ASoC: core: Fix use-after-free in snd_soc_exit()

Vulnerability Description

In the Linux kernel, the following vulnerability has been resolved: ASoC: core: Fix use-after-free in snd_soc_exit() KASAN reports a use-after-free: BUG: KASAN: use-after-free in device_del+0xb5b/0xc60 Read of size 8 at addr ffff888008655050 by task rmmod/387 CPU: 2 PID: 387 Comm: rmmod Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) Call Trace: <TASK> dump_stack_lvl+0x79/0x9a print_report+0x17f/0x47b kasan_report+0xbb/0xf0 device_del+0xb5b/0xc60 platform_device_del.part.0+0x24/0x200 platform_device_unregister+0x2e/0x40 snd_soc_exit+0xa/0x22 [snd_soc_core] __do_sys_delete_module.constprop.0+0x34f/0x5b0 do_syscall_64+0x3a/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd ... </TASK> It's bacause in snd_soc_init(), snd_soc_util_init() is possble to fail, but its ret is ignored, which makes soc_dummy_dev unregistered twice. snd_soc_init() snd_soc_util_init() platform_device_register_simple(soc_dummy_dev) platform_driver_register() # fail platform_device_unregister(soc_dummy_dev) platform_driver_register() # success ... snd_soc_exit() snd_soc_util_exit() # soc_dummy_dev will be unregistered for second time To fix it, handle error and stop snd_soc_init() when util_init() fail. Also clean debugfs when util_init() or driver_register() fail.

References

• https://git.kernel.org/stable/c/41fad4f712e081acdfde8b59847f9f66eaf407a0
• https://git.kernel.org/stable/c/90bbdf30a51e42378cb23a312005a022794b8e1e
• https://git.kernel.org/stable/c/a3365e62239dc064019a244bde5686ac18527c22
• https://git.kernel.org/stable/c/2ec3f558db343b045a7c7419cdbaec266b8ac1a7
• https://git.kernel.org/stable/c/8d21554ec7680e9585fb852d933203c3db60dad1
• https://git.kernel.org/stable/c/34eee4189bcebbd5f6a2ff25ef0cb893ad33d51e
• https://git.kernel.org/stable/c/c5674bd073c0fd9f620ca550c5ff08d0d429bdd9
• https://git.kernel.org/stable/c/6ec27c53886c8963729885bcf2dd996eba2767a7