KASAN: slab-use-after-free Read in netdev_register

ID	Workflow	Result	Correct	Bug	Created	Started	Finished	Revision	Error
2502f3e1	moderation	Actionable: ✅	❓	KASAN: slab-use-after-free Read in netdev_register_kobject (2)	2026/06/01 14:10	2026/06/01 14:10	2026/06/01 15:07	386cc6da
c54ba430	assessment-security	DenialOfService: ✅ Exploitable: ✅ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ✅ RemoteTrigger: ✅ Unprivileged: ❌ UserNamespace: ❌ VMGuestTrigger: ❌ VMHostTrigger: ❌	❓	KASAN: slab-use-after-free Read in netdev_register_kobject (2)	2026/06/01 14:09	2026/06/01 14:09	2026/06/01 15:02	386cc6da

Title	Replies (including bot)	Last reply
[PATCH] Bluetooth: bnep: pin L2CAP connection during netdev registration	2 (2)	2026/06/30 20:32
[syzbot] [kernel?] KASAN: slab-use-after-free Read in netdev_register_kobject (2)	0 (1)	2026/06/01 15:08

Title

Replies (including bot)

Last reply

[PATCH] Bluetooth: bnep: pin L2CAP connection during netdev registration

2 (2)

2026/06/30 20:32

[syzbot] [kernel?] KASAN: slab-use-after-free Read in netdev_register_kobject (2)

0 (1)

2026/06/01 15:08

Kernel	Title	Rank 🛈	Repro	Cause bisect	Count	Last	Reported	Patched	Status
upstream	KASAN: slab-use-after-free Read in netdev_register_kobject kernel	19			1	420d	420d	0/29	closed as invalid on 2025/07/02 15:51
upstream	general protection fault in netdev_register_kobject kernel	8	C	done	512	1024d	1059d	0/29	closed as dup on 2023/08/31 14:15
linux-4.19	general protection fault in netdev_register_kobject	2			1	1673d	1673d	0/1	auto-closed as invalid on 2022/04/23 17:30

