RAX: ffffffffffffffda RBX: 00007f6383455fa0 RCX: 00007f63831feec9 RDX: 00002000000000c0 RSI: 0000000040946400 RDI: 0000000000000003 RBP: 00007f638145e090 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007f6383456038 R14: 00007f6383455fa0 R15: 00007ffd5aa4e3a8 comedi comedi3: c6xdigio: I/O port conflict (0x4f27,3) ================================================================== BUG: KASAN: slab-use-after-free in sysfs_remove_file_ns+0x3d/0x70 fs/sysfs/file.c:510 Read of size 8 at addr ffff8880580e4830 by task syz.4.2153/11932 CPU: 0 UID: 0 PID: 11932 Comm: syz.4.2153 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 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:605 [inline] bus_remove_driver+0x19b/0x300 drivers/base/bus.c:743 comedi_device_detach_locked+0x175/0x750 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+0x605/0x1020 drivers/comedi/comedi_fops.c:2178 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl+0xff/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: 0033:0x7f63831feec9 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:00007f638145e038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f6383455fa0 RCX: 00007f63831feec9 RDX: 00002000000000c0 RSI: 0000000040946400 RDI: 0000000000000003 RBP: 00007f638145e090 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007f6383456038 R14: 00007f6383455fa0 R15: 00007ffd5aa4e3a8 Allocated by task 11127: 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:400 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:417 kasan_kmalloc include/linux/kasan.h:262 [inline] __kmalloc_cache_noprof+0x1ef/0x6c0 mm/slub.c:5725 kmalloc_noprof include/linux/slab.h:957 [inline] tipc_sub_subscribe+0x118/0x6a0 net/tipc/subscr.c:146 tipc_conn_rcv_sub+0x134/0x370 net/tipc/topsrv.c:378 tipc_topsrv_kern_subscr+0x17b/0x240 net/tipc/topsrv.c:592 tipc_group_create+0x364/0x500 net/tipc/group.c:190 tipc_sk_join+0x24d/0x6b0 net/tipc/socket.c:3083 tipc_setsockopt+0x735/0x970 net/tipc/socket.c:3200 do_sock_setsockopt+0x17c/0x1b0 net/socket.c:2360 __sys_setsockopt net/socket.c:2385 [inline] __do_sys_setsockopt net/socket.c:2391 [inline] __se_sys_setsockopt net/socket.c:2388 [inline] __x64_sys_setsockopt+0x145/0x1b0 net/socket.c:2388 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 11125: 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:587 kasan_save_free_info mm/kasan/kasan.h:406 [inline] 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:2515 [inline] slab_free mm/slub.c:6574 [inline] kfree+0x197/0x950 mm/slub.c:6781 tipc_conn_delete_sub+0x13c/0x1c0 net/tipc/topsrv.c:240 tipc_topsrv_kern_unsubscr+0x8b/0xb0 net/tipc/topsrv.c:609 tipc_group_delete+0x412/0x480 net/tipc/group.c:228 tipc_sk_leave+0x138/0x4e0 net/tipc/socket.c:3118 tipc_release+0x5fc/0x21b0 net/tipc/socket.c:642 __sock_release net/socket.c:662 [inline] sock_close+0xc0/0x240 net/socket.c:1455 __fput+0x45b/0xa80 fs/file_table.c:468 task_work_run+0x1d4/0x260 kernel/task_work.c:227 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0x6b5/0x2300 kernel/exit.c:966 do_group_exit+0x21c/0x2d0 kernel/exit.c:1107 get_signal+0x125d/0x1310 kernel/signal.c:3034 arch_do_signal_or_restart+0xa0/0x790 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop+0x72/0x130 kernel/entry/common.c:40 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline] do_syscall_64+0x2bd/0xfa0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff8880580e4800 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 48 bytes inside of freed 512-byte region [ffff8880580e4800, ffff8880580e4a00) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff8880580e5000 