Oops: divide error: 0000 [#1] SMP KASAN NOPTI CPU: 0 UID: 0 PID: 14420 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 RIP: 0010:comedi_buf_munge drivers/comedi/comedi_buf.c:347 [inline] RIP: 0010:comedi_buf_write_free+0x3c8/0x7e0 drivers/comedi/comedi_buf.c:391 Code: 41 03 45 00 48 8b 4c 24 78 42 0f b6 0c 21 84 c9 4c 8b bc 24 90 00 00 00 44 8b 74 24 54 0f 85 02 01 00 00 31 d2 48 8b 4c 24 30 31 41 89 55 00 48 8b 44 24 70 42 0f b6 04 20 84 c0 0f 85 09 01 RSP: 0018:ffffc90000007bd8 EFLAGS: 00010046 RAX: 0000000000000001 RBX: dffffc0000000000 RCX: ffff88807e5b4a80 RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff888054779000 RBP: 0000000000000002 R08: 0000000000000000 R09: 1ffff1100a8ef200 R10: dffffc0000000000 R11: ffffffff88ad3dc0 R12: dffffc0000000000 R13: ffff88807e5b4a38 R14: 0000000000000000 R15: ffff88807e5b4a00 FS: 000055557e243500(0000) GS:ffff888126396000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f2088771000 CR3: 0000000077bcc000 CR4: 0000000000350ef0 Call Trace: comedi_buf_write_samples+0x369/0x5a0 drivers/comedi/comedi_buf.c:602 das16m1_handler+0x213/0x4b0 drivers/comedi/drivers/das16m1.c:413 das16m1_interrupt+0xaf/0x180 drivers/comedi/drivers/das16m1.c:470 __handle_irq_event_percpu+0x295/0xab0 kernel/irq/handle.c:203 handle_irq_event_percpu kernel/irq/handle.c:240 [inline] handle_irq_event+0x8b/0x1e0 kernel/irq/handle.c:257 handle_edge_irq+0x23b/0xa10 kernel/irq/chip.c:855 generic_handle_irq_desc include/linux/irqdesc.h:173 [inline] handle_irq arch/x86/kernel/irq.c:254 [inline] call_irq_handler arch/x86/kernel/irq.c:-1 [inline] __common_interrupt+0x141/0x1f0 arch/x86/kernel/irq.c:325 common_interrupt+0xb6/0xe0 arch/x86/kernel/irq.c:318 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693 RIP: 0010:rcu_lock_acquire include/linux/rcupdate.h:331 [inline] RIP: 0010:rcu_read_lock include/linux/rcupdate.h:841 [inline] RIP: 0010:class_rcu_constructor include/linux/rcupdate.h:1169 [inline] RIP: 0010:is_module_text_address+0x1d/0x1e0 kernel/module/main.c:3845 Code: 90 90 90 90 90 90 90 90 90 90 90 90 90 66 0f 1f 00 55 41 57 41 56 41 55 41 54 53 49 89 fe e8 6a 62 fc ff 48 8d 1d 00 00 00 00 <48> c7 c7 60 b1 d3 8d 31 f6 31 d2 b9 02 00 00 00 45 31 c0 45 31 c9 RSP: 0018:ffffc9000ebede00 EFLAGS: 00000283 RAX: 0000000000000002 RBX: ffffffff81a9719d RCX: dffffc0000000000 RDX: 0000000000000000 RSI: ffffffff8b9ec240 RDI: 00007f61d2990d5c RBP: 0000000000000001 R08: 0000000000000022 R09: ffffffff81725d45 R10: dffffc0000000000 R11: ffffffff81aaf9d0 R12: ffff8880267dbc80 R13: 00000000000002c0 R14: 00007f61d2990d5c R15: 1ffff92001d7dbda kernel_text_address+0x94/0xe0 kernel/extable.c:119 __kernel_text_address+0xd/0x40 kernel/extable.c:79 unwind_get_return_address+0x4d/0x90 arch/x86/kernel/unwind_orc.c:369 arch_stack_walk+0xfc/0x150 arch/x86/kernel/stacktrace.c:26 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 unpoison_slab_object mm/kasan/common.c:342 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:368 kasan_slab_alloc include/linux/kasan.h:252 [inline] slab_post_alloc_hook mm/slub.c:4946 [inline] slab_alloc_node mm/slub.c:5245 [inline] kmem_cache_alloc_node_noprof+0x433/0x710 mm/slub.c:5297 kmalloc_reserve+0xbd/0x290 net/core/skbuff.c:579 __alloc_skb+0x142/0x2d0 net/core/skbuff.c:670 alloc_skb include/linux/skbuff.h:1383 [inline] nlmsg_new include/net/netlink.h:1055 [inline] inet6_rt_notify+0x170/0x470 net/ipv6/route.c:6345 fib6_add_rt2node+0x1876/0x33a0 net/ipv6/ip6_fib.c:1275 fib6_add+0x8da/0x18a0 net/ipv6/ip6_fib.c:1528 __ip6_ins_rt net/ipv6/route.c:1351 [inline] ip6_route_add+0xde/0x1b0 net/ipv6/route.c:3946 addrconf_prefix_route net/ipv6/addrconf.c:2488 [inline] addrconf_add_linklocal+0x45f/0x6c0 net/ipv6/addrconf.c:3313 addrconf_addr_gen+0x490/0x580 net/ipv6/addrconf.c:3442 addrconf_init_auto_addrs+0x62d/0xa30 net/ipv6/addrconf.c:-1 addrconf_notify+0xacc/0x1010 net/ipv6/addrconf.c:3740 notifier_call_chain+0x1b6/0x3e0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2267 [inline] call_netdevice_notifiers net/core/dev.c:2281 [inline] __dev_notify_flags+0x18d/0x2e0 net/core/dev.c:-1 netif_change_flags+0xe8/0x1a0 net/core/dev.c:9705 do_setlink+0xc55/0x41c0 net/core/rtnetlink.c:3151 rtnl_changelink net/core/rtnetlink.c:3769 [inline] __rtnl_newlink net/core/rtnetlink.c:3928 [inline] rtnl_newlink+0x1619/0x1c80 net/core/rtnetlink.c:4065 rtnetlink_rcv_msg+0x7cf/0xb70 net/core/rtnetlink.c:6954 netlink_rcv_skb+0x208/0x470 net/netlink/af_netlink.c:2552 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x82f/0x9e0 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1896 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg+0x21c/0x270 net/socket.c:742 __sys_sendto+0x3bd/0x520 net/socket.c:2244 __do_sys_sendto net/socket.c:2251 [inline] __se_sys_sendto net/socket.c:2247 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2247 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: 0033:0x7f61d2990d5c Code: 2a 5f 02 00 44 8b 4c 24 2c 4c 8b 44 24 20 89 c5 44 8b 54 24 28 48 8b 54 24 18 b8 2c 00 00 00 48 8b 74 24 10 8b 7c 24 08 0f 05 <48> 3d 00 f0 ff ff 77 34 89 ef 48 89 44 24 08 e8 70 5f 02 00 48 8b RSP: 002b:00007ffd6d4664c0 EFLAGS: 00000293 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007f61d3714620 RCX: 00007f61d2990d5c RDX: 0000000000000020 RSI: 00007f61d3714670 RDI: 0000000000000003 RBP: 0000000000000000 R08: 00007ffd6d466514 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000003 R13: 0000000000000000 R14: 00007f61d3714670 R15: 0000000000000000 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:comedi_buf_munge drivers/comedi/comedi_buf.c:347 [inline] RIP: 0010:comedi_buf_write_free+0x3c8/0x7e0 drivers/comedi/comedi_buf.c:391 Code: 41 03 45 00 48 8b 4c 24 78 42 0f b6 0c 21 84 c9 4c 8b bc 24 90 00 00 00 44 8b 74 24 54 0f 85 02 01 00 00 31 d2 48 8b 4c 24 30 31 41 89 55 00 48 8b 44 24 70 42 0f b6 04 20 84 c0 0f 85 09 01 RSP: 0018:ffffc90000007bd8 EFLAGS: 00010046 RAX: 0000000000000001 RBX: dffffc0000000000 RCX: ffff88807e5b4a80 RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff888054779000 RBP: 0000000000000002 R08: 0000000000000000 R09: 1ffff1100a8ef200 R10: dffffc0000000000 R11: ffffffff88ad3dc0 R12: dffffc0000000000 R13: ffff88807e5b4a38 R14: 0000000000000000 R15: ffff88807e5b4a00 FS: 000055557e243500(0000) GS:ffff888126396000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f2088771000 CR3: 0000000077bcc000 CR4: 0000000000350ef0 ---------------- Code disassembly (best guess): 0: 41 03 45 00 add 0x0(%r13),%eax 4: 48 8b 4c 24 78 mov 0x78(%rsp),%rcx 9: 42 0f b6 0c 21 movzbl (%rcx,%r12,1),%ecx e: 84 c9 test %cl,%cl 10: 4c 8b bc 24 90 00 00 mov 0x90(%rsp),%r15 17: 00 18: 44 8b 74 24 54 mov 0x54(%rsp),%r14d 1d: 0f 85 02 01 00 00 jne 0x125 23: 31 d2 xor %edx,%edx 25: 48 8b 4c 24 30 mov 0x30(%rsp),%rcx * 2a: f7 31 divl (%rcx) <-- trapping instruction 2c: 41 89 55 00 mov %edx,0x0(%r13) 30: 48 8b 44 24 70 mov 0x70(%rsp),%rax 35: 42 0f b6 04 20 movzbl (%rax,%r12,1),%eax 3a: 84 c0 test %al,%al 3c: 0f .byte 0xf 3d: 85 09 test %ecx,(%rcx) 3f: 01 .byte 0x1