================================================================== BUG: KASAN: use-after-free in kobject_get+0x113/0x120 lib/kobject.c:663 Read of size 1 at addr ffff88810b1ab83c by task syz.5.2094/7708 CPU: 1 PID: 7708 Comm: syz.5.2094 Tainted: G W syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Call Trace: __dump_stack+0x21/0x24 lib/dump_stack.c:77 dump_stack_lvl+0x1a7/0x208 lib/dump_stack.c:118 print_address_description+0x7f/0x2c0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:435 [inline] kasan_report+0x100/0x140 mm/kasan/report.c:452 __asan_report_load1_noabort+0x14/0x20 mm/kasan/report_generic.c:306 kobject_get+0x113/0x120 lib/kobject.c:663 get_device drivers/base/core.c:3361 [inline] device_add+0x331/0xc00 drivers/base/core.c:3191 device_create_groups_vargs drivers/base/core.c:3960 [inline] device_create+0x26c/0x300 drivers/base/core.c:4002 create_function_device+0x60/0x70 drivers/usb/gadget/configfs.c:31 create_alsa_device drivers/usb/gadget/function/f_midi.c:1262 [inline] f_midi_alloc_inst+0x1a8/0x380 drivers/usb/gadget/function/f_midi.c:1303 try_get_usb_function_instance drivers/usb/gadget/functions.c:28 [inline] usb_get_function_instance+0xe2/0x2f0 drivers/usb/gadget/functions.c:44 function_make+0x118/0x350 drivers/usb/gadget/configfs.c:636 configfs_mkdir+0x5d2/0xd90 fs/configfs/dir.c:1354 vfs_mkdir+0x42c/0x600 fs/namei.c:3798 do_mkdirat+0x14c/0x340 fs/namei.c:3820 __do_sys_mkdirat fs/namei.c:3831 [inline] __se_sys_mkdirat fs/namei.c:3829 [inline] __x64_sys_mkdirat+0x7b/0x90 fs/namei.c:3829 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x61/0xcb RIP: 0033:0x7f60fe1d6019 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f60fcc2f028 EFLAGS: 00000246 ORIG_RAX: 0000000000000102 RAX: ffffffffffffffda RBX: 00007f60fe45dfa0 RCX: 00007f60fe1d6019 RDX: 00000000000001ff RSI: 0000200000000100 RDI: ffffffffffffff9c RBP: 00007f60fe26d00c R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f60fe45e038 R14: 00007f60fe45dfa0 R15: 00007fffb42cee28 Allocated by task 6728: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:45 [inline] set_alloc_info mm/kasan/common.c:430 [inline] ____kasan_kmalloc mm/kasan/common.c:509 [inline] __kasan_kmalloc+0xd4/0x100 mm/kasan/common.c:518 kasan_kmalloc include/linux/kasan.h:254 [inline] __kmalloc+0x19f/0x330 mm/slub.c:4038 kmalloc include/linux/slab.h:560 [inline] kzalloc include/linux/slab.h:667 [inline] __register_sysctl_table+0xeb/0x1240 fs/proc/proc_sysctl.c:1323 register_net_sysctl+0x2c/0x40 net/sysctl_net.c:121 neigh_sysctl_register+0x9a9/0xa90 net/core/neighbour.c:3713 devinet_sysctl_register+0xaf/0x1e0 net/ipv4/devinet.c:2635 inetdev_init+0x26c/0x490 net/ipv4/devinet.c:277 inetdev_event+0x1f4/0x1010 net/ipv4/devinet.c:1544 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0x90/0x100 kernel/notifier.c:410 call_netdevice_notifiers_info net/core/dev.c:2052 [inline] call_netdevice_notifiers_extack net/core/dev.c:2064 [inline] call_netdevice_notifiers+0x119/0x190 net/core/dev.c:2078 register_netdevice+0x100a/0x13a0 net/core/dev.c:10098 wg_newlink+0x4f1/0x7a0 drivers/net/wireguard/device.c:355 __rtnl_newlink net/core/rtnetlink.c:3486 [inline] rtnl_newlink+0x1307/0x1830 net/core/rtnetlink.c:3534 rtnetlink_rcv_msg+0x9e9/0xca0 net/core/rtnetlink.c:5614 netlink_rcv_skb+0x1e9/0x430 net/netlink/af_netlink.c:2508 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:5632 netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline] netlink_unicast+0x86c/0xa30 net/netlink/af_netlink.c:1340 netlink_sendmsg+0x949/0xb70 net/netlink/af_netlink.c:1919 sock_sendmsg_nosec net/socket.c:652 [inline] __sock_sendmsg net/socket.c:664 [inline] __sys_sendto+0x467/0x620 net/socket.c:2007 __do_sys_sendto net/socket.c:2019 [inline] __se_sys_sendto net/socket.c:2015 [inline] __x64_sys_sendto+0xe5/0x100 net/socket.c:2015 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x61/0xcb Freed by task 5: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4a/0x70 mm/kasan/common.c:45 kasan_set_free_info+0x23/0x40 mm/kasan/generic.c:370 ____kasan_slab_free+0x125/0x160 mm/kasan/common.c:362 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:370 kasan_slab_free include/linux/kasan.h:220 [inline] slab_free_hook mm/slub.c:1600 [inline] slab_free_freelist_hook+0xc5/0x190 mm/slub.c:1626 slab_free mm/slub.c:3208 [inline] kmem_cache_free_bulk+0x4b3/0x6d0 mm/slub.c:3341 kfree_bulk include/linux/slab.h:412 [inline] kfree_rcu_work+0x16f/0x890 kernel/rcu/tree.c:3242 process_one_work+0x6fd/0xbc0 kernel/workqueue.c:2301 worker_thread+0xa8e/0x13c0 kernel/workqueue.c:2447 kthread+0x324/0x3b0 kernel/kthread.c:313 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 Last potentially related work creation: kasan_save_stack+0x3a/0x60 mm/kasan/common.c:38 __kasan_record_aux_stack+0xd2/0x100 mm/kasan/generic.c:348 kasan_record_aux_stack_noalloc+0xb/0x10 mm/kasan/generic.c:358 kvfree_call_rcu+0x117/0x670 kernel/rcu/tree.c:3539 drop_sysctl_table+0x2f5/0x430 fs/proc/proc_sysctl.c:1684 unregister_sysctl_table+0x75/0x120 fs/proc/proc_sysctl.c:1722 unregister_net_sysctl_table+0x15/0x20 net/sysctl_net.c:127 neigh_sysctl_unregister+0x78/0x90 net/core/neighbour.c:3732 devinet_sysctl_unregister net/ipv4/devinet.c:2650 [inline] inetdev_destroy net/ipv4/devinet.c:326 [inline] inetdev_event+0x7df/0x1010 net/ipv4/devinet.c:1612 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0x90/0x100 kernel/notifier.c:410 call_netdevice_notifiers_info net/core/dev.c:2052 [inline] call_netdevice_notifiers_extack net/core/dev.c:2064 [inline] call_netdevice_notifiers net/core/dev.c:2078 [inline] unregister_netdevice_many+0x100e/0x19f0 net/core/dev.c:10778 default_device_exit_batch+0x35e/0x3c0 net/core/dev.c:11298 ops_exit_list net/core/net_namespace.c:190 [inline] cleanup_net+0x5fe/0xb80 net/core/net_namespace.c:609 process_one_work+0x6fd/0xbc0 kernel/workqueue.c:2301 worker_thread+0xa8e/0x13c0 kernel/workqueue.c:2447 kthread+0x324/0x3b0 kernel/kthread.c:313 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 The buggy address belongs to the object at ffff88810b1ab800 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 60 bytes inside of 1024-byte region [ffff88810b1ab800, ffff88810b1abc00) The buggy address belongs to the page: page:ffffea00042c6a00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x10b1a8 