================================================================== BUG: KMSAN: uninit-value in gue_err+0x482/0xb00 net/ipv4/fou.c:1031 CPU: 0 PID: 24018 Comm: syz-executor.2 Not tainted 5.0.0-rc1+ #9 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+0x173/0x1d0 lib/dump_stack.c:113 kmsan_report+0x12e/0x2a0 mm/kmsan/kmsan.c:600 __msan_warning+0x82/0xf0 mm/kmsan/kmsan_instr.c:313 gue_err+0x482/0xb00 net/ipv4/fou.c:1031 __udp4_lib_err_encap_no_sk net/ipv4/udp.c:569 [inline] __udp4_lib_err_encap net/ipv4/udp.c:624 [inline] __udp4_lib_err+0x12e6/0x1d40 net/ipv4/udp.c:663 udp_err+0x74/0x90 net/ipv4/udp.c:735 icmp_socket_deliver net/ipv4/icmp.c:766 [inline] icmp_unreach+0xb65/0x1070 net/ipv4/icmp.c:883 icmp_rcv+0x11a1/0x1950 net/ipv4/icmp.c:1065 ip_protocol_deliver_rcu+0x584/0xba0 net/ipv4/ip_input.c:208 ip_local_deliver_finish net/ipv4/ip_input.c:234 [inline] NF_HOOK include/linux/netfilter.h:289 [inline] ip_local_deliver+0x624/0x7b0 net/ipv4/ip_input.c:255 dst_input include/net/dst.h:450 [inline] ip_rcv_finish net/ipv4/ip_input.c:414 [inline] NF_HOOK include/linux/netfilter.h:289 [inline] ip_rcv+0x6b6/0x740 net/ipv4/ip_input.c:523 __netif_receive_skb_one_core net/core/dev.c:4973 [inline] __netif_receive_skb net/core/dev.c:5083 [inline] process_backlog+0x756/0x10e0 net/core/dev.c:5923 napi_poll net/core/dev.c:6346 [inline] net_rx_action+0x78b/0x1a60 net/core/dev.c:6412 __do_softirq+0x53f/0x93a kernel/softirq.c:293 do_softirq_own_stack+0x49/0x80 arch/x86/entry/entry_64.S:1039 do_softirq kernel/softirq.c:338 [inline] __local_bh_enable_ip+0x16f/0x1a0 kernel/softirq.c:190 local_bh_enable+0x36/0x40 include/linux/bottom_half.h:32 rcu_read_unlock_bh include/linux/rcupdate.h:696 [inline] ip_finish_output2+0x1627/0x1820 net/ipv4/ip_output.c:231 ip_finish_output+0xd2b/0xfd0 net/ipv4/ip_output.c:317 NF_HOOK_COND include/linux/netfilter.h:278 [inline] ip_output+0x53f/0x610 net/ipv4/ip_output.c:405 dst_output include/net/dst.h:444 [inline] ip_local_out net/ipv4/ip_output.c:124 [inline] ip_send_skb+0x179/0x360 net/ipv4/ip_output.c:1465 udp_send_skb+0x13ff/0x18b0 net/ipv4/udp.c:891 udp_sendmsg+0x3aa4/0x40f0 net/ipv4/udp.c:1178 udpv6_sendmsg+0x1403/0x45d0 net/ipv6/udp.c:1279 inet_sendmsg+0x54a/0x720 net/ipv4/af_inet.c:798 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg net/socket.c:631 [inline] ___sys_sendmsg+0xdb9/0x11b0 net/socket.c:2116 __sys_sendmmsg+0x580/0xad0 net/socket.c:2211 __do_sys_sendmmsg net/socket.c:2240 [inline] __se_sys_sendmmsg+0xbd/0xe0 net/socket.c:2237 __x64_sys_sendmmsg+0x56/0x70 net/socket.c:2237 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291 entry_SYSCALL_64_after_hwframe+0x63/0xe7 RIP: 0033:0x457e29 Code: ad b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fc72bd6fc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000457e29 RDX: 040000000000003e RSI: 0000000020000240 RDI: 0000000000000003 RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fc72bd706d4 R13: 00000000004c4dd7 R14: 00000000004d8b10 R15: 00000000ffffffff Uninit was created at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:205 [inline] kmsan_internal_poison_shadow+0x92/0x150 mm/kmsan/kmsan.c:159 kmsan_kmalloc+0xa6/0x130 mm/kmsan/kmsan_hooks.c:176 kmsan_slab_alloc+0xe/0x10 mm/kmsan/kmsan_hooks.c:185 slab_post_alloc_hook mm/slab.h:446 [inline] slab_alloc_node mm/slub.c:2754 [inline] __kmalloc_node_track_caller+0xe9e/0xff0 mm/slub.c:4377 __kmalloc_reserve net/core/skbuff.c:140 [inline] __alloc_skb+0x309/0xa20 net/core/skbuff.c:208 alloc_skb include/linux/skbuff.h:1012 [inline] alloc_skb_with_frags+0x1c7/0xac0 net/core/skbuff.c:5288 sock_alloc_send_pskb+0xafd/0x10a0 net/core/sock.c:2091 sock_alloc_send_skb+0xca/0xe0 net/core/sock.c:2108 __ip_append_data+0x34cd/0x5000 net/ipv4/ip_output.c:998 ip_append_data+0x324/0x480 net/ipv4/ip_output.c:1220 icmp_push_reply+0x23d/0x7e0 net/ipv4/icmp.c:375 icmp_send+0x2e74/0x30c0 net/ipv4/icmp.c:736 __udp4_lib_rcv+0x36c9/0x4b70 net/ipv4/udp.c:2313 udp_rcv+0x5c/0x70 net/ipv4/udp.c:2472 ip_protocol_deliver_rcu+0x584/0xba0 net/ipv4/ip_input.c:208 ip_local_deliver_finish net/ipv4/ip_input.c:234 [inline] NF_HOOK include/linux/netfilter.h:289 [inline] ip_local_deliver+0x624/0x7b0 net/ipv4/ip_input.c:255 dst_input include/net/dst.h:450 [inline] ip_rcv_finish net/ipv4/ip_input.c:414 [inline] NF_HOOK include/linux/netfilter.h:289 [inline] ip_rcv+0x6b6/0x740 net/ipv4/ip_input.c:523 __netif_receive_skb_one_core net/core/dev.c:4973 [inline] __netif_receive_skb net/core/dev.c:5083 [inline] process_backlog+0x756/0x10e0 net/core/dev.c:5923 napi_poll net/core/dev.c:6346 [inline] net_rx_action+0x78b/0x1a60 net/core/dev.c:6412 __do_softirq+0x53f/0x93a kernel/softirq.c:293 ==================================================================