===================================================== BUG: KMSAN: uninit-value in ipt_mangle_out net/ipv4/netfilter/iptable_mangle.c:61 [inline] BUG: KMSAN: uninit-value in iptable_mangle_hook+0x8a0/0x8e0 net/ipv4/netfilter/iptable_mangle.c:81 CPU: 1 PID: 9058 Comm: syz-executor.0 Not tainted 5.10.0-rc4-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:118 __msan_warning+0x5f/0xa0 mm/kmsan/kmsan_instr.c:197 ipt_mangle_out net/ipv4/netfilter/iptable_mangle.c:61 [inline] iptable_mangle_hook+0x8a0/0x8e0 net/ipv4/netfilter/iptable_mangle.c:81 nf_hook_entry_hookfn include/linux/netfilter.h:136 [inline] nf_hook_slow+0x17b/0x460 net/netfilter/core.c:589 nf_hook include/linux/netfilter.h:256 [inline] __ip_local_out+0x7a6/0x860 net/ipv4/ip_output.c:115 ip_local_out+0xa1/0x1e0 net/ipv4/ip_output.c:124 iptunnel_xmit+0x932/0xf20 net/ipv4/ip_tunnel_core.c:82 udp_tunnel_xmit_skb+0x52a/0x650 net/ipv4/udp_tunnel_core.c:190 geneve_xmit_skb drivers/net/geneve.c:959 [inline] geneve_xmit+0x3908/0x3cc0 drivers/net/geneve.c:1059 __netdev_start_xmit include/linux/netdevice.h:4718 [inline] netdev_start_xmit include/linux/netdevice.h:4732 [inline] xmit_one+0x2b9/0x770 net/core/dev.c:3564 dev_hard_start_xmit+0x195/0x430 net/core/dev.c:3580 sch_direct_xmit+0x5c7/0x1a30 net/sched/sch_generic.c:314 qdisc_restart net/sched/sch_generic.c:377 [inline] __qdisc_run+0x361/0x4a0 net/sched/sch_generic.c:385 __dev_xmit_skb net/core/dev.c:3803 [inline] __dev_queue_xmit+0x1de2/0x4520 net/core/dev.c:4108 dev_queue_xmit+0x4b/0x60 net/core/dev.c:4173 packet_snd net/packet/af_packet.c:2992 [inline] packet_sendmsg+0x86f9/0x99d0 net/packet/af_packet.c:3017 sock_sendmsg_nosec net/socket.c:651 [inline] sock_sendmsg net/socket.c:671 [inline] __sys_sendto+0x9dc/0xc80 net/socket.c:1992 __do_sys_sendto net/socket.c:2004 [inline] __se_sys_sendto+0x107/0x130 net/socket.c:2000 __ia32_sys_sendto+0x6e/0x90 net/socket.c:2000 do_syscall_32_irqs_on arch/x86/entry/common.c:80 [inline] __do_fast_syscall_32+0x102/0x160 arch/x86/entry/common.c:139 do_fast_syscall_32+0x6a/0xc0 arch/x86/entry/common.c:162 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:205 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c RIP: 0023:0xf7f47549 Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 eb 0d 90 90 90 90 90 90 90 90 90 90 90 90 RSP: 002b:00000000f54ff0cc EFLAGS: 00000296 ORIG_RAX: 0000000000000171 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000020000080 RDX: 000000000000000e RSI: 0000000000000000 RDI: 00000000200002c0 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:121 [inline] kmsan_internal_chain_origin+0xad/0x130 mm/kmsan/kmsan.c:289 __msan_chain_origin+0x57/0xa0 mm/kmsan/kmsan_instr.c:147 iptunnel_xmit+0xbd9/0xf20 net/ipv4/ip_tunnel_core.c:76 udp_tunnel_xmit_skb+0x52a/0x650 net/ipv4/udp_tunnel_core.c:190 geneve_xmit_skb drivers/net/geneve.c:959 [inline] geneve_xmit+0x3908/0x3cc0 drivers/net/geneve.c:1059 __netdev_start_xmit include/linux/netdevice.h:4718 [inline] netdev_start_xmit include/linux/netdevice.h:4732 [inline] xmit_one+0x2b9/0x770 net/core/dev.c:3564 dev_hard_start_xmit+0x195/0x430 net/core/dev.c:3580 sch_direct_xmit+0x5c7/0x1a30 net/sched/sch_generic.c:314 qdisc_restart net/sched/sch_generic.c:377 [inline] __qdisc_run+0x361/0x4a0 net/sched/sch_generic.c:385 __dev_xmit_skb net/core/dev.c:3803 [inline] __dev_queue_xmit+0x1de2/0x4520 net/core/dev.c:4108 dev_queue_xmit+0x4b/0x60 net/core/dev.c:4173 packet_snd net/packet/af_packet.c:2992 [inline] packet_sendmsg+0x86f9/0x99d0 net/packet/af_packet.c:3017 sock_sendmsg_nosec net/socket.c:651 [inline] sock_sendmsg net/socket.c:671 [inline] __sys_sendto+0x9dc/0xc80 net/socket.c:1992 __do_sys_sendto net/socket.c:2004 [inline] __se_sys_sendto+0x107/0x130 net/socket.c:2000 __ia32_sys_sendto+0x6e/0x90 net/socket.c:2000 do_syscall_32_irqs_on arch/x86/entry/common.c:80 [inline] __do_fast_syscall_32+0x102/0x160 arch/x86/entry/common.c:139 do_fast_syscall_32+0x6a/0xc0 arch/x86/entry/common.c:162 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:205 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c Uninit was created at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:121 [inline] kmsan_internal_poison_shadow+0x5c/0xf0 mm/kmsan/kmsan.c:104 kmsan_slab_alloc+0x8d/0xe0 mm/kmsan/kmsan_hooks.c:76 slab_alloc_node mm/slub.c:2906 [inline] __kmalloc_node_track_caller+0xc61/0x15f0 mm/slub.c:4512 __kmalloc_reserve net/core/skbuff.c:142 [inline] __alloc_skb+0x309/0xae0 net/core/skbuff.c:210 alloc_skb include/linux/skbuff.h:1094 [inline] alloc_skb_with_frags+0x1f3/0xc20 net/core/skbuff.c:5832 sock_alloc_send_pskb+0xc73/0xe40 net/core/sock.c:2329 packet_alloc_skb net/packet/af_packet.c:2840 [inline] packet_snd net/packet/af_packet.c:2935 [inline] packet_sendmsg+0x6aa3/0x99d0 net/packet/af_packet.c:3017 sock_sendmsg_nosec net/socket.c:651 [inline] sock_sendmsg net/socket.c:671 [inline] __sys_sendto+0x9dc/0xc80 net/socket.c:1992 __do_sys_sendto net/socket.c:2004 [inline] __se_sys_sendto+0x107/0x130 net/socket.c:2000 __ia32_sys_sendto+0x6e/0x90 net/socket.c:2000 do_syscall_32_irqs_on arch/x86/entry/common.c:80 [inline] __do_fast_syscall_32+0x102/0x160 arch/x86/entry/common.c:139 do_fast_syscall_32+0x6a/0xc0 arch/x86/entry/common.c:162 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:205 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c =====================================================