comedi comedi3: c6xdigio: I/O port conflict (0x4f24,3) ================================================================== BUG: KASAN: slab-use-after-free in sysfs_remove_file_ns+0x3d/0x70 fs/sysfs/file.c:510 Read of size 8 at addr ffff88803474f030 by task syz.0.5632/25201 CPU: 0 UID: 0 PID: 25201 Comm: syz.0.5632 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xca/0x240 mm/kasan/report.c:482 kasan_report+0x118/0x150 mm/kasan/report.c:595 sysfs_remove_file_ns+0x3d/0x70 fs/sysfs/file.c:510 remove_bind_files drivers/base/bus.c:643 [inline] bus_remove_driver+0x198/0x320 drivers/base/bus.c:781 comedi_device_detach_locked+0x178/0x750 drivers/comedi/drivers.c:207 comedi_device_detach drivers/comedi/drivers.c:215 [inline] comedi_device_attach+0x5d4/0x720 drivers/comedi/drivers.c:1011 do_devconfig_ioctl drivers/comedi/comedi_fops.c:872 [inline] comedi_unlocked_ioctl+0x645/0x1020 drivers/comedi/comedi_fops.c:2178 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fe3c678f749 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:00007fe3c76ad038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fe3c69e5fa0 RCX: 00007fe3c678f749 RDX: 00002000000000c0 RSI: 0000000040946400 RDI: 0000000000000006 RBP: 00007fe3c6813f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fe3c69e6038 R14: 00007fe3c69e5fa0 R15: 00007fffa03146e8 Allocated by task 23943: kasan_save_stack mm/kasan/common.c:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 poison_kmalloc_redzone mm/kasan/common.c:397 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:414 kasan_kmalloc include/linux/kasan.h:262 [inline] __do_kmalloc_node mm/slub.c:5652 [inline] __kmalloc_noprof+0x41d/0x800 mm/slub.c:5664 kmalloc_noprof include/linux/slab.h:961 [inline] kzalloc_noprof include/linux/slab.h:1094 [inline] fib_create_info+0x171d/0x3220 net/ipv4/fib_semantics.c:1402 fib_table_insert+0xca/0x1b80 net/ipv4/fib_trie.c:1212 fib_magic+0x2c4/0x390 net/ipv4/fib_frontend.c:1134 fib_add_ifaddr+0x144/0x5f0 net/ipv4/fib_frontend.c:1156 fib_netdev_event+0x382/0x490 net/ipv4/fib_frontend.c:1516 notifier_call_chain+0x19d/0x3d0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2269 [inline] call_netdevice_notifiers net/core/dev.c:2283 [inline] __dev_notify_flags+0x18d/0x2e0 net/core/dev.c:-1 netif_change_flags+0xe8/0x1a0 net/core/dev.c:9795 do_setlink+0xc55/0x41c0 net/core/rtnetlink.c:3158 rtnl_changelink net/core/rtnetlink.c:3776 [inline] __rtnl_newlink net/core/rtnetlink.c:3935 [inline] rtnl_newlink+0x161c/0x1c90 net/core/rtnetlink.c:4072 rtnetlink_rcv_msg+0x7cf/0xb70 net/core/rtnetlink.c:6958 netlink_rcv_skb+0x208/0x470 net/netlink/af_netlink.c:2550 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x82f/0x9e0 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1894 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg+0x21c/0x270 net/socket.c:746 __sys_sendto+0x3bd/0x520 net/socket.c:2248 __do_sys_sendto net/socket.c:2255 [inline] __se_sys_sendto net/socket.c:2251 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2251 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 3528: kasan_save_stack mm/kasan/common.c:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:252 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:284 kasan_slab_free include/linux/kasan.h:234 [inline] slab_free_hook mm/slub.c:2540 [inline] slab_free mm/slub.c:6663 [inline] kfree+0x1c0/0x680 mm/slub.c:6871 rcu_do_batch kernel/rcu/tree.c:2605 [inline] rcu_core+0xcab/0x1770 kernel/rcu/tree.c:2861 handle_softirqs+0x27d/0x880 kernel/softirq.c:626 do_softirq+0xec/0x180 kernel/softirq.c:523 __local_bh_enable_ip+0x17d/0x1c0 kernel/softirq.c:450 spin_unlock_bh include/linux/spinlock.h:396 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:835 [inline] nsim_dev_trap_report_work+0x7c7/0xb80 drivers/net/netdevsim/dev.c:866 process_one_work+0x93a/0x15e0 kernel/workqueue.c:3261 process_scheduled_works kernel/workqueue.c:3344 [inline] worker_thread+0x9b0/0xee0 kernel/workqueue.c:3425 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:56 kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:556 __call_rcu_common kernel/rcu/tree.c:3123 [inline] call_rcu+0x157/0x9c0 kernel/rcu/tree.c:3243 fib_create_info+0x258d/0x3220 net/ipv4/fib_semantics.c:1536 fib_table_insert+0xca/0x1b80 net/ipv4/fib_trie.c:1212 fib_magic+0x2c4/0x390 net/ipv4/fib_frontend.c:1134 fib_add_ifaddr+0x144/0x5f0 net/ipv4/fib_frontend.c:1156 fib_netdev_event+0x382/0x490 net/ipv4/fib_frontend.c:1516 notifier_call_chain+0x19d/0x3d0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2269 [inline] call_netdevice_notifiers net/core/dev.c:2283 [inline] __dev_notify_flags+0x18d/0x2e0 net/core/dev.c:-1 netif_change_flags+0xe8/0x1a0 net/core/dev.c:9795 do_setlink+0xc55/0x41c0 net/core/rtnetlink.c:3158 rtnl_changelink