UBSAN: signed-integer-overflow in ip_idents_reserve ================================================================================ UBSAN: signed-integer-overflow in ./arch/x86/include/asm/atomic.h:165:11 1563201173 + 1189317890 cannot be represented in type 'int' CPU: 1 PID: 222 Comm: kworker/u4:5 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Workqueue: wg-kex-wg0 wg_packet_handshake_send_worker Call Trace: dump_stack+0xfd/0x16e lib/dump_stack.c:118 ubsan_epilogue+0xa/0x30 lib/ubsan.c:148 handle_overflow+0x18e/0x1a0 lib/ubsan.c:180 arch_atomic_add_return arch/x86/include/asm/atomic.h:165 [inline] atomic_add_return include/asm-generic/atomic-instrumented.h:73 [inline] ip_idents_reserve+0x146/0x160 net/ipv4/route.c:521 __ip_select_ident+0xe4/0x1b0 net/ipv4/route.c:538 ip_select_ident_segs include/net/ip.h:525 [inline] ip_select_ident include/net/ip.h:532 [inline] __ip_make_skb+0xf73/0x19b0 net/ipv4/ip_output.c:1551 ip_finish_skb include/net/ip.h:244 [inline] ip_push_pending_frames+0x27/0x80 net/ipv4/ip_output.c:1606 __icmp_send+0xc1b/0xf60 net/ipv4/icmp.c:776 icmp_send include/net/icmp.h:43 [inline] __udp4_lib_rcv+0x14e5/0x2070 net/ipv4/udp.c:2438 ip_protocol_deliver_rcu+0x3ad/0x790 net/ipv4/ip_input.c:204 ip_local_deliver_finish+0x1d5/0x330 net/ipv4/ip_input.c:231 NF_HOOK+0x255/0x2c0 include/linux/netfilter.h:296 NF_HOOK+0x255/0x2c0 include/linux/netfilter.h:296 __netif_receive_skb_one_core net/core/dev.c:5395 [inline] __netif_receive_skb+0xcc/0x290 net/core/dev.c:5509 process_backlog+0x4ef/0x6e0 net/core/dev.c:6416 napi_poll net/core/dev.c:6867 [inline] net_rx_action+0x4ae/0xc20 net/core/dev.c:6937 __do_softirq+0x263/0x914 kernel/softirq.c:298 asm_call_irq_on_stack+0xf/0x20 __run_on_irqstack arch/x86/include/asm/irq_stack.h:26 [inline] run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:77 [inline] do_softirq_own_stack+0x9b/0xe0 arch/x86/kernel/irq_64.c:77 do_softirq+0xc4/0x100 kernel/softirq.c:343 __local_bh_enable_ip+0x11b/0x160 kernel/softirq.c:195 wg_socket_send_skb_to_peer+0x167/0x1c0 drivers/net/wireguard/socket.c:184 wg_packet_send_handshake_initiation drivers/net/wireguard/send.c:40 [inline] wg_packet_handshake_send_worker+0x16b/0x270 drivers/net/wireguard/send.c:51 process_one_work+0x855/0xfd0 kernel/workqueue.c:2282 worker_thread+0xa9b/0x1410 kernel/workqueue.c:2428 kthread+0x320/0x3b0 kernel/kthread.c:328 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 ================================================================================ Warning: Permanently added '10.128.1.246' (ED25519) to the list of known hosts. 