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BUG: KMSAN: uninit-value in bcsp_close+0x127/0x1e0 drivers/bluetooth/hci_bcsp.c:748
CPU: 1 PID: 12579 Comm: syz-executor.5 Not tainted 5.3.0-rc7+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x191/0x1f0 lib/dump_stack.c:113
 kmsan_report+0x13a/0x2b0 mm/kmsan/kmsan_report.c:108
 __msan_warning+0x73/0xe0 mm/kmsan/kmsan_instr.c:250
 skb_unref include/linux/skbuff.h:1017 [inline]
 kfree_skb+0x23c/0x4c0 net/core/skbuff.c:693
 bcsp_close+0x127/0x1e0 drivers/bluetooth/hci_bcsp.c:748
 hci_uart_tty_close+0x385/0x410 drivers/bluetooth/hci_ldisc.c:548
 tty_ldisc_close drivers/tty/tty_ldisc.c:494 [inline]
 tty_ldisc_kill drivers/tty/tty_ldisc.c:642 [inline]
 tty_ldisc_release+0x5dd/0xdb0 drivers/tty/tty_ldisc.c:814
 tty_release_struct+0x4f/0x1d0 drivers/tty/tty_io.c:1612
 tty_release+0x1be2/0x1e80 drivers/tty/tty_io.c:1785
 __fput+0x4c9/0xba0 fs/file_table.c:280
 ____fput+0x37/0x40 fs/file_table.c:313
 task_work_run+0x22e/0x2a0 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_usermode_loop arch/x86/entry/common.c:163 [inline]
 prepare_exit_to_usermode+0x39d/0x4d0 arch/x86/entry/common.c:194
 syscall_return_slowpath+0x90/0x610 arch/x86/entry/common.c:274
 do_syscall_64+0xe2/0xf0 arch/x86/entry/common.c:300
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
RIP: 0033:0x413711
Code: 75 14 b8 03 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 04 1b 00 00 c3 48 83 ec 08 e8 0a fc ff ff 48 89 04 24 b8 03 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 53 fc ff ff 48 89 d0 48 83 c4 08 48 3d 01
RSP: 002b:0000000000a6fbf0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000005 RCX: 0000000000413711
RDX: 0000000000000000 RSI: 000000000000021d RDI: 0000000000000004
RBP: 0000000000000001 R08: 000000001473c21d R09: 000000001473c221
R10: 0000000000a6fcd0 R11: 0000000000000293 R12: 000000000075c9a0
R13: 000000000075c9a0 R14: 0000000000761608 R15: 000000000075bfd4

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:150 [inline]
 kmsan_internal_poison_shadow+0x53/0x100 mm/kmsan/kmsan.c:134
 kmsan_slab_free+0x8d/0x100 mm/kmsan/kmsan_hooks.c:123
 slab_free_freelist_hook mm/slub.c:1472 [inline]
 slab_free mm/slub.c:3038 [inline]
 kmem_cache_free_bulk+0x3ad9/0x3f50 mm/slub.c:3163
 __kfree_skb_flush+0xb0/0x100 net/core/skbuff.c:862
 net_rx_action+0x1908/0x1950 net/core/dev.c:6441
 __do_softirq+0x4a1/0x83a kernel/softirq.c:293
 invoke_softirq kernel/softirq.c:375 [inline]
 irq_exit+0x230/0x280 kernel/softirq.c:416
 exiting_irq arch/x86/include/asm/apic.h:537 [inline]
 do_IRQ+0x20d/0x3a0 arch/x86/kernel/irq.c:259
 ret_from_intr+0x0/0x33
 native_safe_halt arch/x86/include/asm/irqflags.h:60 [inline]
 arch_safe_halt arch/x86/include/asm/irqflags.h:103 [inline]
 default_idle+0x53/0x90 arch/x86/kernel/process.c:580
 arch_cpu_idle+0x25/0x30 arch/x86/kernel/process.c:571
 default_idle_call kernel/sched/idle.c:94 [inline]
 cpuidle_idle_call kernel/sched/idle.c:154 [inline]
 do_idle+0x1d7/0x790 kernel/sched/idle.c:263
 cpu_startup_entry+0x45/0x50 kernel/sched/idle.c:354
 rest_init+0x1be/0x1f0 init/main.c:452
 arch_call_rest_init+0x13/0x15
 start_kernel+0x991/0xb61 init/main.c:788
 x86_64_start_reservations+0x18/0x2e arch/x86/kernel/head64.c:472
 x86_64_start_kernel+0x81/0x84 arch/x86/kernel/head64.c:453
 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:241
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