net/core/rtnetlink.c:3776 [inline] __rtnl_newlink net/core/rtnetlink.c:3935 [inline] rtnl_newlink+0x161c/0x1c90 net/core/rtnetlink.c:4072 rtnetlink_rcv_msg+0x7cf/0xb70 net/core/rtnetlink.c:6958 netlink_rcv_skb+0x208/0x470 net/netlink/af_netlink.c:2550 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x82f/0x9e0 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1894 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg+0x21c/0x270 net/socket.c:746 __sys_sendto+0x3bd/0x520 net/socket.c:2248 __do_sys_sendto net/socket.c:2255 [inline] __se_sys_sendto net/socket.c:2251 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2251 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88803474f000 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 48 bytes inside of freed 256-byte region [ffff88803474f000, ffff88803474f100) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88803474f000 pfn:0x3474e head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000240(workingset|head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000240 ffff88813fe26b40 ffffea0000c7bf10 ffffea0000cd0610 raw: ffff88803474f000 000000000010000f 00000000f5000000 0000000000000000 head: 00fff00000000240 ffff88813fe26b40 ffffea0000c7bf10 ffffea0000cd0610 head: ffff88803474f000 000000000010000f 00000000f5000000 0000000000000000 head: 00fff00000000001 ffffea0000d1d381 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000002 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 1, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5825, tgid 5825 (syz-executor), ts 96786846855, free_ts 96707287880 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x234/0x290 mm/page_alloc.c:1846 prep_new_page mm/page_alloc.c:1854 [inline] get_page_from_freelist+0x2365/0x2440 mm/page_alloc.c:3915 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5210 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2486 alloc_slab_page mm/slub.c:3075 [inline] allocate_slab+0x86/0x3b0 mm/slub.c:3248 new_slab mm/slub.c:3302 [inline] ___slab_alloc+0xf56/0x1990 mm/slub.c:4651 __slab_alloc+0x65/0x100 mm/slub.c:4774 __slab_alloc_node mm/slub.c:4850 [inline] slab_alloc_node mm/slub.c:5246 [inline] __do_kmalloc_node mm/slub.c:5651 [inline] __kmalloc_noprof+0x47d/0x800 mm/slub.c:5664 kmalloc_noprof include/linux/slab.h:961 [inline] kzalloc_noprof include/linux/slab.h:1094 [inline] new_dir fs/proc/proc_sysctl.c:966 [inline] get_subdir fs/proc/proc_sysctl.c:1010 [inline] sysctl_mkdir_p fs/proc/proc_sysctl.c:1320 [inline] __register_sysctl_table+0xba1/0x1340 fs/proc/proc_sysctl.c:1395 __addrconf_sysctl_register+0x328/0x4c0 net/ipv6/addrconf.c:7323 addrconf_sysctl_register+0x168/0x1c0 net/ipv6/addrconf.c:7371 ipv6_add_dev+0xd44/0x1410 net/ipv6/addrconf.c:460 addrconf_notify+0x771/0x1080 net/ipv6/addrconf.c:3650 notifier_call_chain+0x19d/0x3d0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2269 [inline] call_netdevice_notifiers net/core/dev.c:2283 [inline] register_netdevice+0x15fd/0x1b00 net/core/dev.c:11422 macvlan_common_newlink+0x120a/0x1980 drivers/net/macvlan.c:1540 page last free pid 5836 tgid 5836 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1395 [inline] __free_frozen_pages+0xbc8/0xd30 mm/page_alloc.c:2943 __slab_free+0x21b/0x2a0 mm/slub.c:5999 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x97/0x100 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:349 kasan_slab_alloc include/linux/kasan.h:252 [inline] slab_post_alloc_hook mm/slub.c:4948 [inline] slab_alloc_node mm/slub.c:5258 [inline] __kmalloc_cache_noprof+0x37c/0x700 mm/slub.c:5766 kmalloc_noprof include/linux/slab.h:957 [inline] kzalloc_noprof include/linux/slab.h:1094 [inline] mca_alloc net/ipv6/mcast.c:871 [inline] __ipv6_dev_mc_inc+0x44f/0xa50 net/ipv6/mcast.c:961 ipv6_add_dev+0xe52/0x1410 net/ipv6/addrconf.c:472 addrconf_notify+0x771/0x1080 net/ipv6/addrconf.c:3650 notifier_call_chain+0x19d/0x3d0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2269 [inline] call_netdevice_notifiers net/core/dev.c:2283 [inline] register_netdevice+0x15fd/0x1b00 net/core/dev.c:11422 register_vlan_dev+0x391/0x830 net/8021q/vlan.c:179 vlan_newlink+0x4b2/0x610 net/8021q/vlan_netlink.c:194 rtnl_newlink_create+0x310/0xb00 net/core/rtnetlink.c:3840 __rtnl_newlink net/core/rtnetlink.c:3957 [inline] rtnl_newlink+0x16e7/0x1c90 net/core/rtnetlink.c:4072 rtnetlink_rcv_msg+0x7cf/0xb70 net/core/rtnetlink.c:6958 Memory state around the buggy address: ffff88803474ef00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88803474ef80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88803474f000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88803474f080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88803474f100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================