UBSAN: signed-integer-overflow in ip_idents_reserve ================================================================================ UBSAN: signed-integer-overflow in ./arch/x86/include/asm/atomic.h:165:11 -1399202697 + -1961381633 cannot be represented in type 'int' CPU: 1 PID: 27 Comm: kworker/u4:2 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 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+0x192/0x1b0 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+0x14a/0x170 net/ipv4/route.c:521 __ip_select_ident+0xe4/0x1c0 net/ipv4/route.c:538 iptunnel_xmit+0x468/0x850 net/ipv4/ip_tunnel_core.c:80 udp_tunnel_xmit_skb+0x1ba/0x290 net/ipv4/udp_tunnel_core.c:190 send4+0x5d4/0xaf0 drivers/net/wireguard/socket.c:85 wg_socket_send_skb_to_peer+0xcd/0x1c0 drivers/net/wireguard/socket.c:175 wg_packet_send_handshake_initiation drivers/net/wireguard/send.c:40 [inline] wg_packet_handshake_send_worker+0x16b/0x280 drivers/net/wireguard/send.c:51 process_one_work+0x85e/0xff0 kernel/workqueue.c:2282 worker_thread+0xa9b/0x1430 kernel/workqueue.c:2428 kthread+0x386/0x410 kernel/kthread.c:328 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 ================================================================================ Kernel panic - not syncing: UBSAN: panic_on_warn set ... CPU: 1 PID: 27 Comm: kworker/u4:2 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Workqueue: wg-kex-wg0 wg_packet_handshake_send_worker Call Trace: dump_stack+0xfd/0x16e lib/dump_stack.c:118 panic+0x2f0/0x9c0 kernel/panic.c:308 check_panic_on_warn+0x95/0xe0 kernel/panic.c:228 handle_overflow+0x192/0x1b0 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+0x14a/0x170 net/ipv4/route.c:521 __ip_select_ident+0xe4/0x1c0 net/ipv4/route.c:538 iptunnel_xmit+0x468/0x850 net/ipv4/ip_tunnel_core.c:80 udp_tunnel_xmit_skb+0x1ba/0x290 net/ipv4/udp_tunnel_core.c:190 send4+0x5d4/0xaf0 drivers/net/wireguard/socket.c:85 wg_socket_send_skb_to_peer+0xcd/0x1c0 drivers/net/wireguard/socket.c:175 wg_packet_send_handshake_initiation drivers/net/wireguard/send.c:40 [inline] wg_packet_handshake_send_worker+0x16b/0x280 drivers/net/wireguard/send.c:51 process_one_work+0x85e/0xff0 kernel/workqueue.c:2282 worker_thread+0xa9b/0x1430 kernel/workqueue.c:2428 kthread+0x386/0x410 kernel/kthread.c:328 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 Kernel Offset: disabled Rebooting in 86400 seconds.. Warning: Permanently added '10.128.1.176' (ED25519) to the list of known hosts. 2025/10/24 08:30:04 parsed 1 programs [ 48.013663][ T6013] cgroup: Unknown subsys name 'net' [ 48.170944][ T6013] cgroup: Unknown subsys name 'rlimit' [ 49.896812][ T6013] Adding 124996k swap on ./swap-file. Priority:0 extents:1 across:124996k [ 50.802412][ T6020] IPVS: ftp: loaded support on port[0] = 21 [ 50.981218][ T6026] IPVS: ftp: loaded support on port[0] = 21 [ 51.070963][ T6031] IPVS: ftp: loaded support on port[0] = 21 [ 51.212304][ T6037] IPVS: ftp: loaded support on port[0] = 21 [ 51.298209][ T6042] IPVS: ftp: loaded support on port[0] = 21 [ 51.396045][ T6047] IPVS: