netlink: 12 bytes leftover after parsing attributes in process `syz-executor.3'. ===================================================== BUG: KMSAN: uninit-value in ipt_mangle_out syzkaller/managers/upstream-kmsan-gce/kernel/net/ipv4/netfilter/iptable_mangle.c:61 [inline] BUG: KMSAN: uninit-value in iptable_mangle_hook+0x75a/0x8c0 syzkaller/managers/upstream-kmsan-gce/kernel/net/ipv4/netfilter/iptable_mangle.c:81 CPU: 1 PID: 10937 Comm: syz-executor.3 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 syzkaller/managers/upstream-kmsan-gce/kernel/lib/dump_stack.c:77 [inline] dump_stack+0x21c/0x280 syzkaller/managers/upstream-kmsan-gce/kernel/lib/dump_stack.c:118 kmsan_report+0xfb/0x1e0 syzkaller/managers/upstream-kmsan-gce/kernel/mm/kmsan/kmsan_report.c:118 __msan_warning+0x5f/0xa0 syzkaller/managers/upstream-kmsan-gce/kernel/mm/kmsan/kmsan_instr.c:197 ipt_mangle_out syzkaller/managers/upstream-kmsan-gce/kernel/net/ipv4/netfilter/iptable_mangle.c:61 [inline] iptable_mangle_hook+0x75a/0x8c0 syzkaller/managers/upstream-kmsan-gce/kernel/net/ipv4/netfilter/iptable_mangle.c:81 nf_hook_entry_hookfn syzkaller/managers/upstream-kmsan-gce/kernel/./include/linux/netfilter.h:136 [inline] nf_hook_slow+0x17b/0x460 syzkaller/managers/upstream-kmsan-gce/kernel/net/netfilter/core.c:589 nf_hook syzkaller/managers/upstream-kmsan-gce/kernel/./include/linux/netfilter.h:256 [inline] __ip_local_out+0x78c/0x840 syzkaller/managers/upstream-kmsan-gce/kernel/net/ipv4/ip_output.c:115 ip_local_out+0xa1/0x1e0 syzkaller/managers/upstream-kmsan-gce/kernel/net/ipv4/ip_output.c:124 iptunnel_xmit+0x931/0xf20 syzkaller/managers/upstream-kmsan-gce/kernel/net/ipv4/ip_tunnel_core.c:82 udp_tunnel_xmit_skb+0x526/0x640 syzkaller/managers/upstream-kmsan-gce/kernel/net/ipv4/udp_tunnel_core.c:190 geneve_xmit_skb syzkaller/managers/upstream-kmsan-gce/kernel/drivers/net/geneve.c:959 [inline] geneve_xmit+0x209e/0x3c20 syzkaller/managers/upstream-kmsan-gce/kernel/drivers/net/geneve.c:1059 __netdev_start_xmit syzkaller/managers/upstream-kmsan-gce/kernel/./include/linux/netdevice.h:4718 [inline] netdev_start_xmit syzkaller/managers/upstream-kmsan-gce/kernel/./include/linux/netdevice.h:4732 [inline] xmit_one+0x2b6/0x760 syzkaller/managers/upstream-kmsan-gce/kernel/net/core/dev.c:3564 dev_hard_start_xmit syzkaller/managers/upstream-kmsan-gce/kernel/net/core/dev.c:3580 [inline] __dev_queue_xmit+0x3426/0x4590 syzkaller/managers/upstream-kmsan-gce/kernel/net/core/dev.c:4140 dev_queue_xmit+0x4b/0x60 syzkaller/managers/upstream-kmsan-gce/kernel/net/core/dev.c:4173 packet_snd syzkaller/managers/upstream-kmsan-gce/kernel/net/packet/af_packet.c:2992 [inline] packet_sendmsg+0x8778/0x9a60 syzkaller/managers/upstream-kmsan-gce/kernel/net/packet/af_packet.c:3017 sock_sendmsg_nosec syzkaller/managers/upstream-kmsan-gce/kernel/net/socket.c:651 [inline] sock_sendmsg syzkaller/managers/upstream-kmsan-gce/kernel/net/socket.c:671 [inline] __sys_sendto+0x9dc/0xc80 syzkaller/managers/upstream-kmsan-gce/kernel/net/socket.c:1992 __do_sys_sendto syzkaller/managers/upstream-kmsan-gce/kernel/net/socket.c:2004 [inline] __se_sys_sendto+0x107/0x130 syzkaller/managers/upstream-kmsan-gce/kernel/net/socket.c:2000 __x64_sys_sendto+0x6e/0x90 syzkaller/managers/upstream-kmsan-gce/kernel/net/socket.c:2000 do_syscall_64+0x9f/0x140 syzkaller/managers/upstream-kmsan-gce/kernel/arch/x86/entry/common.c:48 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x465b09 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f5c216b6188 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000465b09 RDX: 000000000000000e RSI: 0000000020000080 RDI: 0000000000000003 RBP: 00000000004b069f R08: 00000000200002c0 R09: 0000000000000014 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60 R13: 0000000000a9fb1f R14: 00007f5c216b6300 R15: 0000000000022000 Uninit was stored to memory at: kmsan_save_stack_with_flags syzkaller/managers/upstream-kmsan-gce/kernel/mm/kmsan/kmsan.c:121 [inline] kmsan_internal_chain_origin+0xad/0x130 