ALSA: usx2y: Use snd_card_free_when_closed() at disconnection

Vulnerability Description

In the Linux kernel, the following vulnerability has been resolved: ALSA: usx2y: Use snd_card_free_when_closed() at disconnection The USB disconnect callback is supposed to be short and not too-long waiting. OTOH, the current code uses snd_card_free() at disconnection, but this waits for the close of all used fds, hence it can take long. It eventually blocks the upper layer USB ioctls, which may trigger a soft lockup. An easy workaround is to replace snd_card_free() with snd_card_free_when_closed(). This variant returns immediately while the release of resources is done asynchronously by the card device release at the last close.

References

• https://git.kernel.org/stable/c/24fe9f7ca83ec9acf765339054951f5cd9ae5c5d
• https://git.kernel.org/stable/c/befcca1777525e37c659b4129d8ac7463b07ef67
• https://git.kernel.org/stable/c/7bd8838c0ea886679a32834fdcacab296d072fbe
• https://git.kernel.org/stable/c/e07605d855c4104d981653146a330ea48f6266ed
• https://git.kernel.org/stable/c/ffbfc6c4330fc233698529656798bee44fea96f5
• https://git.kernel.org/stable/c/e869642a77a9b3b98b0ab2c8fec7af4385140909
• https://git.kernel.org/stable/c/dafb28f02be407e07a6f679e922a626592b481b0