At Fri, 11 Jan 2013 08:47:25 +0100, Jens Axboe wrote:

On 2013-01-10 21:19, Takashi Iwai wrote:

...

From: Takashi Iwai tiwai@suse.de Subject: [PATCH v2] ALSA: usb-audio: Fix NULL dereference by access to non-existing substream

The commit [0d9741c0: ALSA: usb-audio: sync ep init fix for audioformat mismatch] introduced the correction of parameters to be set for sync EP. But since the new code assumes that the sync EP is always paired with the data EP of another direction, it triggers Oops when a device only with a single direction is used.

This patch adds a proper check of sync EP type and the presence of the paired substream for avoiding the crash.

Reported-by: Jens Axboe axboe@kernel.dk Signed-off-by: Takashi Iwai tiwai@suse.de

Confirmed, it works. You can add my tested-by too. Thanks Takashi!

Thanks for quick testing. Applied it now.

Takashi