pfn:0x580e4 head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0x80000000000240(workingset|head|node=0|zone=1) page_type: f5(slab) raw: 0080000000000240 ffff88813ff26c80 ffffea0000cc4310 ffffea0001679d10 raw: ffff8880580e5000 000000000010000c 00000000f5000000 0000000000000000 head: 0080000000000240 ffff88813ff26c80 ffffea0000cc4310 ffffea0001679d10 head: ffff8880580e5000 000000000010000c 00000000f5000000 0000000000000000 head: 0080000000000002 ffffea0001603901 00000000ffffffff 00000000ffffffff head: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000004 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5801, tgid 5801 (syz-executor), ts 77459050505, free_ts 77458826756 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1850 prep_new_page mm/page_alloc.c:1858 [inline] get_page_from_freelist+0x28c0/0x2960 mm/page_alloc.c:3884 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5183 alloc_pages_mpol+0xd1/0x380 mm/mempolicy.c:2416 alloc_slab_page mm/slub.c:3031 [inline] allocate_slab+0x96/0x3a0 mm/slub.c:3204 new_slab mm/slub.c:3258 [inline] ___slab_alloc+0xb12/0x13f0 mm/slub.c:4628 __slab_alloc+0xc6/0x1f0 mm/slub.c:4747 __slab_alloc_node mm/slub.c:4823 [inline] slab_alloc_node mm/slub.c:5234 [inline] __kmalloc_cache_noprof+0xec/0x6c0 mm/slub.c:5720 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+0xea1/0x13c0 net/ipv6/addrconf.c:475 addrconf_notify+0x794/0x1010 net/ipv6/addrconf.c:3650 notifier_call_chain+0x1b3/0x3e0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2267 [inline] call_netdevice_notifiers net/core/dev.c:2281 [inline] register_netdevice+0x163c/0x1b10 net/core/dev.c:11332 ip6gre_newlink_common+0x3dd/0x590 net/ipv6/ip6_gre.c:1956 ip6gre_newlink+0x228/0x360 net/ipv6/ip6_gre.c:1989 rtnl_newlink_create+0x30d/0xb00 net/core/rtnetlink.c:3833 page last free pid 5801 tgid 5801 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1394 [inline] __free_frozen_pages+0xfb6/0x1140 mm/page_alloc.c:2906 stack_depot_save_flags+0x436/0x860 lib/stackdepot.c:727 kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x4f/0x80 mm/kasan/common.c:77 poison_kmalloc_redzone mm/kasan/common.c:400 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:417 kasan_kmalloc include/linux/kasan.h:262 [inline] __do_kmalloc_node mm/slub.c:5604 [inline] __kmalloc_noprof+0x233/0x7d0 mm/slub.c:5616 kmalloc_noprof include/linux/slab.h:961 [inline] kzalloc_noprof include/linux/slab.h:1094 [inline] __register_sysctl_table+0x72/0x1340 fs/proc/proc_sysctl.c:1379 __addrconf_sysctl_register+0x328/0x4c0 net/ipv6/addrconf.c:7323 addrconf_sysctl_register+0x168/0x1c0 net/ipv6/addrconf.c:7371 ipv6_add_dev+0xd84/0x13c0 net/ipv6/addrconf.c:460 addrconf_notify+0x794/0x1010 net/ipv6/addrconf.c:3650 notifier_call_chain+0x1b3/0x3e0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2267 [inline] call_netdevice_notifiers net/core/dev.c:2281 [inline] register_netdevice+0x163c/0x1b10 net/core/dev.c:11332 ip6gre_newlink_common+0x3dd/0x590 net/ipv6/ip6_gre.c:1956 ip6gre_newlink+0x228/0x360 net/ipv6/ip6_gre.c:1989 rtnl_newlink_create+0x30d/0xb00 net/core/rtnetlink.c:3833 __rtnl_newlink net/core/rtnetlink.c:3950 [inline] rtnl_newlink+0x16e4/0x1c80 net/core/rtnetlink.c:4065 Memory state around the buggy address: ffff8880580e4700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880580e4780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8880580e4800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880580e4880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880580e4900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================