------------[ cut here ]------------ WARNING: CPU: 0 PID: 7907 at net/ipv4/ipmr.c:2302 ip_mr_output+0xbb1/0xe70 net/ipv4/ipmr.c:2302 Modules linked in: CPU: 0 UID: 0 PID: 7907 Comm: syz.4.593 Not tainted 6.16.0-rc2-syzkaller-00591-g4f4040ea5d3e #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 ce 33 c6 f7 48 8b 74 24 18 45 31 f6 31 ff ba 02 00 00 00 e8 9a 09 4c ff e9 45 f6 ff ff e8 b0 33 c6 f7 90 <0f> 0b 90 e9 94 f5 ff ff e8 a2 33 c6 f7 90 0f 0b 90 42 80 3c 2b 00 RSP: 0018:ffffc90000007900 EFLAGS: 00010246 RAX: ffffffff89fa28a0 RBX: ffff88807dc3ec80 RCX: ffff88802bf13c00 RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90000007a10 R08: ffff88802bf13c00 R09: 0000000000000004 R10: 0000000000000003 R11: ffffffff89fa1cf0 R12: 0000000000000010 R13: dffffc0000000000 R14: ffff8880332ff000 R15: 0000000000000000 FS: 00007fa43b6646c0(0000) GS:ffff888125c4f000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa65731e1e6 CR3: 00000000778b8000 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 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1050 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:constant_test_bit arch/x86/include/asm/bitops.h:-1 [inline] RIP: 0010:arch_test_bit arch/x86/include/asm/bitops.h:238 [inline] RIP: 0010:_test_bit include/asm-generic/bitops/instrumented-non-atomic.h:142 [inline] RIP: 0010:folio_test_head include/linux/page-flags.h:867 [inline] RIP: 0010:folio_test_large include/linux/page-flags.h:888 [inline] RIP: 0010:folio_nr_pages include/linux/mm.h:1976 [inline] RIP: 0010:charge_memcg+0x63/0x180 mm/memcontrol.c:4770 Code: 01 0f 85 12 01 00 00 48 89 df be 08 00 00 00 e8 43 ba f7 ff 48 89 d8 48 c1 e8 03 42 80 3c 20 00 74 08 48 89 df e8 bd b7 f7 ff 01 00 00 00 48 f7 03 40 00 00 00 74 1b 4c 8d 7b 78 4c 89 f8 48 RSP: 0018:ffffc90005107488 EFLAGS: 00000246 RAX: 1ffffd40000d0578 RBX: ffffea0000682bc0 RCX: ffffffff822c229d RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffea0000682bc0 RBP: 0000000000000cc0 R08: ffffea0000682bc7 R09: 1ffffd40000d0578 R10: dffffc0000000000 R11: fffff940000d0579 R12: dffffc0000000000 R13: ffffea0000682bc0 R14: ffff8880286e9a00 R15: ffffea0000682bc8 __mem_cgroup_charge+0x25/0x80 mm/memcontrol.c:4787 mem_cgroup_charge include/linux/memcontrol.h:652 [inline] shmem_alloc_and_add_folio+0x7c1/0xf60 mm/shmem.c:1900 shmem_get_folio_gfp+0x59d/0x1660 mm/shmem.c:2532 shmem_fault+0x179/0x390 mm/shmem.c:2733 __do_fault+0x138/0x390 mm/memory.c:5189 do_read_fault mm/memory.c:5610 [inline] do_fault mm/memory.c:5744 [inline] do_pte_missing mm/memory.c:4251 [inline] handle_pte_fault mm/memory.c:6089 [inline] __handle_mm_fault+0x37ed/0x5620 mm/memory.c:6232 handle_mm_fault+0x40a/0x8e0 mm/memory.c:6401 faultin_page mm/gup.c:1186 [inline] __get_user_pages+0x1af4/0x30b0 mm/gup.c:1488 populate_vma_page_range+0x26b/0x340 mm/gup.c:1926 __mm_populate+0x24c/0x380 mm/gup.c:2029 mm_populate include/linux/mm.h:3348 [inline] vm_mmap_pgoff+0x3f0/0x4c0 mm/util.c:584 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fa43a78e929 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fa43b664038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007fa43a9b6080 RCX: 00007fa43a78e929 RDX: b635773f05ebbee1 RSI: 0000000000b36000 RDI: 0000200000000000 RBP: 00007fa43a810b39 R08: ffffffffffffffff R09: 0000000000000000 R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fa43a9b6080 R15: 00007ffc14fcd988 ---------------- Code disassembly (best guess): 0: 01 0f add %ecx,(%rdi) 2: 85 12 test %edx,(%rdx) 4: 01 00 add %eax,(%rax) 6: 00 48 89 add %cl,-0x77(%rax) 9: df be 08 00 00 00 fistpll 0x8(%rsi) f: e8 43 ba f7 ff call 0xfff7ba57 14: 48 89 d8 mov %rbx,%rax 17: 48 c1 e8 03 shr $0x3,%rax 1b: 42 80 3c 20 00 cmpb $0x0,(%rax,%r12,1) 20: 74 08 je 0x2a 22: 48 89 df mov %rbx,%rdi 25: e8 bd b7 f7 ff call 0xfff7b7e7 * 2a: ba 01 00 00 00 mov $0x1,%edx <-- trapping instruction 2f: 48 f7 03 40 00 00 00 testq $0x40,(%rbx) 36: 74 1b je 0x53 38: 4c 8d 7b 78 lea 0x78(%rbx),%r15 3c: 4c 89 f8 mov %r15,%rax 3f: 48 rex.W