================================================================================ UBSAN: signed-integer-overflow in ./arch/x86/include/asm/atomic.h:165:11 -2082307266 + -1738913672 cannot be represented in type 'int' CPU: 0 PID: 43 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+0x466/0x7b0 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+0x85c/0xfa0 kernel/workqueue.c:2282 worker_thread+0xa9b/0x1430 kernel/workqueue.c:2428 kthread+0x360/0x3e0 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: 0 PID: 43 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+0x466/0x7b0 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+0x85c/0xfa0 kernel/workqueue.c:2282 worker_thread+0xa9b/0x1430 kernel/workqueue.c:2428 kthread+0x360/0x3e0 kernel/kthread.c:328 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 Kernel Offset: disabled Rebooting in 86400 seconds..