Rank 🛈

upstream

KASAN: slab-use-after-free Read in netdev_register_kobject kernel

420d

0/29

closed as invalid on 2025/07/02 15:51

upstream

general protection fault in netdev_register_kobject kernel

done

512

1024d

1059d

0/29

closed as dup on 2023/08/31 14:15

linux-4.19

general protection fault in netdev_register_kobject

1673d

0/1

auto-closed as invalid on 2022/04/23 17:30

================================================================== BUG: KASAN: slab-use-after-free in kobject_get+0x136/0x150 lib/kobject.c:639 Read of size 1 at addr ffff88806195cd1c by task syz.0.1153/10834 CPU: 2 UID: 0 PID: 10834 Comm: syz.0.1153 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 Call Trace: <TASK> __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0x13d/0x4b0 mm/kasan/report.c:482 kasan_report+0xdf/0x1d0 mm/kasan/report.c:595 kobject_get+0x136/0x150 lib/kobject.c:639 get_device drivers/base/core.c:3802 [inline] device_add+0x19f/0x1950 drivers/base/core.c:3614 netdev_register_kobject+0x1a9/0x3d0 net/core/net-sysfs.c:2343 register_netdevice+0x151c/0x24b0 net/core/dev.c:11423 register_netdev+0x34/0x50 net/core/dev.c:11539 bnep_add_connection+0x723/0xd30 net/bluetooth/bnep/core.c:646 do_bnep_sock_ioctl.isra.0+0x3ac/0x5b0 net/bluetooth/bnep/sock.c:83 sock_do_ioctl+0x118/0x280 net/socket.c:1313 sock_ioctl+0x599/0x6b0 net/socket.c:1434 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl fs/ioctl.c:583 [inline] __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f1812d9ce59 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:00007f1813bc8028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f1813015fa0 RCX: 00007f1812d9ce59 RDX: 00002000000000c0 RSI: 00000000400442c8 RDI: 0000000000000005 RBP: 00007f1812e32d6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f1813016038 R14: 00007f1813015fa0 R15: 00007fff0c06a388 </TASK> Allocated by task 5750: kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415 kmalloc_noprof include/linux/slab.h:950 [inline] kzalloc_noprof include/linux/slab.h:1188 [inline] __hci_conn_add+0x1f4/0x1da0 net/bluetooth/hci_conn.c:1032 hci_conn_add_unset+0x76/0x120 net/bluetooth/hci_conn.c:1159 hci_conn_request_evt+0xa58/0xbb0 net/bluetooth/hci_event.c:3333 hci_event_func net/bluetooth/hci_event.c:7796 [inline] hci_event_packet+0x8e9/0xcd0 net/bluetooth/hci_event.c:7847 hci_rx_work+0x451/0xfc0 net/bluetooth/hci_core.c:4040 process_one_work+0xa0e/0x1980 kernel/workqueue.c:3314 process_scheduled_works kernel/workqueue.c:3397 [inline] worker_thread+0x5ef/0xe50 kernel/workqueue.c:3478 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Freed by task 10685: kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2689 [inline] slab_free mm/slub.c:6251 [inline] kfree+0x223/0x6c0 mm/slub.c:6566 device_release+0xd2/0x270 drivers/base/core.c:2566 kobject_cleanup lib/kobject.c:689 [inline] kobject_release lib/kobject.c:720 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x1f7/0x640 lib/kobject.c:737 put_device drivers/base/core.c:3814 [inline] device_unregister+0x2f/0xe0 drivers/base/core.c:3937 hci_conn_del_sysfs+0xb9/0x1a0 net/bluetooth/hci_sysfs.c:79 hci_conn_cleanup net/bluetooth/hci_conn.c:173 [inline] hci_conn_del+0x506/0x1180 net/bluetooth/hci_conn.c:1309 hci_conn_hash_flush+0x186/0x280 net/bluetooth/hci_conn.c:2737 hci_dev_close_sync+0x5cf/0x13c0 net/bluetooth/hci_sync.c:5383 hci_dev_do_close+0x2e/0xb0 net/bluetooth/hci_core.c:502 hci_unregister_dev+0x227/0x670 net/bluetooth/hci_core.c:2679 vhci_release+0x17d/0x230 drivers/bluetooth/hci_vhci.c:690 __fput+0x3ff/0xb50 fs/file_table.c:510 task_work_run+0x150/0x240 kernel/task_work.c:233 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0x951/0x2af0 kernel/exit.c:976 do_group_exit+0xd5/0x2a0 kernel/exit.c:1119 __do_sys_exit_group kernel/exit.c:1130 [inline] __se_sys_exit_group kernel/exit.c:1128 [inline] __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1128 x64_sys_call+0x102c/0x1530 arch/x86/include/generated/asm/syscalls_64.h:232 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Last potentially related work creation: kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_record_aux_stack+0xa7/0xc0 mm/kasan/generic.c:556 insert_work+0x36/0x230 kernel/workqueue.c:2226 __queue_work+0x9a2/0x1270 kernel/workqueue.c:2393 __queue_delayed_work+0x357/0x450 kernel/workqueue.c:2560 queue_delayed_work_on+0x180/0x1e0 kernel/workqueue.c:2612 queue_delayed_work include/linux/workqueue.h:713 [inline] hci_conn_drop include/net/bluetooth/hci_core.h:1712 [inline] hci_conn_drop include/net/bluetooth/hci_core.h:1686 [inline] l2cap_chan_del+0x649/0x930 net/bluetooth/l2cap_core.c:674 l2cap_conn_del+0x395/0x710 net/bluetooth/l2cap_core.c:1804 l2cap_disconn_cfm net/bluetooth/l2cap_core.c:7511 [inline] l2cap_disconn_cfm+0x9f/0x100 net/bluetooth/l2cap_core.c:7504 hci_disconn_cfm include/net/bluetooth/hci_core.h:2154 [inline] hci_conn_hash_flush+0x10e/0x280 net/bluetooth/hci_conn.c:2736 hci_dev_close_sync+0x5cf/0x13c0 net/bluetooth/hci_sync.c:5383 hci_dev_do_close+0x2e/0xb0 net/bluetooth/hci_core.c:502 hci_unregister_dev+0x227/0x670 net/bluetooth/hci_core.c:2679 vhci_release+0x17d/0x230 drivers/bluetooth/hci_vhci.c:690 __fput+0x3ff/0xb50 fs/file_table.c:510 task_work_run+0x150/0x240 kernel/task_work.c:233 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0x951/0x2af0 kernel/exit.c:976 