2025/09/07 12:29:33 parsed 1 programs [ 74.278128][ T6034] cgroup: Unknown subsys name 'net' [ 74.422193][ T6034] cgroup: Unknown subsys name 'rlimit' [ 75.901128][ T6034] Adding 124996k swap on ./swap-file. Priority:0 extents:1 across:124996k FS [ 76.509912][ T3304] ieee802154 phy0 wpan0: encryption failed: -22 [ 76.516539][ T3304] ieee802154 phy1 wpan1: encryption failed: -22 [ 77.124742][ T6046] IPVS: ftp: loaded support on port[0] = 21 [ 77.390460][ T6050] IPVS: ftp: loaded support on port[0] = 21 [ 77.680498][ T6056] IPVS: ftp: loaded support on port[0] = 21 [ 77.813449][ T6060] IPVS: ftp: loaded support on port[0] = 21 [ 77.949141][ T6063] IPVS: ftp: loaded support on port[0] = 21 [ 78.042083][ T6065] IPVS: ftp: loaded support on port[0] = 21 [ 78.192084][ T6069] IPVS: ftp: loaded support on port[0] = 21 [ 78.322106][ T6073] IPVS: ftp: loaded support on port[0] = 21 [ 78.576839][ T6080] IPVS: ftp: loaded support on port[0] = 21 [ 78.722889][ T6084] IPVS: ftp: loaded support on port[0] = 21 [ 78.939328][ T6088] IPVS: ftp: loaded support on port[0] = 21 [ 79.135433][ T6088] chnl_net:caif_netlink_parms(): no params data found [ 79.192855][ T6088] bridge0: port 1(bridge_slave_0) entered blocking state [ 79.200267][ T6088] bridge0: port 1(bridge_slave_0) entered disabled state [ 79.208681][ T6088] device bridge_slave_0 entered promiscuous mode [ 79.218577][ T6088] bridge0: port 2(bridge_slave_1) entered blocking state [ 79.226291][ T6088] bridge0: port 2(bridge_slave_1) entered disabled state [ 79.234280][ T6088] device bridge_slave_1 entered promiscuous mode [ 79.259729][ T6088] bond0: (slave bond_slave_0): Enslaving as an active interface with an up link [ 79.271098][ T6088] bond0: (slave bond_slave_1): Enslaving as an active interface with an up link [ 79.298601][ T6088] team0: Port device team_slave_0 added [ 79.310370][ T6088] team0: Port device team_slave_1 added [ 79.338126][ T6088] batman_adv: batadv0: Adding interface: batadv_slave_0 [ 79.345245][ T6088] batman_adv: batadv0: The MTU of interface batadv_slave_0 is too small (1500) to handle the transport of batman-adv packets. Packets going over this interface will be fragmented on layer2 which could impact the performance. Setting the MTU to 1560 would solve the problem. [ 79.372111][ T6088] batman_adv: batadv0: Not using interface batadv_slave_0 (retrying later): interface not active [ 79.394334][ T6088] batman_adv: batadv0: Adding interface: batadv_slave_1 [ 79.401881][ T6088] batman_adv: batadv0: The MTU of interface batadv_slave_1 is too small (1500) to handle the transport of batman-adv packets. Packets going over this interface will be fragmented on layer2 which could impact the performance. Setting the MTU to 1560 would solve the problem. [ 79.428997][ T6088] batman_adv: batadv0: Not using interface batadv_slave_1 (retrying later): interface not active [ 79.478773][ T6088] device hsr_slave_0 entered promiscuous mode [ 79.488414][ T6088] device hsr_slave_1 entered promiscuous mode [ 79.575175][ T6088] netdevsim netdevsim0 netdevsim0: renamed from eth0 [ 79.586176][ T6088] netdevsim netdevsim0 netdevsim1: renamed from eth1 [ 79.595223][ T6088] netdevsim netdevsim0 netdevsim2: renamed from eth2 [ 79.604898][ T6088] netdevsim netdevsim0 netdevsim3: renamed from eth3 [ 79.628391][ T6088] bridge0: port 2(bridge_slave_1) entered blocking state [ 79.635600][ T6088] bridge0: port 2(bridge_slave_1) entered forwarding state [ 79.643697][ T6088] bridge0: port 1(bridge_slave_0) entered blocking state [ 79.650833][ T6088] bridge0: port 1(bridge_slave_0) entered forwarding state [ 79.697516][ T6088] 8021q: adding VLAN 0 to HW filter on device bond0 [ 79.711561][ T222] IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready [ 79.722812][ T222] bridge0: port 1(bridge_slave_0) entered disabled state [ 79.731158][ T222] bridge0: port 2(bridge_slave_1) entered disabled state [ 79.746546][ T6088] 8021q: adding VLAN 0 to HW filter on device team0 [ 79.759209][ T222] IPv6: ADDRCONF(NETDEV_CHANGE): bridge_slave_0: link becomes ready [ 79.768312][ T222] bridge0: port 1(bridge_slave_0) entered blocking state [ 79.775395][ T222] bridge0: port 1(bridge_slave_0) entered forwarding state [ 79.790236][ T222] IPv6: ADDRCONF(NETDEV_CHANGE): bridge_slave_1: link becomes ready [ 79.800168][ T222] bridge0: port 2(bridge_slave_1) entered blocking state [ 79.807290][ T222] bridge0: port 2(bridge_slave_1) entered forwarding state [ 79.846771][ T222] IPv6: ADDRCONF(NETDEV_CHANGE): team_slave_0: link becomes ready [ 79.855557][ T222] IPv6: ADDRCONF(NETDEV_CHANGE): team_slave_1: link becomes ready [ 79.866837][ T222] IPv6: ADDRCONF(NETDEV_CHANGE): team0: link becomes ready [ 79.881300][ T28] IPv6: ADDRCONF(NETDEV_CHANGE): hsr_slave_0: link becomes ready [ 79.913789][ T28] IPv6: ADDRCONF(NETDEV_CHANGE): hsr_slave_1: link becomes ready [ 79.924528][ T6088] IPv6: ADDRCONF(NETDEV_CHANGE): hsr0: link becomes ready [ 80.028345][ T28] IPv6: ADDRCONF(NETDEV_CHANGE): vxcan1: link becomes ready [ 80.039083][ T28] IPv6: ADDRCONF(NETDEV_CHANGE): vxcan0: link becomes ready [ 80.055073][ T6088] 8021q: adding VLAN 0 to HW filter on device batadv0 [ 80.085218][ T28] IPv6: ADDRCONF(NETDEV_CHANGE): veth1_virt_wifi: link becomes ready [ 80.094878][ T28] IPv6: ADDRCONF(NETDEV_CHANGE): veth0_virt_wifi: link becomes ready [ 80.118538][ T23] IPv6: ADDRCONF(NETDEV_CHANGE): veth1_vlan: link becomes ready [ 80.127744][ T23] IPv6: ADDRCONF(NETDEV_CHANGE): veth0_vlan: link becomes ready [ 80.158373][ T6088] device veth0_vlan entered promiscuous mode [ 80.165584][ T23] IPv6: ADDRCONF(NETDEV_CHANGE): vlan0: link becomes ready [ 80.174433][ T23] IPv6: ADDRCONF(NETDEV_CHANGE): vlan1: link becomes ready [ 80.187761][ T6088] device veth1_vlan entered promiscuous mode [ 80.231514][ T23] IPv6: ADDRCONF(NETDEV_CHANGE): macvlan0: link becomes ready [ 80.239985][ T23] IPv6: ADDRCONF(NETDEV_CHANGE): macvlan1: link becomes ready [ 80.248267][ T23] IPv6: ADDRCONF(NETDEV_CHANGE): veth1_macvtap: link becomes ready [ 80.256924][ T23] IPv6: ADDRCONF(NETDEV_CHANGE): veth0_macvtap: link becomes ready [ 80.268100][ T6088] device veth0_macvtap