ftp: loaded support on port[0] = 21 [ 51.445463][ T6047] chnl_net:caif_netlink_parms(): no params data found [ 51.483834][ T6047] bridge0: port 1(bridge_slave_0) entered blocking state [ 51.491355][ T6047] bridge0: port 1(bridge_slave_0) entered disabled state [ 51.499426][ T6047] device bridge_slave_0 entered promiscuous mode [ 51.507218][ T6047] bridge0: port 2(bridge_slave_1) entered blocking state [ 51.514361][ T6047] bridge0: port 2(bridge_slave_1) entered disabled state [ 51.521916][ T6047] device bridge_slave_1 entered promiscuous mode [ 51.540701][ T6047] bond0: (slave bond_slave_0): Enslaving as an active interface with an up link [ 51.551842][ T6047] bond0: (slave bond_slave_1): Enslaving as an active interface with an up link [ 51.567750][ T6047] team0: Port device team_slave_0 added [ 51.574571][ T6047] team0: Port device team_slave_1 added [ 51.586442][ T6047] batman_adv: batadv0: Adding interface: batadv_slave_0 [ 51.593515][ T6047] 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 1532 would solve the problem. [ 51.619504][ T6047] batman_adv: batadv0: Not using interface batadv_slave_0 (retrying later): interface not active [ 51.631289][ T6047] batman_adv: batadv0: Adding interface: batadv_slave_1 [ 51.638275][ T6047] 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 1532 would solve the problem. [ 51.664460][ T6047] batman_adv: batadv0: Not using interface batadv_slave_1 (retrying later): interface not active [ 51.688501][ T6047] device hsr_slave_0 entered promiscuous mode [ 51.695170][ T6047] device hsr_slave_1 entered promiscuous mode [ 51.745737][ T6047] netdevsim netdevsim0 netdevsim0: renamed from eth0 [ 51.754100][ T6047] netdevsim netdevsim0 netdevsim1: renamed from eth1 [ 51.762823][ T6047] netdevsim netdevsim0 netdevsim2: renamed from eth2 [ 51.771249][ T6047] netdevsim netdevsim0 netdevsim3: renamed from eth3 [ 51.786410][ T6047] bridge0: port 2(bridge_slave_1) entered blocking state [ 51.793485][ T6047] bridge0: port 2(bridge_slave_1) entered forwarding state [ 51.800980][ T6047] bridge0: port 1(bridge_slave_0) entered blocking state [ 51.808073][ T6047] bridge0: port 1(bridge_slave_0) entered forwarding state [ 51.835190][ T6047] 8021q: adding VLAN 0 to HW filter on device bond0 [ 51.846473][ T178] IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready [ 51.855767][ T178] bridge0: port 1(bridge_slave_0) entered disabled state [ 51.863380][ T178] bridge0: port 2(bridge_slave_1) entered disabled state [ 51.871161][ T178] IPv6: ADDRCONF(NETDEV_CHANGE): bond0: link becomes ready [ 51.886989][ T6047] 8021q: adding VLAN 0 to HW filter on device team0 [ 51.896287][ T27] IPv6: ADDRCONF(NETDEV_CHANGE): bridge_slave_0: link becomes ready [ 51.904678][ T27] bridge0: port 1(bridge_slave_0) entered blocking state [ 51.911755][ T27] bridge0: port 1(bridge_slave_0) entered forwarding state [ 51.928140][ T27] IPv6: ADDRCONF(NETDEV_CHANGE): bridge_slave_1: link becomes ready [ 51.936459][ T27] bridge0: port 2(bridge_slave_1) entered blocking state [ 51.943545][ T27] bridge0: port 2(bridge_slave_1) entered forwarding state [ 51.951785][ T27] IPv6: ADDRCONF(NETDEV_CHANGE): team_slave_0: link becomes ready [ 51.968045][ T27] IPv6: ADDRCONF(NETDEV_CHANGE): team0: link becomes ready [ 51.976221][ T27] IPv6: ADDRCONF(NETDEV_CHANGE): team_slave_1: link becomes ready [ 51.986689][ T27] IPv6: ADDRCONF(NETDEV_CHANGE): hsr_slave_0: link becomes ready [ 51.997233][ T27] IPv6: ADDRCONF(NETDEV_CHANGE): hsr_slave_1: link becomes ready [ 52.007405][ T6047] IPv6: ADDRCONF(NETDEV_CHANGE): hsr0: link becomes ready [ 52.064410][ T27] IPv6: ADDRCONF(NETDEV_CHANGE): vxcan0: link becomes ready [ 52.072318][ T27] IPv6: ADDRCONF(NETDEV_CHANGE): vxcan1: link becomes ready [ 52.083417][ T6047] 8021q: adding VLAN 0 to HW filter on device batadv0 [ 52.097534][ T27] IPv6: ADDRCONF(NETDEV_CHANGE): veth0_virt_wifi: link becomes ready [ 52.116942][ T27] IPv6: ADDRCONF(NETDEV_CHANGE): veth0_vlan: link becomes ready [ 52.125424][ T27] IPv6: ADDRCONF(NETDEV_CHANGE): vlan0: link becomes ready [ 52.133639][ T27] IPv6: ADDRCONF(NETDEV_CHANGE): vlan1: link becomes ready [ 52.144186][ T6047] device veth0_vlan entered promiscuous mode [ 52.158944][ T6047] device veth1_vlan entered promiscuous mode [ 52.173076][ T27] IPv6: ADDRCONF(NETDEV_CHANGE): macvlan0: link becomes ready [ 52.181468][ T27] IPv6: ADDRCONF(NETDEV_CHANGE): macvlan1: link becomes ready [ 52.189866][ T27] IPv6: ADDRCONF(NETDEV_CHANGE): veth0_macvtap: link becomes ready [ 52.205170][ T6047] device veth0_macvtap entered promiscuous mode [ 52.213384][ T6047] device veth1_macvtap entered promiscuous mode [ 52.226086][ T6047] batman_adv: batadv0: Interface activated: batadv_slave_0 [ 52.233924][ T27] IPv6: ADDRCONF(NETDEV_CHANGE): veth0_to_batadv: link becomes ready [ 52.242748][ T27] IPv6: ADDRCONF(NETDEV_CHANGE): macvtap0: link becomes ready [ 52.257429][ T6047] batman_adv: batadv0: Interface activated: batadv_slave_1 [ 52.264976][ T178] IPv6: ADDRCONF(NETDEV_CHANGE): veth1_to_batadv: link becomes ready [ 52.275526][ T6047] netdevsim netdevsim0 netdevsim0: set [1, 0] type 2 family 0 port 6081 - 0 [ 52.284833][ T6047] netdevsim netdevsim0 netdevsim1: set [1, 0] type 2 family 0 port 6081 - 0 [ 52.293537][ T6047] netdevsim netdevsim0 netdevsim2: set [1, 0] type 2 family 0 port 6081 - 0 [ 52.302445][ T6047] netdevsim netdevsim0 netdevsim3: set [1, 0] type 2 family 0 port 6081 - 0 [ 52.318876][ T27] ================================================================================ [ 52.328195][ T27] UBSAN: signed-integer-overflow in ./arch/x86/include/asm/atomic.h:165:11 [ 52.336760][ T27] -1399202697 + -1961381633 cannot be represented in type 'int' [ 52.344421][ T27] CPU: 1 PID: 27 Comm: kworker/u4:2 Not tainted syzkaller #0 [ 52.351780][ T27] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 [ 52.361832][ T27] Workqueue: wg-kex-wg0 wg_packet_handshake_send_worker [ 52.368761][ T27] Call Trace: [ 52.372032][ T27] dump_stack+0xfd/0x16e [ 52.376247][ T27] ubsan_epilogue+0xa/0x30 [ 52.380663][ T27] handle_overflow+0x192/0x1b0 [ 52.385400][ T27] ? prandom_u32+0x217/0x260 [ 52.390240][ T27] ip_idents_reserve+0x14a/0x170 [ 52.395164][ T27] __ip_select_ident+0xe4/0x1c0 [ 52.400000][ T27] iptunnel_xmit+0x468/0x850 [ 52.404585][ T27] udp_tunnel_xmit_skb+0x1ba/0x290 [ 52.409691][ T27] send4+0x5d4/0xaf0 [ 52.413573][ T27] wg_socket_send_skb_to_peer+0xcd/0x1c0 [ 52.419181][ T27] wg_packet_handshake_send_worker+0x16b/0x280 [ 52.425312][ T27] process_one_work+0x85e/0xff0 [ 52.430173][ T27] worker_thread+0xa9b/0x1430 [ 52.434940][ T27] ? rcu_lock_release+0x20/0x20 [ 52.439765][ T27] kthread+0x386/0x410 [ 52.443809][ T27] ? rcu_lock_release+0x20/0x20 [ 52.448664][ T27] ? kthread_blkcg+0xd0/0xd0 [ 52.453322][ T27] ret_from_fork+0x1f/0x30 [ 52.457765][ T27] ================================================================================ [ 52.467065][ T27] Kernel panic - not syncing: UBSAN: panic_on_warn set ... [ 52.474261][ T27] CPU: 1 PID: 27 Comm: kworker/u4:2 Not tainted syzkaller #0 [ 52.481603][ T27] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 [ 52.491670][ T27] Workqueue: wg-kex-wg0 wg_packet_handshake_send_worker [ 52.498580][ T27] Call Trace: [ 52.501854][ T27] dump_stack+0xfd/0x16e [ 52.506080][ T27] panic+0x2f0/0x9c0 [ 52.509954][ T27] check_panic_on_warn+0x95/0xe0 [ 52.514870][ T27] handle_overflow+0x192/0x1b0 [ 52.519633][ T27] ? prandom_u32+0x217/0x260 [ 52.524228][ T27] ip_idents_reserve+0x14a/0x170 [ 52.529235][ T27] __ip_select_ident+0xe4/0x1c0 [ 52.534066][ T27] iptunnel_xmit+0x468/0x850 [ 52.538633][ T27] udp_tunnel_xmit_skb+0x1ba/0x290 [ 52.543721][ T27] send4+0x5d4/0xaf0 [ 52.547604][ T27] wg_socket_send_skb_to_peer+0xcd/0x1c0 [ 52.553417][ T27] wg_packet_handshake_send_worker+0x16b/0x280 [ 52.559562][ T27] process_one_work+0x85e/0xff0 [ 52.564387][ T27] worker_thread+0xa9b/0x1430 [ 52.569136][ T27] ? rcu_lock_release+0x20/0x20 [ 52.574052][ T27] kthread+0x386/0x410 [ 52.578096][ T27] ? rcu_lock_release+0x20/0x20 [ 52.582913][ T27] ? kthread_blkcg+0xd0/0xd0 [ 52.587475][ T27] ret_from_fork+0x1f/0x30 [ 52.592191][ T27] Kernel Offset: disabled [ 52.596510][ T27] 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-build1315598195=/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 b6605ba8b96 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}}' -ldflags="-s -w -X github.com/google/syzkaller/prog.GitRevision=b6605ba8b96835063c5eb766c38d27fac98b84d4 -X github.com/google/syzkaller/prog.gitRevisionDate=20251013-102005" ./sys/syz-sysgen | grep -q false || go install -ldflags="-s -w -X github.com/google/syzkaller/prog.GitRevision=b6605ba8b96835063c5eb766c38d27fac98b84d4 -X github.com/google/syzkaller/prog.gitRevisionDate=20251013-102005" ./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=b6605ba8b96835063c5eb766c38d27fac98b84d4 -X github.com/google/syzkaller/prog.gitRevisionDate=20251013-102005" -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=\"b6605ba8b96835063c5eb766c38d27fac98b84d4\" /usr/bin/ld: /tmp/cccF2O1E.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 ./tools/check-syzos.sh 2>/dev/null