90 arch/x86/kernel/apic/apic.c:1050
 asm_sysvec_apic_timer_interrupt+0x1f/0x30 arch/x86/include/asm/idtentry.h:702
 virt_to_page_or_null+0x0/0x180 mm/kmsan/shadow.c:59
 kmsan_get_shadow_origin_ptr+0x35/0xb0 mm/kmsan/shadow.c:97
 get_shadow_origin_ptr mm/kmsan/instrumentation.c:38 [inline]
 __msan_metadata_ptr_for_load_8+0x24/0x40 mm/kmsan/instrumentation.c:94
 unwind_get_return_address_ptr+0x46/0xd0 arch/x86/kernel/unwind_frame.c:28
 update_stack_state+0x174/0x1c0 arch/x86/kernel/unwind_frame.c:251
 unwind_next_frame+0x116/0x350 arch/x86/kernel/unwind_frame.c:315
 arch_stack_walk+0x1b1/0x280 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0xc3/0x100 kernel/stacktrace.c:122
 kmsan_save_stack_with_flags mm/kmsan/core.c:73 [inline]
 kmsan_internal_poison_memory+0x4a/0xa0 mm/kmsan/core.c:57
 kmsan_slab_free+0xd0/0x140 mm/kmsan/hooks.c:87
 slab_free_hook mm/slub.c:2343 [inline]
 slab_free mm/slub.c:4680 [inline]
 kmem_cache_free+0x2a1/0xec0 mm/slub.c:4782
 kfree_skbmem net/core/skbuff.c:-1 [inline]
 __kfree_skb+0x20b/0x260 net/core/skbuff.c:1166
 consume_skb+0x83/0x230 net/core/skbuff.c:1397
 nsim_dev_trap_report drivers/net/netdevsim/dev.c:836 [inline]
 nsim_dev_trap_report_work+0x1063/0x1440 drivers/net/netdevsim/dev.c:866
 process_one_work kernel/workqueue.c:3236 [inline]
 process_scheduled_works+0xb8e/0x1d80 kernel/workqueue.c:3319
 worker_thread+0xedf/0x1590 kernel/workqueue.c:3400
 kthread+0xd59/0xf00 kernel/kthread.c:463
 ret_from_fork+0x1e3/0x310 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Uninit was created at:
 slab_post_alloc_hook mm/slub.c:4186 [inline]
 slab_alloc_node mm/slub.c:4229 [inline]
 kmem_cache_alloc_node_noprof+0x818/0xf00 mm/slub.c:4281
 kmalloc_reserve+0x13c/0x4b0 net/core/skbuff.c:578
 __alloc_skb+0x347/0x7d0 net/core/skbuff.c:669
 alloc_skb_fclone include/linux/skbuff.h:1386 [inline]
 tcp_stream_alloc_skb+0x4c/0x5f0 net/ipv4/tcp.c:892
 tcp_sendmsg_locked+0x1db5/0x7680 net/ipv4/tcp.c:1198
 tcp_sendmsg+0x4b/0x90 net/ipv4/tcp.c:1393
 inet_sendmsg+0x134/0x2a0 net/ipv4/af_inet.c:851
 sock_sendmsg_nosec net/socket.c:714 [inline]
 __sock_sendmsg+0x278/0x3d0 net/socket.c:729
 ____sys_sendmsg+0x7e0/0xd80 net/socket.c:2614
 ___sys_sendmsg+0x271/0x3b0 net/socket.c:2668
 __sys_sendmsg net/socket.c:2700 [inline]
 __do_sys_sendmsg net/socket.c:2705 [inline]
 __se_sys_sendmsg net/socket.c:2703 [inline]
 __x64_sys_sendmsg+0x211/0x3e0 net/socket.c:2703
 x64_sys_call+0x1dfd/0x3e20 arch/x86/include/generated/asm/syscalls_64.h:47
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd9/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

CPU: 0 UID: 0 PID: 4415 Comm: kworker/u8:21 Not tainted syzkaller #0 PREEMPT(none) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Workqueue: events_unbound nsim_dev_trap_report_work
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