syzbot

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BUG: KASAN: slab-use-after-free in cfusbl_device_notify+0x188/0x6e0 net/caif/caif_usb.c:142
Read of size 8 at addr ffff88802a144bf0 by task syz.5.405/7559

CPU: 0 UID: 0 PID: 7559 Comm: syz.5.405 Not tainted 6.14.0-rc5-syzkaller-00214-g21e4543a2e2f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:408 [inline]
 print_report+0x16e/0x5b0 mm/kasan/report.c:521
 kasan_report+0x143/0x180 mm/kasan/report.c:634
 cfusbl_device_notify+0x188/0x6e0 net/caif/caif_usb.c:142
 notifier_call_chain+0x1a5/0x3f0 kernel/notifier.c:85
 call_netdevice_notifiers_extack net/core/dev.c:2244 [inline]
 call_netdevice_notifiers net/core/dev.c:2258 [inline]
 register_netdevice+0x126c/0x1b60 net/core/dev.c:10938
 register_netdev+0x40/0x50 net/core/dev.c:11056
 bnep_add_connection+0x823/0xe10 net/bluetooth/bnep/core.c:624
 do_bnep_sock_ioctl+0x4f8/0x8d0 net/bluetooth/bnep/sock.c:83
 sock_do_ioctl+0x158/0x460 net/socket.c:1199
 sock_ioctl+0x626/0x8e0 net/socket.c:1318
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:906 [inline]
 __se_sys_ioctl+0xf5/0x170 fs/ioctl.c:892
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd09bb8d169
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:00007fd09c9d0038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fd09bda5fa0 RCX: 00007fd09bb8d169
RDX: 00004000000000c0 RSI: 00000000400442c8 RDI: 0000000000000005
RBP: 00007fd09bc0e2a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fd09bda5fa0 R15: 00007ffda00f29b8
 </TASK>

Allocated by task 5833:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
 __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:394
 kasan_kmalloc include/linux/kasan.h:260 [inline]
 __kmalloc_cache_noprof+0x243/0x390 mm/slub.c:4325
 kmalloc_noprof include/linux/slab.h:901 [inline]
 kzalloc_noprof include/linux/slab.h:1037 [inline]
 __hci_conn_add+0x2f9/0x1890 net/bluetooth/hci_conn.c:935
 hci_conn_request_evt+0x642/0xf00 net/bluetooth/hci_event.c:3286
 hci_event_func net/bluetooth/hci_event.c:7473 [inline]
 hci_event_packet+0xac1/0x1540 net/bluetooth/hci_event.c:7525
 hci_rx_work+0x3f3/0xdb0 net/bluetooth/hci_core.c:4015
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xabe/0x18e0 kernel/workqueue.c:3319
 worker_thread+0x870/0xd30 kernel/workqueue.c:3400
 kthread+0x7a9/0x920 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Freed by task 56:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:576
 poison_slab_object mm/kasan/common.c:247 [inline]
 __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2353 [inline]
 slab_free mm/slub.c:4609 [inline]
 kfree+0x196/0x430 mm/slub.c:4757
 device_release+0x99/0x1c0
 kobject_cleanup lib/kobject.c:689 [inline]
 kobject_release lib/kobject.c:720 [inline]
 kref_put include/linux/kref.h:65 [inline]
 kobject_put+0x22f/0x480 lib/kobject.c:737
 hci_conn_cleanup net/bluetooth/hci_conn.c:174 [inline]
 hci_conn_del+0x8c4/0xc40 net/bluetooth/hci_conn.c:1164
 hci_conn_failed+0x319/0x400 net/bluetooth/hci_conn.c:1267
 hci_abort_conn_sync+0xd27/0x1340 net/bluetooth/hci_sync.c:5588
 hci_cmd_sync_work+0x22b/0x400 net/bluetooth/hci_sync.c:332
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xabe/0x18e0 kernel/workqueue.c:3319
 worker_thread+0x870/0xd30 kernel/workqueue.c:3400
 kthread+0x7a9/0x920 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Last potentially related work creation:
 kasan_save_stack+0x3f/0x60 mm/kasan/common.c:47
 kasan_record_aux_stack+0xaa/0xc0 mm/kasan/generic.c:548
 insert_work+0x3e/0x330 kernel/workqueue.c:2183
 __queue_work+0xc62/0x1090 kernel/workqueue.c:2345
 queue_delayed_work_on+0x1ca/0x390 kernel/workqueue.c:2561
 l2cap_chan_del+0x291/0x5d0 net/bluetooth/l2cap_core.c:671
 l2cap_conn_del+0x391/0x690 net/bluetooth/l2cap_core.c:1786
 l2cap_connect_cfm+0xcc/0x1090 net/bluetooth/l2cap_core.c:7200
 hci_connect_cfm include/net/bluetooth/hci_core.h:2051 [inline]
 hci_conn_failed+0x287/0x400 net/bluetooth/hci_conn.c:1266
 hci_abort_conn_sync+0xd27/0x1340 net/bluetooth/hci_sync.c:5588
 hci_cmd_sync_work+0x22b/0x400 net/bluetooth/hci_sync.c:332
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xabe/0x18e0 kernel/workqueue.c:3319
 worker_thread+0x870/0xd30 kernel/workqueue.c:3400
 kthread+0x7a9/0x920 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Second to last potentially related work creation:
 kasan_save_stack+0x3f/0x60 mm/kasan/common.c:47
 kasan_record_aux_stack+0xaa/0xc0 mm/kasan/generic.c:548
 insert_work+0x3e/0x330 kernel/workqueue.c:2183
 __queue_work+0xd9a/0x1090 kernel/workqueue.c:2341
 call_timer_fn+0x187/0x650 kernel/time/timer.c:1789
 expire_timers kernel/time/timer.c:1835 [inline]
 __run_timers kernel/time/timer.c:2414 [inline]
 __run_timer_base+0x695/0x8e0 kernel/time/timer.c:2426
 run_timer_base kernel/time/timer.c:2435 [inline]
 run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2445
 handle_softirqs+0x2d4/0x9b0 kernel/softirq.c:561
 __do_softirq kernel/softirq.c:595 [inline]
 invoke_softirq kernel/softirq.c:435 [inline]
 __irq_exit_rcu+0xf7/0x220 kernel/softirq.c:662
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:678
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
 sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1049
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702