head:ffffea00042c6a00 order:3 compound_mapcount:0 compound_pincount:0 flags: 0x4000000000010200(slab|head) raw: 4000000000010200 dead000000000100 dead000000000122 ffff888100042f00 raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1, ts 2791699904, free_ts 0 set_page_owner include/linux/page_owner.h:35 [inline] post_alloc_hook mm/page_alloc.c:2456 [inline] prep_new_page+0x176/0x190 mm/page_alloc.c:2462 get_page_from_freelist+0x225f/0x23f0 mm/page_alloc.c:4254 __alloc_pages_nodemask+0x29a/0x640 mm/page_alloc.c:5384 alloc_slab_page mm/slub.c:-1 [inline] allocate_slab mm/slub.c:1813 [inline] new_slab+0x84/0x3f0 mm/slub.c:1874 new_slab_objects mm/slub.c:2632 [inline] ___slab_alloc+0x2f8/0x4c0 mm/slub.c:2796 __slab_alloc+0x63/0xa0 mm/slub.c:2836 slab_alloc_node mm/slub.c:2918 [inline] slab_alloc mm/slub.c:2960 [inline] __kmalloc+0x1f9/0x330 mm/slub.c:4034 kmalloc_array include/linux/slab.h:595 [inline] blk_stat_alloc_callback+0x91/0x210 block/blk-stat.c:113 blk_mq_init_allocated_queue+0x8e/0x1850 block/blk-mq.c:3346 blk_mq_init_queue_data block/blk-mq.c:3180 [inline] blk_mq_init_queue+0x6e/0xd0 block/blk-mq.c:3190 scsi_mq_alloc_queue+0x42/0x140 drivers/scsi/scsi_lib.c:1911 scsi_alloc_sdev+0x611/0x920 drivers/scsi/scsi_scan.c:284 scsi_probe_and_add_lun+0x17d/0x3370 drivers/scsi/scsi_scan.c:1098 __scsi_scan_target+0x1d2/0xbf0 drivers/scsi/scsi_scan.c:1581 scsi_scan_channel drivers/scsi/scsi_scan.c:1669 [inline] scsi_scan_host_selected+0x34e/0x600 drivers/scsi/scsi_scan.c:1698 do_scsi_scan_host drivers/scsi/scsi_scan.c:1837 [inline] scsi_scan_host+0x39e/0x670 drivers/scsi/scsi_scan.c:1867 page_owner free stack trace missing Memory state around the buggy address: ffff88810b1ab700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88810b1ab780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88810b1ab800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88810b1ab880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88810b1ab900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== general protection fault, probably for non-canonical address 0xdffffc0000000004: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000020-0x0000000000000027] CPU: 0 PID: 7708 Comm: syz.5.2094 Tainted: G B W syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 RIP: 0010:idr_alloc_cyclic+0x4e/0x1a0 lib/idr.c:121 Code: 04 25 28 00 00 00 48 89 45 d0 49 be 00 00 00 00 00 fc ff df e8 43 08 0b ff 49 8d 4c 24 14 48 89 4d c0 48 c1 e9 03 48 89 4d a8 <42> 0f b6 04 31 84 c0 0f 85 f8 00 00 00 45 8b 7c 24 14 31 ff 89 de RSP: 0018:ffffc90000f874d8 EFLAGS: 00010203 RAX: ffffffff82599b3d RBX: 0000000000000000 RCX: 0000000000000004 RDX: ffffc900060fc000 RSI: 000000000007ffff RDI: 0000000000080000 RBP: ffffc90000f87530 R08: 0000000000000a20 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff520001f0e98 R12: 0000000000000010 R13: 0000000000000001 R14: dffffc0000000000 R15: 1ffff920001f0eb0 FS: 00007f60fcc2f6c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f32a3d28ff8 CR3: 000000011a56e000 CR4: 00000000003506b0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __kernfs_new_node+0x130/0x670 fs/kernfs/dir.c:669 