netlink: 28 bytes leftover after parsing attributes in process `syz-executor.1'. ===================================================== BUG: KMSAN: uninit-value in ipt_mangle_out net/ipv4/netfilter/iptable_mangle.c:61 [inline] BUG: KMSAN: uninit-value in iptable_mangle_hook+0x75a/0x8c0 net/ipv4/netfilter/iptable_mangle.c:81 CPU: 0 PID: 9422 Comm: syz-executor.1 Not tainted 5.11.0-rc7-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x21c/0x280 lib/dump_stack.c:120 kmsan_report+0xfb/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+0x75a/0x8c0 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+0x78c/0x840 net/ipv4/ip_output.c:115 ip_local_out+0xa1/0x1e0 net/ipv4/ip_output.c:124 iptunnel_xmit+0x931/0xf20 net/ipv4/ip_tunnel_core.c:82 udp_tunnel_xmit_skb+0x526/0x640 net/ipv4/udp_tunnel_core.c:190 geneve_xmit_skb drivers/net/geneve.c:959 [inline] geneve_xmit+0x209e/0x3c20 drivers/net/geneve.c:1059 __netdev_start_xmit include/linux/netdevice.h:4778 [inline] netdev_start_xmit include/linux/netdevice.h:4792 [inline] xmit_one+0x2b6/0x760 net/core/dev.c:3574 dev_hard_start_xmit+0x196/0x420 net/core/dev.c:3590 sch_direct_xmit+0x57c/0x1a60 net/sched/sch_generic.c:314 qdisc_restart net/sched/sch_generic.c:377 [inline] __qdisc_run+0x35b/0x490 net/sched/sch_generic.c:385 __dev_xmit_skb net/core/dev.c:3813 [inline] __dev_queue_xmit+0x2120/0x45c0 net/core/dev.c:4119 dev_queue_xmit+0x4b/0x60 net/core/dev.c:4184 packet_snd net/packet/af_packet.c:3006 [inline] packet_sendmsg+0x8778/0x9a60 net/packet/af_packet.c:3031 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg net/socket.c:672 [inline] __sys_sendto+0x9ea/0xc60 net/socket.c:1975 __do_sys_sendto net/socket.c:1987 [inline] __se_sys_sendto+0x107/0x130 net/socket.c:1983 __ia32_sys_sendto+0x6e/0x90 net/socket.c:1983 do_syscall_32_irqs_on arch/x86/entry/common.c:79 [inline] __do_fast_syscall_32+0x102/0x160 arch/x86/entry/common.c:141 do_fast_syscall_32+0x6a/0xc0 arch/x86/entry/common.c:166 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:209 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c RIP: 0023:0xf7f2e549 Code: 03 74 c0 01 10 05 03 74 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 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00 RSP: 002b:00000000f55285fc 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+0xbd6/0xf20 net/ipv4/ip_tunnel_core.c:76 udp_tunnel_xmit_skb+0x526/0x640 net/ipv4/udp_tunnel_core.c:190 geneve_xmit_skb drivers/net/geneve.c:959 [inline] geneve_xmit+0x209e/0x3c20 drivers/net/geneve.c:1059 __netdev_start_xmit include/linux/netdevice.h:4778 [inline] netdev_start_xmit include/linux/netdevice.h:4792 [inline] xmit_one+0x2b6/0x760 net/core/dev.c:3574 dev_hard_start_xmit+0x196/0x420 net/core/dev.c:3590 sch_direct_xmit+0x57c/0x1a60 net/sched/sch_generic.c:314 qdisc_restart net/sched/sch_generic.c:377 [inline] __qdisc_run+0x35b/0x490 net/sched/sch_generic.c:385 __dev_xmit_skb net/core/dev.c:3813 [inline] __dev_queue_xmit+0x2120/0x45c0 net/core/dev.c:4119 dev_queue_xmit+0x4b/0x60 net/core/dev.c:4184 packet_snd net/packet/af_packet.c:3006 [inline] packet_sendmsg+0x8778/0x9a60 net/packet/af_packet.c:3031 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg net/socket.c:672 [inline] __sys_sendto+0x9ea/0xc60 net/socket.c:1975 __do_sys_sendto net/socket.c:1987 [inline] __se_sys_sendto+0x107/0x130 net/socket.c:1983 __ia32_sys_sendto+0x6e/0x90 net/socket.c:1983 do_syscall_32_irqs_on arch/x86/entry/common.c:79 [inline] __do_fast_syscall_32+0x102/0x160 arch/x86/entry/common.c:141 do_fast_syscall_32+0x6a/0xc0 arch/x86/entry/common.c:166 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:209 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:2907 [inline] __kmalloc_node_track_caller+0xa37/0x1430 mm/slub.c:4527 __kmalloc_reserve net/core/skbuff.c:142 [inline] __alloc_skb+0x2f8/0xb30 net/core/skbuff.c:210 alloc_skb include/linux/skbuff.h:1099 [inline] alloc_skb_with_frags+0x1f3/0xc10 net/core/skbuff.c:5894 sock_alloc_send_pskb+0xdc1/0xf90 net/core/sock.c:2348 packet_alloc_skb net/packet/af_packet.c:2854 [inline] packet_snd net/packet/af_packet.c:2949 [inline] packet_sendmsg+0x6aab/0x9a60 net/packet/af_packet.c:3031 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg net/socket.c:672 [inline] __sys_sendto+0x9ea/0xc60 net/socket.c:1975 __do_sys_sendto net/socket.c:1987 [inline] __se_sys_sendto+0x107/0x130 net/socket.c:1983 __ia32_sys_sendto+0x6e/0x90 net/socket.c:1983 do_syscall_32_irqs_on arch/x86/entry/common.c:79 [inline] __do_fast_syscall_32+0x102/0x160 arch/x86/entry/common.c:141 do_fast_syscall_32+0x6a/0xc0 arch/x86/entry/common.c:166 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:209 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c =====================================================