================================================================== BUG: KMSAN: uninit-value in br_nf_forward_arp+0x88a/0xea0 net/bridge/br_netfilter_hooks.c:633 CPU: 0 PID: 11909 Comm: syz-executor995 Not tainted 5.2.0+ #15 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+0x191/0x1f0 lib/dump_stack.c:113 kmsan_report+0x162/0x2d0 mm/kmsan/kmsan_report.c:109 __msan_warning+0x75/0xe0 mm/kmsan/kmsan_instr.c:294 br_nf_forward_arp+0x88a/0xea0 net/bridge/br_netfilter_hooks.c:633 nf_hook_entry_hookfn include/linux/netfilter.h:135 [inline] nf_hook_slow+0x18b/0x410 net/netfilter/core.c:512 nf_hook include/linux/netfilter.h:260 [inline] NF_HOOK include/linux/netfilter.h:303 [inline] __br_forward+0x78f/0xe30 net/bridge/br_forward.c:109 br_flood+0xef0/0xfe0 net/bridge/br_forward.c:234 br_handle_frame_finish+0x1a02/0x1bd0 net/bridge/br_input.c:164 nf_hook_bridge_pre net/bridge/br_input.c:247 [inline] br_handle_frame+0xfc3/0x1ec0 net/bridge/br_input.c:350 __netif_receive_skb_core+0x20a9/0x5360 net/core/dev.c:4910 __netif_receive_skb_one_core net/core/dev.c:5007 [inline] __netif_receive_skb net/core/dev.c:5123 [inline] process_backlog+0x612/0x1410 net/core/dev.c:5934 napi_poll net/core/dev.c:6357 [inline] net_rx_action+0x738/0x1940 net/core/dev.c:6423 __do_softirq+0x4ad/0x858 kernel/softirq.c:293 do_softirq_own_stack+0x49/0x80 arch/x86/entry/entry_64.S:1052 do_softirq kernel/softirq.c:338 [inline] __local_bh_enable_ip+0x199/0x1e0 kernel/softirq.c:190 local_bh_enable+0x36/0x40 include/linux/bottom_half.h:32 rcu_read_unlock_bh include/linux/rcupdate.h:682 [inline] __dev_queue_xmit+0x304d/0x4270 net/core/dev.c:3904 dev_queue_xmit+0x4b/0x60 net/core/dev.c:3910 packet_snd net/packet/af_packet.c:2941 [inline] packet_sendmsg+0x83f7/0x9290 net/packet/af_packet.c:2966 sock_sendmsg_nosec net/socket.c:646 [inline] sock_sendmsg net/socket.c:665 [inline] ___sys_sendmsg+0x12ff/0x13c0 net/socket.c:2286 __sys_sendmmsg+0x53a/0xae0 net/socket.c:2381 __do_sys_sendmmsg net/socket.c:2410 [inline] __se_sys_sendmmsg+0xbd/0xe0 net/socket.c:2407 __x64_sys_sendmmsg+0x56/0x70 net/socket.c:2407 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:302 entry_SYSCALL_64_after_hwframe+0x63/0xe7 RIP: 0033:0x441ae9 Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 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 7b 10 fc ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffc24098708 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000441ae9 RDX: 0000000000000001 RSI: 0000000020004e80 RDI: 0000000000000004 RBP: 00007ffc24098720 R08: 0000000001bbbbbb R09: 0000000001bbbbbb R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000403080 R14: 0000000000000000 R15: 0000000000000000 Uninit was created at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:187 [inline] kmsan_internal_poison_shadow+0x53/0xa0 mm/kmsan/kmsan.c:146 kmsan_slab_alloc+0xaa/0x120 mm/kmsan/kmsan_hooks.c:175 slab_alloc_node mm/slub.c:2771 [inline] __kmalloc_node_track_caller+0xc8f/0xf10 mm/slub.c:4389 __kmalloc_reserve net/core/skbuff.c:138 [inline] __alloc_skb+0x306/0xa10 net/core/skbuff.c:206 alloc_skb include/linux/skbuff.h:1055 [inline] alloc_skb_with_frags+0x18c/0xa80 net/core/skbuff.c:5328 sock_alloc_send_pskb+0xafd/0x10a0 net/core/sock.c:2219 packet_alloc_skb net/packet/af_packet.c:2789 [inline] packet_snd net/packet/af_packet.c:2884 [inline] packet_sendmsg+0x6627/0x9290 net/packet/af_packet.c:2966 sock_sendmsg_nosec net/socket.c:646 [inline] sock_sendmsg net/socket.c:665 [inline] ___sys_sendmsg+0x12ff/0x13c0 net/socket.c:2286 __sys_sendmmsg+0x53a/0xae0 net/socket.c:2381 __do_sys_sendmmsg net/socket.c:2410 [inline] __se_sys_sendmmsg+0xbd/0xe0 net/socket.c:2407 __x64_sys_sendmmsg+0x56/0x70 net/socket.c:2407 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:302 entry_SYSCALL_64_after_hwframe+0x63/0xe7 ==================================================================