CVE-2022-49248

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> ALSA: firewire-lib: fix uninitialized flag for AV/C deferred transaction<br /> <br /> AV/C deferred transaction was supported at a commit 00a7bb81c20f ("ALSA:<br /> firewire-lib: Add support for deferred transaction") while &amp;#39;deferrable&amp;#39;<br /> flag can be uninitialized for non-control/notify AV/C transactions.<br /> UBSAN reports it:<br /> <br /> kernel: ================================================================================<br /> kernel: UBSAN: invalid-load in /build/linux-aa0B4d/linux-5.15.0/sound/firewire/fcp.c:363:9<br /> kernel: load of value 158 is not a valid value for type &amp;#39;_Bool&amp;#39;<br /> kernel: CPU: 3 PID: 182227 Comm: irq/35-firewire Tainted: P OE 5.15.0-18-generic #18-Ubuntu<br /> kernel: Hardware name: Gigabyte Technology Co., Ltd. AX370-Gaming 5/AX370-Gaming 5, BIOS F42b 08/01/2019<br /> kernel: Call Trace:<br /> kernel: <br /> kernel: show_stack+0x52/0x58<br /> kernel: dump_stack_lvl+0x4a/0x5f<br /> kernel: dump_stack+0x10/0x12<br /> kernel: ubsan_epilogue+0x9/0x45<br /> kernel: __ubsan_handle_load_invalid_value.cold+0x44/0x49<br /> kernel: fcp_response.part.0.cold+0x1a/0x2b [snd_firewire_lib]<br /> kernel: fcp_response+0x28/0x30 [snd_firewire_lib]<br /> kernel: fw_core_handle_request+0x230/0x3d0 [firewire_core]<br /> kernel: handle_ar_packet+0x1d9/0x200 [firewire_ohci]<br /> kernel: ? handle_ar_packet+0x1d9/0x200 [firewire_ohci]<br /> kernel: ? transmit_complete_callback+0x9f/0x120 [firewire_core]<br /> kernel: ar_context_tasklet+0xa8/0x2e0 [firewire_ohci]<br /> kernel: tasklet_action_common.constprop.0+0xea/0xf0<br /> kernel: tasklet_action+0x22/0x30<br /> kernel: __do_softirq+0xd9/0x2e3<br /> kernel: ? irq_finalize_oneshot.part.0+0xf0/0xf0<br /> kernel: do_softirq+0x75/0xa0<br /> kernel: <br /> kernel: <br /> kernel: __local_bh_enable_ip+0x50/0x60<br /> kernel: irq_forced_thread_fn+0x7e/0x90<br /> kernel: irq_thread+0xba/0x190<br /> kernel: ? irq_thread_fn+0x60/0x60<br /> kernel: kthread+0x11e/0x140<br /> kernel: ? irq_thread_check_affinity+0xf0/0xf0<br /> kernel: ? set_kthread_struct+0x50/0x50<br /> kernel: ret_from_fork+0x22/0x30<br /> kernel: <br /> kernel: ================================================================================<br /> <br /> This commit fixes the bug. The bug has no disadvantage for the non-<br /> control/notify AV/C transactions since the flag has an effect for AV/C<br /> response with INTERIM (0x0f) status which is not used for the transactions<br /> in AV/C general specification.