================================================================== BUG: KASAN: slab-use-after-free in hci_uart_write_work+0x2ca/0x550 drivers/bluetooth/hci_ldisc.c:165 Read of size 8 at addr ffff88803210b0d8 by task kworker/0:3/5804 CPU: 0 UID: 0 PID: 5804 Comm: kworker/0:3 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Workqueue: events hci_uart_write_work Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xca/0x240 mm/kasan/report.c:482 kasan_report+0x118/0x150 mm/kasan/report.c:595 hci_uart_write_work+0x2ca/0x550 drivers/bluetooth/hci_ldisc.c:165 process_one_work kernel/workqueue.c:3263 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Allocated by task 11259: kasan_save_stack mm/kasan/common.c:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 unpoison_slab_object mm/kasan/common.c:342 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:368 kasan_slab_alloc include/linux/kasan.h:252 [inline] slab_post_alloc_hook mm/slub.c:4978 [inline] slab_alloc_node mm/slub.c:5288 [inline] kmem_cache_alloc_node_noprof+0x433/0x710 mm/slub.c:5340 __alloc_skb+0x112/0x2d0 net/core/skbuff.c:660 alloc_skb include/linux/skbuff.h:1383 [inline] bt_skb_alloc include/net/bluetooth/bluetooth.h:510 [inline] hci_cmd_sync_alloc+0x3d/0x380 net/bluetooth/hci_sync.c:58 hci_cmd_sync_add net/bluetooth/hci_sync.c:99 [inline] __hci_cmd_sync_sk+0x1a7/0xbc0 net/bluetooth/hci_sync.c:168 __hci_cmd_sync_status_sk net/bluetooth/hci_sync.c:263 [inline] __hci_cmd_sync_status net/bluetooth/hci_sync.c:287 [inline] hci_read_local_features_sync net/bluetooth/hci_sync.c:3708 [inline] hci_init_stage_sync net/bluetooth/hci_sync.c:3623 [inline] hci_init1_sync net/bluetooth/hci_sync.c:3755 [inline] hci_init_sync net/bluetooth/hci_sync.c:4867 [inline] hci_dev_init_sync net/bluetooth/hci_sync.c:5059 [inline] hci_dev_open_sync+0x14be/0x2b60 net/bluetooth/hci_sync.c:5137 hci_dev_do_open net/bluetooth/hci_core.c:430 [inline] hci_power_on+0x1b4/0x680 net/bluetooth/hci_core.c:959 process_one_work kernel/workqueue.c:3263 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 The buggy address belongs to the object at ffff88803210b000 which belongs to the cache skbuff_head_cache of size 240 The buggy address is located 216 bytes inside of freed 240-byte region [ffff88803210b000, ffff88803210b0f0) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x3210b memcg:ffff888077ebcb01 ksm flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000000 ffff8881412cd8c0 ffffea00013b1040 dead000000000003 raw: 0000000000000000 00000000000c000c 00000000f5000000 ffff888077ebcb01 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x52820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 0, tgid 0 (swapper/0), ts 599740704052, free_ts 598294213362 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x234/0x290 mm/page_alloc.c:1845 prep_new_page mm/page_alloc.c:1853 [inline] get_page_from_freelist+0x2365/0x2440 mm/page_alloc.c:3879 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5178 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2416 alloc_slab_page mm/slub.c:3059 [inline] allocate_slab+0x96/0x350 mm/slub.c:3232 new_slab mm/slub.c:3286 [inline] ___slab_alloc+0xf56/0x1990 mm/slub.c:4655 __slab_alloc+0x65/0x100 mm/slub.c:4778 __slab_alloc_node mm/slub.c:4854 [inline] slab_alloc_node mm/slub.c:5276 [inline] kmem_cache_alloc_node_noprof+0x4c5/0x710 mm/slub.c:5340 __alloc_skb+0x112/0x2d0 net/core/skbuff.c:660 skb_copy+0x188/0x800 net/core/skbuff.c:2125 mac80211_hwsim_tx_frame_no_nl+0xcd3/0x11c0 drivers/net/wireless/virtual/mac80211_hwsim.c:1891 mac80211_hwsim_tx_frame+0x1b5/0x200 drivers/net/wireless/virtual/mac80211_hwsim.c:2264 mac80211_hwsim_beacon_tx+0x3f0/0x860 drivers/net/wireless/virtual/mac80211_hwsim.c:2365 __iterate_interfaces+0x2ab/0x590 net/mac80211/util.c:761 ieee80211_iterate_active_interfaces_atomic+0xdb/0x180 net/mac80211/util.c:797 mac80211_hwsim_beacon+0xbb/0x180 drivers/net/wireless/virtual/mac80211_hwsim.c:2395 page last free pid 15 tgid 15 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1394 [inline] __free_frozen_pages+0xbc4/0xd30 mm/page_alloc.c:2901 __tlb_remove_table_free mm/mmu_gather.c:227 [inline] tlb_remove_table_rcu+0x85/0x100 mm/mmu_gather.c:290 rcu_do_batch kernel/rcu/tree.c:2605 [inline] rcu_core+0xcab/0x1770 kernel/rcu/tree.c:2861 handle_softirqs+0x286/0x870 kernel/softirq.c:622 run_ksoftirqd+0x9b/0x100 kernel/softirq.c:1063 smpboot_thread_fn+0x542/0xa60 kernel/smpboot.c:160 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Memory state around the buggy address: ffff88803210af80: fc 00 00 00 00 00 fc fc 00 00 00 00 00 fc fc fc ffff88803210b000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88803210b080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc ^ ffff88803210b100: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb ffff88803210b180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================