ALSA: firewire-lib: fix uninitialized flag for AV/C deferred transaction

In the Linux kernel, the following vulnerability has been resolved:

ALSA: firewire-lib: fix uninitialized flag for AV/C deferred transaction

AV/C deferred transaction was supported at a commit 00a7bb81c20f ("ALSA:

firewire-lib: Add support for deferred transaction") while 'deferrable'

flag can be uninitialized for non-control/notify AV/C transactions.

UBSAN reports it:

kernel: ================================================================================

kernel: UBSAN: invalid-load in /build/linux-aa0B4d/linux-5.15.0/sound/firewire/fcp.c:363:9

kernel: load of value 158 is not a valid value for type '_Bool'

kernel: CPU: 3 PID: 182227 Comm: irq/35-firewire Tainted: P OE 5.15.0-18-generic #18-Ubuntu

kernel: Hardware name: Gigabyte Technology Co., Ltd. AX370-Gaming 5/AX370-Gaming 5, BIOS F42b 08/01/2019

kernel: Call Trace:

kernel: <IRQ>

kernel: show_stack+0x52/0x58

kernel: dump_stack_lvl+0x4a/0x5f

kernel: dump_stack+0x10/0x12

kernel: ubsan_epilogue+0x9/0x45

kernel: __ubsan_handle_load_invalid_value.cold+0x44/0x49

kernel: fcp_response.part.0.cold+0x1a/0x2b [snd_firewire_lib]

kernel: fcp_response+0x28/0x30 [snd_firewire_lib]

kernel: fw_core_handle_request+0x230/0x3d0 [firewire_core]

kernel: handle_ar_packet+0x1d9/0x200 [firewire_ohci]

kernel: ? handle_ar_packet+0x1d9/0x200 [firewire_ohci]

kernel: ? transmit_complete_callback+0x9f/0x120 [firewire_core]

kernel: ar_context_tasklet+0xa8/0x2e0 [firewire_ohci]

kernel: tasklet_action_common.constprop.0+0xea/0xf0

kernel: tasklet_action+0x22/0x30

kernel: __do_softirq+0xd9/0x2e3

kernel: ? irq_finalize_oneshot.part.0+0xf0/0xf0

kernel: do_softirq+0x75/0xa0

kernel: </IRQ>

kernel: <TASK>

kernel: __local_bh_enable_ip+0x50/0x60

kernel: irq_forced_thread_fn+0x7e/0x90

kernel: irq_thread+0xba/0x190

kernel: ? irq_thread_fn+0x60/0x60

kernel: kthread+0x11e/0x140

kernel: ? irq_thread_check_affinity+0xf0/0xf0

kernel: ? set_kthread_struct+0x50/0x50

kernel: ret_from_fork+0x22/0x30

kernel: </TASK>

kernel: ================================================================================

This commit fixes the bug. The bug has no disadvantage for the non-

control/notify AV/C transactions since the flag has an effect for AV/C

response with INTERIM (0x0f) status which is not used for the transactions

in AV/C general specification.