The buggy address belongs to the object at ffff88802a144000
 which belongs to the cache kmalloc-8k of size 8192
The buggy address is located 3056 bytes inside of
 freed 8192-byte region [ffff88802a144000, ffff88802a146000)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2a140
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 ffff88801b042280 dead000000000100 dead000000000122
raw: 0000000000000000 0000000000020002 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff88801b042280 dead000000000100 dead000000000122
head: 0000000000000000 0000000000020002 00000000f5000000 0000000000000000
head: 00fff00000000003 ffffea0000a85001 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 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 0xd28c0(GFP_NOWAIT|__GFP_IO|__GFP_FS|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5492, tgid 5492 (dhcpcd), ts 52951754975, free_ts 52926841730
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f4/0x240 mm/page_alloc.c:1551
 prep_new_page mm/page_alloc.c:1559 [inline]
 get_page_from_freelist+0x3651/0x37a0 mm/page_alloc.c:3477
 __alloc_frozen_pages_noprof+0x292/0x710 mm/page_alloc.c:4739
 alloc_pages_mpol+0x311/0x660 mm/mempolicy.c:2270
 alloc_slab_page mm/slub.c:2423 [inline]
 allocate_slab+0x8f/0x3a0 mm/slub.c:2587
 new_slab mm/slub.c:2640 [inline]
 ___slab_alloc+0xc27/0x14a0 mm/slub.c:3826
 __slab_alloc+0x58/0xa0 mm/slub.c:3916
 __slab_alloc_node mm/slub.c:3991 [inline]
 slab_alloc_node mm/slub.c:4152 [inline]
 __do_kmalloc_node mm/slub.c:4293 [inline]
 __kmalloc_node_track_caller_noprof+0x2e9/0x4c0 mm/slub.c:4313
 kmalloc_reserve+0x111/0x2a0 net/core/skbuff.c:537
 __alloc_skb+0x1f3/0x440 net/core/skbuff.c:606
 alloc_skb include/linux/skbuff.h:1331 [inline]
 netlink_dump+0x1ee/0xe10 net/netlink/af_netlink.c:2274
 netlink_recvmsg+0x6ec/0x11a0 net/netlink/af_netlink.c:1964
 sock_recvmsg_nosec net/socket.c:1023 [inline]
 sock_recvmsg+0x22f/0x280 net/socket.c:1045
 ____sys_recvmsg+0x1c6/0x480 net/socket.c:2793
 ___sys_recvmsg net/socket.c:2835 [inline]
 __sys_recvmsg+0x291/0x390 net/socket.c:2868
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
page last free pid 5491 tgid 5491 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1127 [inline]
 free_frozen_pages+0xe04/0x10e0 mm/page_alloc.c:2660
 discard_slab mm/slub.c:2684 [inline]
 __put_partials+0x160/0x1c0 mm/slub.c:3153
 put_cpu_partial+0x17c/0x250 mm/slub.c:3228
 __slab_free+0x290/0x380 mm/slub.c:4479
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4115 [inline]
 slab_alloc_node mm/slub.c:4164 [inline]
 kmem_cache_alloc_node_noprof+0x1d9/0x380 mm/slub.c:4216
 __alloc_skb+0x1c3/0x440 net/core/skbuff.c:596
 alloc_skb include/linux/skbuff.h:1331 [inline]
 alloc_skb_with_frags+0xc3/0x820 net/core/skbuff.c:6522
 sock_alloc_send_pskb+0x91a/0xa60 net/core/sock.c:2914
 unix_dgram_sendmsg+0x5e8/0x1df0 net/unix/af_unix.c:2017
 sock_sendmsg_nosec net/socket.c:718 [inline]
 __sock_sendmsg+0x221/0x270 net/socket.c:733
 sock_write_iter+0x2d7/0x3f0 net/socket.c:1137
 do_iter_readv_writev+0x71a/0x9d0
 vfs_writev+0x38b/0xbc0 fs/read_write.c:1050

Memory state around the buggy address:
 ffff88802a144a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88802a144b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88802a144b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                             ^
 ffff88802a144c00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88802a144c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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