------------[ cut here ]------------ WARNING: net/ipv4/ipmr.c:2302 at ip_mr_output+0xbb1/0xe70 net/ipv4/ipmr.c:2302, CPU#1: ksoftirqd/1/23 Modules linked in: CPU: 1 UID: 0 PID: 23 Comm: ksoftirqd/1 Not tainted 6.16.0-rc2-next-20250620-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:ip_mr_output+0xbb1/0xe70 net/ipv4/ipmr.c:2302 Code: df e9 63 f6 ff ff e8 2e 47 bf f7 48 8b 74 24 18 45 31 f6 31 ff ba 02 00 00 00 e8 1a 08 4c ff e9 45 f6 ff ff e8 10 47 bf f7 90 <0f> 0b 90 e9 94 f5 ff ff e8 02 47 bf f7 90 0f 0b 90 42 80 3c 2b 00 RSP: 0018:ffffc900001d7620 EFLAGS: 00010246 RAX: ffffffff8a0111d0 RBX: ffff88804cf06280 RCX: ffff88801d2fda00 RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc900001d7730 R08: ffff88801d2fda00 R09: 0000000000000004 R10: 0000000000000003 R11: ffffffff8a010620 R12: 0000000000000010 R13: dffffc0000000000 R14: ffff888046c83c00 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff888125d26000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c2bbb55 CR3: 0000000076ed8000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: igmp_send_report+0x89e/0xdb0 net/ipv4/igmp.c:799 igmp_timer_expire+0x204/0x510 net/ipv4/igmp.c:-1 call_timer_fn+0x17e/0x5f0 kernel/time/timer.c:1747 expire_timers kernel/time/timer.c:1798 [inline] __run_timers kernel/time/timer.c:2372 [inline] __run_timer_base+0x61a/0x860 kernel/time/timer.c:2384 run_timer_base kernel/time/timer.c:2393 [inline] run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2403 handle_softirqs+0x286/0x870 kernel/softirq.c:579 run_ksoftirqd+0x9b/0x100 kernel/softirq.c:968 smpboot_thread_fn+0x53f/0xa60 kernel/smpboot.c:160 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245