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BUG: KASAN: slab-use-after-free in hci_uart_write_work+0x82d/0x960 drivers/bluetooth/hci_ldisc.c:165
Read of size 4 at addr ffff888051a89d30 by task kworker/0:0/9

CPU: 0 UID: 0 PID: 9 Comm: kworker/0:0 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Workqueue: events hci_uart_write_work
Call Trace:
 <TASK>
 __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:378 [inline]
 print_report+0xcd/0x630 mm/kasan/report.c:482
 kasan_report+0xe0/0x110 mm/kasan/report.c:595
 hci_uart_write_work+0x82d/0x960 drivers/bluetooth/hci_ldisc.c:165
 process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257
 process_scheduled_works kernel/workqueue.c:3340 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421
 kthread+0x3c5/0x780 kernel/kthread.c:463
 ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
 </TASK>

Allocated by task 24:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:56
 kasan_save_track+0x14/0x30 mm/kasan/common.c:77
 unpoison_slab_object mm/kasan/common.c:339 [inline]
 __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:365
 kasan_slab_alloc include/linux/kasan.h:252 [inline]
 slab_post_alloc_hook mm/slub.c:4953 [inline]
 slab_alloc_node mm/slub.c:5263 [inline]
 kmem_cache_alloc_node_noprof+0x298/0x800 mm/slub.c:5315
 __alloc_skb+0x156/0x410 net/core/skbuff.c:679
 alloc_skb include/linux/skbuff.h:1383 [inline]
 bcsp_prepare_pkt+0xe0/0xae0 drivers/bluetooth/hci_bcsp.c:218
 bcsp_dequeue+0x237/0x4b0 drivers/bluetooth/hci_bcsp.c:308
 hci_uart_dequeue drivers/bluetooth/hci_ldisc.c:107 [inline]
 hci_uart_write_work+0x4e3/0x960 drivers/bluetooth/hci_ldisc.c:161
 process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257
 process_scheduled_works kernel/workqueue.c:3340 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421
 kthread+0x3c5/0x780 kernel/kthread.c:463
 ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246

The buggy address belongs to the object at ffff888051a89cc0
 which belongs to the cache skbuff_head_cache of size 240
The buggy address is located 112 bytes inside of
 freed 240-byte region [ffff888051a89cc0, ffff888051a89db0)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888051a88500 pfn:0x51a88
head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
memcg:ffff88804b1d9001
flags: 0x4fff00000000240(workingset|head|node=1|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 04fff00000000240 ffff88801c3e48c0 ffffea0001bac690 ffffea0001d04990
raw: ffff888051a88500 0000000000190009 00000000f5000000 ffff88804b1d9001
head: 04fff00000000240 ffff88801c3e48c0 ffffea0001bac690 ffffea0001d04990
head: ffff888051a88500 0000000000190009 00000000f5000000 ffff88804b1d9001
head: 04fff00000000001 ffffea000146a201 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000002
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 1, migratetype Unmovable, gfp_mask 0x52820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 23, tgid 23 (ksoftirqd/2), ts 50075803359, free_ts 34434501663
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1af/0x220 mm/page_alloc.c:1846
 prep_new_page mm/page_alloc.c:1854 [inline]
 get_page_from_freelist+0xd0b/0x31a0 mm/page_alloc.c:3915
 __alloc_frozen_pages_noprof+0x25f/0x2430 mm/page_alloc.c:5210
 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2486
 alloc_slab_page mm/slub.c:3075 [inline]
 allocate_slab mm/slub.c:3248 [inline]
 new_slab+0x2c3/0x430 mm/slub.c:3302
 ___slab_alloc+0xe18/0x1c90 mm/slub.c:4656
 __kmem_cache_alloc_bulk+0x1fb/0x6c0 mm/slub.c:7429
 kmem_cache_alloc_bulk_noprof+0x4e1/0x800 mm/slub.c:7495
 napi_skb_cache_get+0x6ac/0x900 net/core/skbuff.c:291
 __alloc_skb+0x2aa/0x410 net/core/skbuff.c:668
 napi_alloc_skb+0x44b/0x820 net/core/skbuff.c:832
 e1000_alloc_rx_skb drivers/net/ethernet/intel/e1000/e1000_main.c:4115 [inline]
 e1000_copybreak drivers/net/ethernet/intel/e1000/e1000_main.c:4331 [inline]
 e1000_clean_rx_irq+0x2ae/0x1180 drivers/net/ethernet/intel/e1000/e1000_main.c:4383
 e1000_clean+0x9cb/0x2670 drivers/net/ethernet/intel/e1000/e1000_main.c:3806
 __napi_poll.constprop.0+0xb3/0x540 net/core/dev.c:7666
 napi_poll net/core/dev.c:7729 [inline]
 net_rx_action+0x9f9/0xfa0 net/core/dev.c:7881
 handle_softirqs+0x219/0x950 kernel/softirq.c:622
page last free pid 5655 tgid 5655 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1395 [inline]
 __free_frozen_pages+0x7df/0x1170 mm/page_alloc.c:2943
 discard_slab mm/slub.c:3346 [inline]
 __put_partials+0x130/0x170 mm/slub.c:3886
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x4c/0xf0 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:349
 kasan_slab_alloc include/linux/kasan.h:252 [inline]
 slab_post_alloc_hook mm/slub.c:4953 [inline]
 slab_alloc_node mm/slub.c:5263 [inline]
 kmem_cache_alloc_node_noprof+0x298/0x800 mm/slub.c:5315
 __alloc_skb+0x156/0x410 net/core/skbuff.c:679
 alloc_skb include/linux/skbuff.h:1383 [inline]
 alloc_skb_with_frags+0xe0/0x860 net/core/skbuff.c:6712
 sock_alloc_send_pskb+0x7f9/0x980 net/core/sock.c:2995
 unix_dgram_sendmsg+0x3bc/0x1830 net/unix/af_unix.c:2130
 unix_seqpacket_sendmsg+0x12a/0x1c0 net/unix/af_unix.c:2531
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg net/socket.c:742 [inline]
 sock_write_iter+0x566/0x610 net/socket.c:1195
 new_sync_write fs/read_write.c:593 [inline]
 vfs_write+0x7d3/0x11d0 fs/read_write.c:686
 ksys_write+0x1f8/0x250 fs/read_write.c:738
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff888051a89c00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc
 ffff888051a89c80: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb
>ffff888051a89d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                     ^
 ffff888051a89d80: fb fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc
 ffff888051a89e00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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