================================================================== BUG: KASAN: slab-use-after-free in force_devcd_write+0x317/0x330 drivers/bluetooth/hci_vhci.c:327 Read of size 8 at addr ffff88807c6c3800 by task syz.8.7763/3663 CPU: 0 UID: 0 PID: 3663 Comm: syz.8.7763 Not tainted 6.14.0-rc7-syzkaller-00137-g5fc319360819 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:408 [inline] print_report+0xc3/0x670 mm/kasan/report.c:521 kasan_report+0xd9/0x110 mm/kasan/report.c:634 force_devcd_write+0x317/0x330 drivers/bluetooth/hci_vhci.c:327 full_proxy_write+0x13c/0x200 fs/debugfs/file.c:398 vfs_write+0x24c/0x1150 fs/read_write.c:677 ksys_write+0x12b/0x250 fs/read_write.c:731 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f7881b8d169 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:00007f7882904038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f7881da5fa0 RCX: 00007f7881b8d169 RDX: 000000000000000e RSI: 0000000000000000 RDI: 0000000000000006 RBP: 00007f7881c0e2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f7881da5fa0 R15: 00007ffed5bbb6c8 Allocated by task 3392: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394 kmalloc_noprof include/linux/slab.h:901 [inline] kzalloc_noprof include/linux/slab.h:1037 [inline] afs_alloc_call+0x51/0x640 fs/afs/rxrpc.c:144 afs_charge_preallocation+0xff/0x330 fs/afs/rxrpc.c:728 afs_open_socket+0x2b3/0x380 fs/afs/rxrpc.c:95 afs_net_init+0x95d/0xc60 fs/afs/main.c:123 ops_init+0x1df/0x5f0 net/core/net_namespace.c:138 setup_net+0x21f/0x860 net/core/net_namespace.c:362 copy_net_ns+0x2a6/0x5f0 net/core/net_namespace.c:516 create_new_namespaces+0x3ea/0xad0 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0xc0/0x1f0 kernel/nsproxy.c:228 ksys_unshare+0x45d/0xa40 kernel/fork.c:3342 __do_sys_unshare kernel/fork.c:3413 [inline] __se_sys_unshare kernel/fork.c:3411 [inline] __x64_sys_unshare+0x31/0x40 kernel/fork.c:3411 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 21309: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x51/0x70 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+0x2c4/0x4d0 mm/slub.c:4757 afs_free_call+0x303/0x440 fs/afs/rxrpc.c:188 afs_put_call+0x188/0x1e0 fs/afs/rxrpc.c:210 rxrpc_discard_prealloc+0x67b/0x930 net/rxrpc/call_accept.c:224 rxrpc_listen+0x117/0x330 net/rxrpc/af_rxrpc.c:246 afs_close_socket+0x97/0x340 fs/afs/rxrpc.c:113 afs_net_exit+0x93/0x130 fs/afs/main.c:155 ops_exit_list+0xb0/0x180 net/core/net_namespace.c:172 cleanup_net+0x5c6/0xb30 net/core/net_namespace.c:652 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3400 kthread+0x3af/0x750 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 The buggy address belongs to the object at ffff88807c6c3800 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 0 bytes inside of freed 1024-byte region [ffff88807c6c3800, ffff88807c6c3c00) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88807c6c5800 pfn:0x7c6c0 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 ffffea00015db010 ffffea00017ac410 raw: ffff88807c6c5800 000000000010000a 00000000f5000000 0000000000000000 head: 00fff00000000240 ffff88801b041dc0 ffffea00015db010 ffffea00017ac410 head: ffff88807c6c5800 000000000010000a 00000000f5000000 0000000000000000 head: 00fff00000000003 ffffea0001f1b001 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 100, tgid 100 (kworker/0:1H), ts 113095418486, free_ts 113056502852 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x181/0x1b0 mm/page_alloc.c:1551 prep_new_page mm/page_alloc.c:1559 [inline] get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3477 __alloc_frozen_pages_noprof+0x221/0x2470 mm/page_alloc.c:4740 alloc_pages_mpol+0x1fc/0x540 mm/mempolicy.c:2270 alloc_slab_page mm/slub.c:2423 [inline] allocate_slab mm/slub.c:2587 [inline] new_slab+0x23d/0x330 mm/slub.c:2640 ___slab_alloc+0xc5d/0x1720 mm/slub.c:3826 __slab_alloc.constprop.0+0x56/0xb0 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_noprof+0x2ec/0x510 mm/slub.c:4306 kmalloc_noprof include/linux/slab.h:905 [inline] kzalloc_noprof include/linux/slab.h:1037 [inline] ieee802_11_parse_elems_full+0x1d0/0x3240 net/mac80211/parse.c:1013 ieee802_11_parse_elems_crc net/mac80211/ieee80211_i.h:2397 [inline] ieee802_11_parse_elems net/mac80211/ieee80211_i.h:2404 [inline] ieee80211_inform_bss+0xfd/0x1100 net/mac80211/scan.c:79 rdev_inform_bss net/wireless/rdev-ops.h:418 [inline] cfg80211_inform_single_bss_data+0x8f9/0x1df0 net/wireless/scan.c:2367 cfg80211_inform_bss_data+0x205/0x3ba0 net/wireless/scan.c:3222 cfg80211_inform_bss_frame_data+0x272/0x7a0 net/wireless/scan.c:3317 ieee80211_bss_info_update+0x311/0xab0 net/mac80211/scan.c:226 ieee80211_scan_rx+0x474/0xac0 net/mac80211/scan.c:340 __ieee80211_rx_handle_packet net/mac80211/rx.c:5246 [inline] ieee80211_rx_list+0x1bd7/0x2970 net/mac80211/rx.c:5483 page last free pid 6256 tgid 6246 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1127 [inline] free_frozen_pages+0x6db/0xfb0 mm/page_alloc.c:2660 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x4e/0x120 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x69/0x90 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] __kmalloc_cache_noprof+0x243/0x410 mm/slub.c:4320 kmalloc_noprof include/linux/slab.h:901 [inline] kzalloc_noprof include/linux/slab.h:1037 [inline] kobject_uevent_env+0x265/0x1870 lib/kobject_uevent.c:540 __kobject_del+0x168/0x1f0 lib/kobject.c:601 kobject_cleanup lib/kobject.c:680 [inline] kobject_release lib/kobject.c:720 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x327/0x5a0 lib/kobject.c:737 net_rx_queue_update_kobjects+0x478/0x5f0 net/core/net-sysfs.c:1209 remove_queue_kobjects net/core/net-sysfs.c:1984 [inline] netdev_unregister_kobject+0x150/0x270 net/core/net-sysfs.c:2138 unregister_netdevice_many_notify+0x13aa/0x1f30 net/core/dev.c:11923 setup_net+0x4ae/0x860 net/core/net_namespace.c:389 copy_net_ns+0x2a6/0x5f0 net/core/net_namespace.c:516 create_new_namespaces+0x3ea/0xad0 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0xc0/0x1f0 kernel/nsproxy.c:228 ksys_unshare+0x45d/0xa40 kernel/fork.c:3342 Memory state around the buggy address: ffff88807c6c3700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88807c6c3780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88807c6c3800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88807c6c3880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807c6c3900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================