do_group_exit+0xd5/0x2a0 kernel/exit.c:1119 __do_sys_exit_group kernel/exit.c:1130 [inline] __se_sys_exit_group kernel/exit.c:1128 [inline] __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1128 x64_sys_call+0x102c/0x1530 arch/x86/include/generated/asm/syscalls_64.h:232 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88806195c000 which belongs to the cache kmalloc-8k of size 8192 The buggy address is located 3356 bytes inside of freed 8192-byte region [ffff88806195c000, ffff88806195e000) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x61958 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88801b843180 dead000000000100 dead000000000122 raw: 0000000000000000 0000000800020002 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88801b843180 dead000000000100 dead000000000122 head: 0000000000000000 0000000800020002 00000000f5000000 0000000000000000 head: 00fff00000000003 fffffffffffffe01 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008 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 7332, tgid 7332 (syz-executor), ts 89209836633, free_ts 89188109028 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1853 prep_new_page mm/page_alloc.c:1861 [inline] get_page_from_freelist+0x11a6/0x3410 mm/page_alloc.c:3941 __alloc_frozen_pages_noprof+0x27c/0x2bc0 mm/page_alloc.c:5221 alloc_slab_page mm/slub.c:3278 [inline] allocate_slab mm/slub.c:3467 [inline] new_slab+0xa6/0x6c0 mm/slub.c:3525 refill_objects+0x277/0x420 mm/slub.c:7272 refill_sheaf mm/slub.c:2816 [inline] __pcs_replace_empty_main+0x375/0x650 mm/slub.c:4652 alloc_from_pcs mm/slub.c:4750 [inline] slab_alloc_node mm/slub.c:4884 [inline] __kmalloc_cache_noprof+0x493/0x6f0 mm/slub.c:5415 kmalloc_noprof include/linux/slab.h:950 [inline] kzalloc_noprof include/linux/slab.h:1188 [inline] macvlan_port_create drivers/net/macvlan.c:1260 [inline] macvlan_common_newlink+0x476/0x18b0 drivers/net/macvlan.c:1498 rtnl_newlink_create net/core/rtnetlink.c:3864 [inline] __rtnl_newlink net/core/rtnetlink.c:3995 [inline] rtnl_newlink+0x1499/0x2380 net/core/rtnetlink.c:4110 rtnetlink_rcv_msg+0x95e/0xe90 net/core/rtnetlink.c:6997 netlink_rcv_skb+0x159/0x420 net/netlink/af_netlink.c:2555 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x585/0x850 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x8b0/0xda0 net/netlink/af_netlink.c:1899 sock_sendmsg_nosec net/socket.c:787 [inline] __sock_sendmsg net/socket.c:802 [inline] __sys_sendto+0x468/0x4b0 net/socket.c:2265 __do_sys_sendto net/socket.c:2272 [inline] __se_sys_sendto net/socket.c:2268 [inline] __x64_sys_sendto+0xe0/0x1c0 net/socket.c:2268 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 page last free pid 7332 tgid 7332 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1397 [inline] __free_frozen_pages+0x794/0x10a0 mm/page_alloc.c:2938 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x47/0xf0 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x1a0/0x1f0 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:350 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4570 [inline] slab_alloc_node mm/slub.c:4899 [inline] __kmalloc_cache_noprof+0x243/0x6f0 mm/slub.c:5415 kmalloc_noprof include/linux/slab.h:950 [inline] kzalloc_noprof include/linux/slab.h:1188 [inline] garp_init_port net/802/garp.c:550 [inline] garp_init_applicant+0x38d/0x4e0 net/802/garp.c:578 register_vlan_dev+0x197/0x910 net/8021q/vlan.c:167 vlan_newlink+0x48c/0x750 net/8021q/vlan_netlink.c:194 rtnl_newlink_create net/core/rtnetlink.c:3864 [inline] __rtnl_newlink net/core/rtnetlink.c:3995 [inline] rtnl_newlink+0x1499/0x2380 net/core/rtnetlink.c:4110 rtnetlink_rcv_msg+0x95e/0xe90 net/core/rtnetlink.c:6997 netlink_rcv_skb+0x159/0x420 net/netlink/af_netlink.c:2555 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x585/0x850 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x8b0/0xda0 net/netlink/af_netlink.c:1899 sock_sendmsg_nosec net/socket.c:787 [inline] __sock_sendmsg net/socket.c:802 [inline] __sys_sendto+0x468/0x4b0 net/socket.c:2265 __do_sys_sendto net/socket.c:2272 [inline] __se_sys_sendto net/socket.c:2268 [inline] __x64_sys_sendto+0xe0/0x1c0 net/socket.c:2268 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 Memory state around the buggy address: ffff88806195cc00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88806195cc80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88806195cd00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88806195cd80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88806195ce00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================

Crashes (3):
Time	Kernel	Commit	Syzkaller	Config	Log	Report	VM info	Assets (help?)	Manager	Title
2026/06/06 10:26	upstream	c10130c234c8	cc095639	.config	console log	report	info	[disk image (non-bootable)] [vmlinux] [kernel image]	ci-qemu-upstream	KASAN: slab-use-after-free Read in netdev_register_kobject
2026/05/24 04:18	upstream	4cbfe4502e3d	c69befb3	.config	console log	report	info	[disk image (non-bootable)] [vmlinux] [kernel image]	ci-qemu-upstream-386	KASAN: slab-use-after-free Read in netdev_register_kobject
2026/05/15 06:34	git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci	5cbb61bf4168	6ccb967e	.config	console log	report	info	[disk image] [vmlinux] [kernel image]	ci-upstream-gce-arm64	KASAN: slab-use-after-free Read in netdev_register_kobject

Crashes (3):

Assets (help?)