Hello, syzbot found the following issue on:
HEAD commit: e728258debd5 Merge tag 'net-7.1-rc1' of git://git.kernel.o.. git tree: net-next console output: https://syzkaller.appspot.com/x/log.txt?x=169022ce580000 kernel config: https://syzkaller.appspot.com/x/.config?x=ca77bfc4078c8193 dashboard link: https://syzkaller.appspot.com/bug?extid=217f1db9c791e27fe54a compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/24195bde5d1d/disk-e728258d.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/78131d1b0e14/vmlinux-e728258d.xz kernel image: https://storage.googleapis.com/syzbot-assets/836d0dd78c10/bzImage-e728258d.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: [email protected] wlan0: No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge) ------------[ cut here ]------------ UBSAN: shift-out-of-bounds in ./include/linux/log2.h:57:13 shift exponent 64 is too large for 64-bit type 'unsigned long' CPU: 1 UID: 0 PID: 77 Comm: kworker/u8:4 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 Workqueue: events_unbound conn_resize_work_handler Call Trace: <TASK> dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 ubsan_epilogue+0xa/0x30 lib/ubsan.c:233 __ubsan_handle_shift_out_of_bounds+0x385/0x410 lib/ubsan.c:494 __roundup_pow_of_two include/linux/log2.h:57 [inline] ip_vs_rht_desired_size+0x2cf/0x410 net/netfilter/ipvs/ip_vs_core.c:240 ip_vs_conn_desired_size net/netfilter/ipvs/ip_vs_conn.c:765 [inline] conn_resize_work_handler+0x1b6/0x14c0 net/netfilter/ipvs/ip_vs_conn.c:822 process_one_work kernel/workqueue.c:3302 [inline] process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3385 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3466 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 </TASK> ---[ end trace ]--- Kernel panic - not syncing: UBSAN: panic_on_warn set ... CPU: 1 UID: 0 PID: 77 Comm: kworker/u8:4 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 Workqueue: events_unbound conn_resize_work_handler Call Trace: <TASK> vpanic+0x56c/0xa60 kernel/panic.c:650 panic+0xc5/0xd0 kernel/panic.c:787 check_panic_on_warn+0x89/0xb0 kernel/panic.c:524 __ubsan_handle_shift_out_of_bounds+0x385/0x410 lib/ubsan.c:494 __roundup_pow_of_two include/linux/log2.h:57 [inline] ip_vs_rht_desired_size+0x2cf/0x410 net/netfilter/ipvs/ip_vs_core.c:240 ip_vs_conn_desired_size net/netfilter/ipvs/ip_vs_conn.c:765 [inline] conn_resize_work_handler+0x1b6/0x14c0 net/netfilter/ipvs/ip_vs_conn.c:822 process_one_work kernel/workqueue.c:3302 [inline] process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3385 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3466 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 </TASK> Kernel Offset: disabled Rebooting in 86400 seconds.. --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at [email protected]. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. If the report is already addressed, let syzbot know by replying with: #syz fix: exact-commit-title If you want to overwrite report's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the report is a duplicate of another one, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup
