===================================================== BUG: KMSAN: uninit-value in __netif_receive_skb_core+0x3f45/0x6520 net/core/dev.c:5197 CPU: 1 PID: 3028 Comm: syz-executor.5 Not tainted 5.8.0-rc5-syzkaller #0 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+0x21c/0x280 lib/dump_stack.c:118 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:121 __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:215 __netif_receive_skb_core+0x3f45/0x6520 net/core/dev.c:5197 __netif_receive_skb_one_core net/core/dev.c:5279 [inline] __netif_receive_skb+0x164/0x670 net/core/dev.c:5395 process_backlog+0x50d/0xba0 net/core/dev.c:6239 napi_poll+0x43b/0xfd0 net/core/dev.c:6684 net_rx_action+0x35c/0xd40 net/core/dev.c:6752 __do_softirq+0x2ea/0x7f5 kernel/softirq.c:293 asm_call_on_stack+0xf/0x20 arch/x86/entry/entry_64.S:711 __run_on_irqstack arch/x86/include/asm/irq_stack.h:23 [inline] run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:50 [inline] do_softirq_own_stack+0x7c/0xa0 arch/x86/kernel/irq_64.c:77 do_softirq kernel/softirq.c:338 [inline] __local_bh_enable_ip+0x184/0x1d0 kernel/softirq.c:190 local_bh_enable+0x36/0x40 include/linux/bottom_half.h:32 rcu_read_unlock_bh include/linux/rcupdate.h:723 [inline] __dev_queue_xmit+0x41a8/0x4470 net/core/dev.c:4158 dev_queue_xmit+0x4b/0x60 net/core/dev.c:4164 packet_snd net/packet/af_packet.c:2979 [inline] packet_sendmsg+0x8542/0x9a80 net/packet/af_packet.c:3004 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg net/socket.c:672 [inline] __sys_sendto+0x9f8/0xca0 net/socket.c:1995 __do_sys_sendto net/socket.c:2007 [inline] __se_sys_sendto+0x107/0x130 net/socket.c:2003 __ia32_sys_sendto+0x6e/0x90 net/socket.c:2003 do_syscall_32_irqs_on arch/x86/entry/common.c:430 [inline] __do_fast_syscall_32+0x2af/0x480 arch/x86/entry/common.c:477 do_fast_syscall_32+0x6b/0xd0 arch/x86/entry/common.c:505 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:554 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c RIP: 0023:0xf7f0a549 Code: Bad RIP value. RSP: 002b:00000000f55040cc EFLAGS: 00000296 ORIG_RAX: 0000000000000171 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000020000040 RDX: 000000000001000e RSI: 0000000000000000 RDI: 0000000020000100 RBP: 0000000000000014 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Uninit was stored to memory at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:144 [inline] kmsan_internal_chain_origin+0xad/0x130 mm/kmsan/kmsan.c:310 __msan_chain_origin+0x50/0x90 mm/kmsan/kmsan_instr.c:165 vlan_set_encap_proto include/linux/if_vlan.h:656 [inline] skb_vlan_untag+0x7e7/0xf70 net/core/skbuff.c:5431 __netif_receive_skb_core+0xa4d/0x6520 net/core/dev.c:5119 __netif_receive_skb_one_core net/core/dev.c:5279 [inline] __netif_receive_skb+0x164/0x670 net/core/dev.c:5395 process_backlog+0x50d/0xba0 net/core/dev.c:6239 napi_poll+0x43b/0xfd0 net/core/dev.c:6684 net_rx_action+0x35c/0xd40 net/core/dev.c:6752 __do_softirq+0x2ea/0x7f5 kernel/softirq.c:293 Uninit was created at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:144 [inline] kmsan_internal_poison_shadow+0x66/0xd0 mm/kmsan/kmsan.c:127 kmsan_slab_alloc+0x8a/0xe0 mm/kmsan/kmsan_hooks.c:80 slab_alloc_node mm/slub.c:2839 [inline] __kmalloc_node_track_caller+0xeab/0x12e0 mm/slub.c:4478 __kmalloc_reserve net/core/skbuff.c:142 [inline] __alloc_skb+0x35f/0xb30 net/core/skbuff.c:210 alloc_skb include/linux/skbuff.h:1083 [inline] alloc_skb_with_frags+0x1f2/0xc10 net/core/skbuff.c:5770 sock_alloc_send_pskb+0xc83/0xe50 net/core/sock.c:2356 packet_alloc_skb net/packet/af_packet.c:2827 [inline] packet_snd net/packet/af_packet.c:2922 [inline] packet_sendmsg+0x6abb/0x9a80 net/packet/af_packet.c:3004 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg net/socket.c:672 [inline] __sys_sendto+0x9f8/0xca0 net/socket.c:1995 __do_sys_sendto net/socket.c:2007 [inline] __se_sys_sendto+0x107/0x130 net/socket.c:2003 __ia32_sys_sendto+0x6e/0x90 net/socket.c:2003 do_syscall_32_irqs_on arch/x86/entry/common.c:430 [inline] __do_fast_syscall_32+0x2af/0x480 arch/x86/entry/common.c:477 do_fast_syscall_32+0x6b/0xd0 arch/x86/entry/common.c:505 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:554 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c =====================================================