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BUG: KASAN: slab-use-after-free in __mutex_waiter_is_first kernel/locking/mutex.c:172 [inline]
BUG: KASAN: slab-use-after-free in __mutex_lock_common kernel/locking/mutex.c:664 [inline]
BUG: KASAN: slab-use-after-free in __mutex_lock+0x830/0x1010 kernel/locking/mutex.c:730
Read of size 8 at addr ffff888031bfd320 by task kworker/0:9/14047
CPU: 0 UID: 0 PID: 14047 Comm: kworker/0:9 Not tainted 6.14.0-rc6-syzkaller-00022-gb7f94fcf5546 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Workqueue: events l2cap_chan_timeout
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
__mutex_waiter_is_first kernel/locking/mutex.c:172 [inline]
__mutex_lock_common kernel/locking/mutex.c:664 [inline]
__mutex_lock+0x830/0x1010 kernel/locking/mutex.c:730
l2cap_chan_timeout+0x63/0x360 net/bluetooth/l2cap_core.c:417
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
</TASK>
Allocated by task 29514:
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]
l2cap_conn_add+0xa9/0x8e0 net/bluetooth/l2cap_core.c:6825
l2cap_chan_connect+0x61e/0xeb0 net/bluetooth/l2cap_core.c:7016
bt_6lowpan_connect net/bluetooth/6lowpan.c:894 [inline]
lowpan_control_write+0x568/0x850 net/bluetooth/6lowpan.c:1129
full_proxy_write+0x17b/0x250 fs/debugfs/file.c:398
vfs_write+0x29f/0xd10 fs/read_write.c:677
ksys_write+0x18f/0x2b0 fs/read_write.c:731
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
Freed by task 28116:
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
hci_disconn_cfm include/net/bluetooth/hci_core.h:2069 [inline]
hci_conn_hash_flush+0x1be/0x350 net/bluetooth/hci_conn.c:2698
hci_dev_close_sync+0xa8b/0x1260 net/bluetooth/hci_sync.c:5197
hci_dev_do_close net/bluetooth/hci_core.c:482 [inline]
hci_unregister_dev+0x20b/0x510 net/bluetooth/hci_core.c:2677
vhci_release+0x80/0xd0 drivers/bluetooth/hci_vhci.c:664
__fput+0x3e9/0x9f0 fs/file_table.c:464
task_work_run+0x24f/0x310 kernel/task_work.c:227
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0xa2a/0x28e0 kernel/exit.c:938
do_group_exit+0x207/0x2c0 kernel/exit.c:1087
__do_sys_exit_group kernel/exit.c:1098 [inline]
__se_sys_exit_group kernel/exit.c:1096 [inline]
__x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1096
x64_sys_call+0x26a8/0x26b0 arch/x86/include/generated/asm/syscalls_64.h:232
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
The buggy address belongs to the object at ffff888031bfd000
which belongs to the cache kmalloc-1k of size 1024
The buggy address is located 800 bytes inside of
freed 1024-byte region [ffff888031bfd000, ffff888031bfd400)
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888031bfc800 pfn:0x31bf8
head: order:3 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 ffff88801b041dc0 ffffea0000a5cc10 ffffea000088d010
raw: ffff888031bfc800 0000000000100009 00000000f5000000 0000000000000000
head: 00fff00000000240 ffff88801b041dc0 ffffea0000a5cc10 ffffea000088d010
head: ffff888031bfc800 0000000000100009 00000000f5000000 0000000000000000
head: 00fff00000000003 ffffea0000c6fe01 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 0x52820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 1, tgid 1 (swapper/0), ts 23224314142, free_ts 0
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+0x365c/0x37a0 mm/page_alloc.c:3477
__alloc_frozen_pages_noprof+0x292/0x710 mm/page_alloc.c:4740
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]
__kmalloc_cache_noprof+0x27b/0x390 mm/slub.c:4320
kmalloc_noprof include/linux/slab.h:901 [inline]
kzalloc_noprof include/linux/slab.h:1037 [inline]
tipc_link_create+0x101/0xda0 net/tipc/link.c:490
tipc_link_bc_create+0xe9/0x4d0 net/tipc/link.c:564
tipc_bcast_init+0x1b6/0x390 net/tipc/bcast.c:701
tipc_init_net+0x26e/0x330 net/tipc/core.c:84
ops_init+0x349/0x5b0 net/core/net_namespace.c:138
__register_pernet_operations net/core/net_namespace.c:1272 [inline]
register_pernet_operations+0x30d/0x630 net/core/net_namespace.c:1348
register_pernet_device+0x33/0x80 net/core/net_namespace.c:1435
tipc_init+0x56/0x190 net/tipc/core.c:160
page_owner free stack trace missing
Memory state around the buggy address:
ffff888031bfd200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff888031bfd280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888031bfd300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff888031bfd380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff888031bfd400: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
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