kernfs_new_node+0x150/0x260 fs/kernfs/dir.c:739 kernfs_create_dir_ns+0x47/0x130 fs/kernfs/dir.c:1087 sysfs_create_dir_ns+0x128/0x290 fs/sysfs/dir.c:59 create_dir lib/kobject.c:89 [inline] kobject_add_internal+0x774/0xde0 lib/kobject.c:263 kobject_add_varg lib/kobject.c:398 [inline] kobject_add+0x165/0x230 lib/kobject.c:450 class_dir_create_and_add drivers/base/core.c:2825 [inline] get_device_parent+0x3a6/0x410 drivers/base/core.c:2880 device_add+0x349/0xc00 drivers/base/core.c:3192 device_create_groups_vargs drivers/base/core.c:3960 [inline] device_create+0x26c/0x300 drivers/base/core.c:4002 create_function_device+0x60/0x70 drivers/usb/gadget/configfs.c:31 create_alsa_device drivers/usb/gadget/function/f_midi.c:1262 [inline] f_midi_alloc_inst+0x1a8/0x380 drivers/usb/gadget/function/f_midi.c:1303 try_get_usb_function_instance drivers/usb/gadget/functions.c:28 [inline] usb_get_function_instance+0xe2/0x2f0 drivers/usb/gadget/functions.c:44 function_make+0x118/0x350 drivers/usb/gadget/configfs.c:636 configfs_mkdir+0x5d2/0xd90 fs/configfs/dir.c:1354 vfs_mkdir+0x42c/0x600 fs/namei.c:3798 do_mkdirat+0x14c/0x340 fs/namei.c:3820 __do_sys_mkdirat fs/namei.c:3831 [inline] __se_sys_mkdirat fs/namei.c:3829 [inline] __x64_sys_mkdirat+0x7b/0x90 fs/namei.c:3829 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x61/0xcb RIP: 0033:0x7f60fe1d6019 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f60fcc2f028 EFLAGS: 00000246 ORIG_RAX: 0000000000000102 RAX: ffffffffffffffda RBX: 00007f60fe45dfa0 RCX: 00007f60fe1d6019 RDX: 00000000000001ff RSI: 0000200000000100 RDI: ffffffffffffff9c RBP: 00007f60fe26d00c R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f60fe45e038 R14: 00007f60fe45dfa0 R15: 00007fffb42cee28 Modules linked in: ---[ end trace ca2efa3beb8b58f2 ]--- RIP: 0010:idr_alloc_cyclic+0x4e/0x1a0 lib/idr.c:121 Code: 04 25 28 00 00 00 48 89 45 d0 49 be 00 00 00 00 00 fc ff df e8 43 08 0b ff 49 8d 4c 24 14 48 89 4d c0 48 c1 e9 03 48 89 4d a8 <42> 0f b6 04 31 84 c0 0f 85 f8 00 00 00 45 8b 7c 24 14 31 ff 89 de RSP: 0018:ffffc90000f874d8 EFLAGS: 00010203 RAX: ffffffff82599b3d RBX: 0000000000000000 RCX: 0000000000000004 RDX: ffffc900060fc000 RSI: 000000000007ffff RDI: 0000000000080000 RBP: ffffc90000f87530 R08: 0000000000000a20 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff520001f0e98 R12: 0000000000000010 R13: 0000000000000001 R14: dffffc0000000000 R15: 1ffff920001f0eb0 FS: 00007f60fcc2f6c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f32a3d28ff8 CR3: 000000011a56e000 CR4: 00000000003506b0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 04 25 add $0x25,%al 2: 28 00 sub %al,(%rax) 4: 00 00 add %al,(%rax) 6: 48 89 45 d0 mov %rax,-0x30(%rbp) a: 49 be 00 00 00 00 00 movabs $0xdffffc0000000000,%r14 11: fc ff df 14: e8 43 08 0b ff call 0xff0b085c 19: 49 8d 4c 24 14 lea 0x14(%r12),%rcx 1e: 48 89 4d c0 mov %rcx,-0x40(%rbp) 22: 48 c1 e9 03 shr $0x3,%rcx 26: 48 89 4d a8 mov %rcx,-0x58(%rbp) * 2a: 42 0f b6 04 31 movzbl (%rcx,%r14,1),%eax <-- trapping instruction 2f: 84 c0 test %al,%al 31: 0f 85 f8 00 00 00 jne 0x12f 37: 45 8b 7c 24 14 mov 0x14(%r12),%r15d 3c: 31 ff xor %edi,%edi 3e: 89 de mov %ebx,%esi