syzbot

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BUG: KMSAN: use-after-free in hci_cmd_timeout+0x2bd/0x2d0 net/bluetooth/hci_core.c:2637
CPU: 1 PID: 19326 Comm: kworker/1:1 Not tainted 5.5.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events hci_cmd_timeout
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1c9/0x220 lib/dump_stack.c:118
 kmsan_report+0xf8/0x1e0 mm/kmsan/kmsan_report.c:118
 __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:215
 hci_cmd_timeout+0x2bd/0x2d0 net/bluetooth/hci_core.c:2637
 process_one_work+0x1572/0x1ef0 kernel/workqueue.c:2264
 worker_thread+0x111b/0x2460 kernel/workqueue.c:2410
 kthread+0x4b5/0x4f0 kernel/kthread.c:256
 ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:353

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:144 [inline]
 kmsan_internal_poison_shadow+0x5c/0xf0 mm/kmsan/kmsan.c:127
 kmsan_slab_free+0x6e/0xb0 mm/kmsan/kmsan_hooks.c:107
 slab_free_freelist_hook mm/slub.c:1458 [inline]
 slab_free mm/slub.c:3021 [inline]
 kmem_cache_free+0x6cd/0x2d30 mm/slub.c:3037
 kfree_skbmem net/core/skbuff.c:644 [inline]
 __kfree_skb+0x1de/0x240 net/core/skbuff.c:680
 kfree_skb+0x2d3/0x340 net/core/skbuff.c:697
 hci_dev_do_open+0x183f/0x2700 net/bluetooth/hci_core.c:1572
 hci_power_on+0x186/0x910 net/bluetooth/hci_core.c:2193
 process_one_work+0x1572/0x1ef0 kernel/workqueue.c:2264
 worker_thread+0x111b/0x2460 kernel/workqueue.c:2410
 kthread+0x4b5/0x4f0 kernel/kthread.c:256
 ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:353
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