syzkaller/managers/upstream-kmsan-gce/kernel/mm/kmsan/kmsan.c:289 __msan_chain_origin+0x57/0xa0 syzkaller/managers/upstream-kmsan-gce/kernel/mm/kmsan/kmsan_instr.c:147 iptunnel_xmit+0xbd6/0xf20 syzkaller/managers/upstream-kmsan-gce/kernel/net/ipv4/ip_tunnel_core.c:76 udp_tunnel_xmit_skb+0x526/0x640 syzkaller/managers/upstream-kmsan-gce/kernel/net/ipv4/udp_tunnel_core.c:190 geneve_xmit_skb syzkaller/managers/upstream-kmsan-gce/kernel/drivers/net/geneve.c:959 [inline] geneve_xmit+0x209e/0x3c20 syzkaller/managers/upstream-kmsan-gce/kernel/drivers/net/geneve.c:1059 __netdev_start_xmit syzkaller/managers/upstream-kmsan-gce/kernel/./include/linux/netdevice.h:4718 [inline] netdev_start_xmit syzkaller/managers/upstream-kmsan-gce/kernel/./include/linux/netdevice.h:4732 [inline] xmit_one+0x2b6/0x760 syzkaller/managers/upstream-kmsan-gce/kernel/net/core/dev.c:3564 dev_hard_start_xmit syzkaller/managers/upstream-kmsan-gce/kernel/net/core/dev.c:3580 [inline] __dev_queue_xmit+0x3426/0x4590 syzkaller/managers/upstream-kmsan-gce/kernel/net/core/dev.c:4140 dev_queue_xmit+0x4b/0x60 syzkaller/managers/upstream-kmsan-gce/kernel/net/core/dev.c:4173 packet_snd syzkaller/managers/upstream-kmsan-gce/kernel/net/packet/af_packet.c:2992 [inline] packet_sendmsg+0x8778/0x9a60 syzkaller/managers/upstream-kmsan-gce/kernel/net/packet/af_packet.c:3017 sock_sendmsg_nosec syzkaller/managers/upstream-kmsan-gce/kernel/net/socket.c:651 [inline] sock_sendmsg syzkaller/managers/upstream-kmsan-gce/kernel/net/socket.c:671 [inline] __sys_sendto+0x9dc/0xc80 syzkaller/managers/upstream-kmsan-gce/kernel/net/socket.c:1992 __do_sys_sendto syzkaller/managers/upstream-kmsan-gce/kernel/net/socket.c:2004 [inline] __se_sys_sendto+0x107/0x130 syzkaller/managers/upstream-kmsan-gce/kernel/net/socket.c:2000 __x64_sys_sendto+0x6e/0x90 syzkaller/managers/upstream-kmsan-gce/kernel/net/socket.c:2000 do_syscall_64+0x9f/0x140 syzkaller/managers/upstream-kmsan-gce/kernel/arch/x86/entry/common.c:48 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Uninit was created at: kmsan_save_stack_with_flags syzkaller/managers/upstream-kmsan-gce/kernel/mm/kmsan/kmsan.c:121 [inline] kmsan_internal_poison_shadow+0x5c/0xf0 syzkaller/managers/upstream-kmsan-gce/kernel/mm/kmsan/kmsan.c:104 kmsan_slab_alloc+0x8d/0xe0 syzkaller/managers/upstream-kmsan-gce/kernel/mm/kmsan/kmsan_hooks.c:76 slab_alloc_node syzkaller/managers/upstream-kmsan-gce/kernel/mm/slub.c:2906 [inline] __kmalloc_node_track_caller+0xa48/0x1610 syzkaller/managers/upstream-kmsan-gce/kernel/mm/slub.c:4512 __kmalloc_reserve syzkaller/managers/upstream-kmsan-gce/kernel/net/core/skbuff.c:142 [inline] __alloc_skb+0x318/0xb00 syzkaller/managers/upstream-kmsan-gce/kernel/net/core/skbuff.c:210 alloc_skb syzkaller/managers/upstream-kmsan-gce/kernel/./include/linux/skbuff.h:1094 [inline] alloc_skb_with_frags+0x1f3/0xc10 syzkaller/managers/upstream-kmsan-gce/kernel/net/core/skbuff.c:5832 sock_alloc_send_pskb+0xcc4/0xe80 syzkaller/managers/upstream-kmsan-gce/kernel/net/core/sock.c:2329 packet_alloc_skb syzkaller/managers/upstream-kmsan-gce/kernel/net/packet/af_packet.c:2840 [inline] packet_snd syzkaller/managers/upstream-kmsan-gce/kernel/net/packet/af_packet.c:2935 [inline] packet_sendmsg+0x6aab/0x9a60 syzkaller/managers/upstream-kmsan-gce/kernel/net/packet/af_packet.c:3017 sock_sendmsg_nosec syzkaller/managers/upstream-kmsan-gce/kernel/net/socket.c:651 [inline] sock_sendmsg syzkaller/managers/upstream-kmsan-gce/kernel/net/socket.c:671 [inline] __sys_sendto+0x9dc/0xc80 syzkaller/managers/upstream-kmsan-gce/kernel/net/socket.c:1992 __do_sys_sendto syzkaller/managers/upstream-kmsan-gce/kernel/net/socket.c:2004 [inline] __se_sys_sendto+0x107/0x130 syzkaller/managers/upstream-kmsan-gce/kernel/net/socket.c:2000 __x64_sys_sendto+0x6e/0x90 syzkaller/managers/upstream-kmsan-gce/kernel/net/socket.c:2000 do_syscall_64+0x9f/0x140 syzkaller/managers/upstream-kmsan-gce/kernel/arch/x86/entry/common.c:48 entry_SYSCALL_64_after_hwframe+0x44/0xa9 =====================================================