CVE-2022-49733

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

ALSA: pcm: oss: Fix race at SNDCTL_DSP_SYNC

There is a small race window at snd_pcm_oss_sync() that is called from

OSS PCM SNDCTL_DSP_SYNC ioctl; namely the function calls

snd_pcm_oss_make_ready() at first, then takes the params_lock mutex

for the rest. When the stream is set up again by another thread

between them, it leads to inconsistency, and may result in unexpected

results such as NULL dereference of OSS buffer as a fuzzer spotted

recently.

The fix is simply to cover snd_pcm_oss_make_ready() call into the same

params_lock mutex with snd_pcm_oss_make_ready_locked() variant.