entered promiscuous mode [ 80.293349][ T6088] device veth1_macvtap entered promiscuous mode [ 80.309672][ T6088] batman_adv: batadv0: Interface activated: batadv_slave_0 [ 80.319792][ T222] IPv6: ADDRCONF(NETDEV_CHANGE): macvtap0: link becomes ready [ 80.329070][ T222] IPv6: ADDRCONF(NETDEV_CHANGE): macsec0: link becomes ready [ 80.337635][ T222] IPv6: ADDRCONF(NETDEV_CHANGE): batadv_slave_0: link becomes ready [ 80.347072][ T222] IPv6: ADDRCONF(NETDEV_CHANGE): veth0_to_batadv: link becomes ready [ 80.361389][ T6088] batman_adv: batadv0: Interface activated: batadv_slave_1 [ 80.369977][ T222] IPv6: ADDRCONF(NETDEV_CHANGE): batadv_slave_1: link becomes ready [ 80.378863][ T222] IPv6: ADDRCONF(NETDEV_CHANGE): veth1_to_batadv: link becomes ready [ 80.402927][ T6088] netdevsim netdevsim0 netdevsim0: set [1, 0] type 2 family 0 port 6081 - 0 [ 80.412241][ T6088] netdevsim netdevsim0 netdevsim1: set [1, 0] type 2 family 0 port 6081 - 0 [ 80.421550][ T6088] netdevsim netdevsim0 netdevsim2: set [1, 0] type 2 family 0 port 6081 - 0 [ 80.431781][ T6088] netdevsim netdevsim0 netdevsim3: set [1, 0] type 2 family 0 port 6081 - 0 [ 80.457635][ C1] ================================================================================ [ 80.467162][ C1] UBSAN: signed-integer-overflow in ./arch/x86/include/asm/atomic.h:165:11 [ 80.475876][ C1] 1563201173 + 1189317890 cannot be represented in type 'int' [ 80.483483][ C1] CPU: 1 PID: 222 Comm: kworker/u4:5 Not tainted syzkaller #0 [ 80.490952][ C1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 [ 80.501026][ C1] Workqueue: wg-kex-wg0 wg_packet_handshake_send_worker [ 80.507979][ C1] Call Trace: [ 80.511253][ C1] [ 80.514101][ C1] dump_stack+0xfd/0x16e [ 80.518344][ C1] ubsan_epilogue+0xa/0x30 [ 80.522754][ C1] handle_overflow+0x18e/0x1a0 [ 80.527629][ C1] ip_idents_reserve+0x146/0x160 [ 80.532585][ C1] __ip_select_ident+0xe4/0x1b0 [ 80.537445][ C1] __ip_make_skb+0xf73/0x19b0 [ 80.542212][ C1] ip_push_pending_frames+0x27/0x80 [ 80.547408][ C1] __icmp_send+0xc1b/0xf60 [ 80.551853][ C1] __udp4_lib_rcv+0x14e5/0x2070 [ 80.556711][ C1] ip_protocol_deliver_rcu+0x3ad/0x790 [ 80.562188][ C1] ip_local_deliver_finish+0x1d5/0x330 [ 80.567646][ C1] ? NF_HOOK+0x2c0/0x2c0 [ 80.571899][ C1] NF_HOOK+0x255/0x2c0 [ 80.576061][ C1] ? NF_HOOK+0x2c0/0x2c0 [ 80.580314][ C1] ? ip_rcv_core+0xa90/0xa90 [ 80.584912][ C1] NF_HOOK+0x255/0x2c0 [ 80.588977][ C1] ? ip_rcv_core+0xa90/0xa90 [ 80.593575][ C1] ? ip_local_deliver_finish+0x330/0x330 [ 80.599209][ C1] __netif_receive_skb+0xcc/0x290 [ 80.604247][ C1] ? lockdep_hardirqs_on_prepare+0x3d0/0x710 [ 80.610227][ C1] process_backlog+0x4ef/0x6e0 [ 80.615036][ C1] net_rx_action+0x4ae/0xc20 [ 80.619629][ C1] __do_softirq+0x263/0x914 [ 80.624142][ C1] ? asm_call_irq_on_stack+0xf/0x20 [ 80.629347][ C1] asm_call_irq_on_stack+0xf/0x20 [ 80.634537][ C1] [ 80.637471][ C1] do_softirq_own_stack+0x9b/0xe0 [ 80.642484][ C1] do_softirq+0xc4/0x100 [ 80.646727][ C1] ? wg_socket_send_skb_to_peer+0x167/0x1c0 [ 80.652615][ C1] __local_bh_enable_ip+0x11b/0x160 [ 80.657813][ C1] wg_socket_send_skb_to_peer+0x167/0x1c0 [ 80.663617][ C1] wg_packet_handshake_send_worker+0x16b/0x270 [ 80.669777][ C1] process_one_work+0x855/0xfd0 [ 80.674631][ C1] worker_thread+0xa9b/0x1410 [ 80.679329][ C1] kthread+0x320/0x3b0 [ 80.683401][ C1] ? rcu_lock_release+0x20/0x20 [ 80.688265][ C1] ? kthread_blkcg+0xd0/0xd0 [ 80.692942][ C1] ret_from_fork+0x1f/0x30 [ 80.697414][ C1] ================================================================================ [ 80.706757][ C1] Kernel panic - not syncing: UBSAN: panic_on_warn set ... [ 80.714072][ C1] CPU: 1 PID: 222 Comm: kworker/u4:5 Not tainted syzkaller #0 [ 80.721539][ C1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 [ 80.731609][ C1] Workqueue: wg-kex-wg0 wg_packet_handshake_send_worker [ 80.738562][ C1] Call Trace: [ 80.741854][ C1] [ 80.744710][ C1] dump_stack+0xfd/0x16e [ 80.748955][ C1] panic+0x2f0/0x9b0 [ 80.752923][ C1] check_panic_on_warn+0x91/0xd0 [ 80.757869][ C1] handle_overflow+0x18e/0x1a0 [ 80.762669][ C1] ip_idents_reserve+0x146/0x160 [ 80.767755][ C1] __ip_select_ident+0xe4/0x1b0 [ 80.772619][ C1] __ip_make_skb+0xf73/0x19b0 [ 80.777309][ C1] ip_push_pending_frames+0x27/0x80 [ 80.782525][ C1] __icmp_send+0xc1b/0xf60 [ 80.787022][ C1] __udp4_lib_rcv+0x14e5/0x2070 [ 80.791889][ C1] ip_protocol_deliver_rcu+0x3ad/0x790 [ 80.797382][ C1] ip_local_deliver_finish+0x1d5/0x330 [ 80.802847][ C1] ? NF_HOOK+0x2c0/0x2c0 [ 80.807122][ C1] NF_HOOK+0x255/0x2c0 [ 80.811219][ C1] ? NF_HOOK+0x2c0/0x2c0 [ 80.815462][ C1] ? ip_rcv_core+0xa90/0xa90 [ 80.820059][ C1] NF_HOOK+0x255/0x2c0 [ 80.824132][ C1] ? ip_rcv_core+0xa90/0xa90 [ 80.828732][ C1] ? ip_local_deliver_finish+0x330/0x330 [ 80.834551][ C1] __netif_receive_skb+0xcc/0x290 [ 80.839593][ C1] ? lockdep_hardirqs_on_prepare+0x3d0/0x710 [ 80.845666][ C1] process_backlog+0x4ef/0x6e0 [ 80.850439][ C1] net_rx_action+0x4ae/0xc20 [ 80.855032][ C1] __do_softirq+0x263/0x914 [ 80.859539][ C1] ? asm_call_irq_on_stack+0xf/0x20 [ 80.864758][ C1] asm_call_irq_on_stack+0xf/0x20 [ 80.869778][ C1] [ 80.872718][ C1] do_softirq_own_stack+0x9b/0xe0 [ 80.877772][ C1] do_softirq+0xc4/0x100 [ 80.882010][ C1] ? wg_socket_send_skb_to_peer+0x167/0x1c0 [ 80.887895][ C1] __local_bh_enable_ip+0x11b/0x160 [ 80.893110][ C1] wg_socket_send_skb_to_peer+0x167/0x1c0 [ 80.898828][ C1] wg_packet_handshake_send_worker+0x16b/0x270 [ 80.904990][ C1] process_one_work+0x855/0xfd0 [ 80.909850][ C1] worker_thread+0xa9b/0x1410 [ 80.914658][ C1] kthread+0x320/0x3b0 [ 80.919092][ C1] ? rcu_lock_release+0x20/0x20 [ 80.924071][ C1] ? kthread_blkcg+0xd0/0xd0 [ 80.928667][ C1] ret_from_fork+0x1f/0x30 [ 80.933626][ C1] Kernel Offset: disabled [ 80.938079][ C1] Rebooting in 86400 seconds.. syzkaller build log: go env (err=) AR='ar' CC='gcc' CGO_CFLAGS='-O2 -g' CGO_CPPFLAGS='' CGO_CXXFLAGS='-O2 -g' CGO_ENABLED='1' CGO_FFLAGS='-O2 -g' CGO_LDFLAGS='-O2 -g' CXX='g++' GCCGO='gccgo' GO111MODULE='auto' GOAMD64='v1' GOARCH='amd64' GOAUTH='netrc' GOBIN='' GOCACHE='/syzkaller/.cache/go-build' GOCACHEPROG='' GODEBUG='' GOENV='/syzkaller/.config/go/env' GOEXE='' GOEXPERIMENT='' GOFIPS140='off' GOFLAGS='' GOGCCFLAGS='-fPIC -m64 -pthread -Wl,--no-gc-sections -fmessage-length=0 -ffile-prefix-map=/tmp/go-build3326734779=/tmp/go-build -gno-record-gcc-switches' GOHOSTARCH='amd64' GOHOSTOS='linux' GOINSECURE='' GOMOD='/syzkaller/jobs-2/linux/gopath/src/github.com/google/syzkaller/go.mod' GOMODCACHE='/syzkaller/jobs-2/linux/gopath/pkg/mod' GONOPROXY='' GONOSUMDB='' GOOS='linux' GOPATH='/syzkaller/jobs-2/linux/gopath' GOPRIVATE='' GOPROXY='https://proxy.golang.org,direct' GOROOT='/usr/local/go' GOSUMDB='sum.golang.org' GOTELEMETRY='local' GOTELEMETRYDIR='/syzkaller/.config/go/telemetry' GOTMPDIR='' GOTOOLCHAIN='auto' GOTOOLDIR='/usr/local/go/pkg/tool/linux_amd64' GOVCS='' GOVERSION='go1.24.4' GOWORK='' PKG_CONFIG='pkg-config' git status (err=) HEAD detached at ed351ea732 nothing to commit, working tree clean tput: No value for $TERM and no -T specified tput: No value for $TERM and no -T specified Makefile:31: run command via tools/syz-env for best compatibility, see: Makefile:32: https://github.com/google/syzkaller/blob/master/docs/contributing.md#using-syz-env go list -f '{{.Stale}}' ./sys/syz-sysgen | grep -q false || go install ./sys/syz-sysgen make .descriptions tput: No value for $TERM and no -T specified tput: No value for $TERM and no -T specified Makefile:31: run command via tools/syz-env for best compatibility, see: Makefile:32: https://github.com/google/syzkaller/blob/master/docs/contributing.md#using-syz-env bin/syz-sysgen touch .descriptions GOOS=linux GOARCH=amd64 go build -ldflags="-s -w -X github.com/google/syzkaller/prog.GitRevision=ed351ea732d889c7798e7f0226bcaec65a8a6b52 -X github.com/google/syzkaller/prog.gitRevisionDate=20250523-163038" -o ./bin/linux_amd64/syz-execprog github.com/google/syzkaller/tools/syz-execprog mkdir -p ./bin/linux_amd64 g++ -o ./bin/linux_amd64/syz-executor executor/executor.cc \ -m64 -O2 -pthread -Wall -Werror -Wparentheses -Wunused-const-variable -Wframe-larger-than=16384 -Wno-stringop-overflow -Wno-array-bounds -Wno-format-overflow -Wno-unused-but-set-variable -Wno-unused-command-line-argument -static-pie -std=c++17 -I. -Iexecutor/_include -DGOOS_linux=1 -DGOARCH_amd64=1 \ -DHOSTGOOS_linux=1 -DGIT_REVISION=\"ed351ea732d889c7798e7f0226bcaec65a8a6b52\" /usr/bin/ld: /tmp/ccXXMyjz.o: in function `Connection::Connect(char const*, char const*)': executor.cc:(.text._ZN10Connection7ConnectEPKcS1_[_ZN10Connection7ConnectEPKcS1_]+0x104): warning: Using 'gethostbyname' in statically linked applications requires at runtime the shared libraries from the glibc version used for linking