From: Takashi Iwai Date: Fri, 30 Sep 2022 10:01:29 +0000 (+0200) Subject: ALSA: usb-audio: Fix NULL dererence at error path X-Git-Tag: v5.19.17~712 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=3965d9b056676b3538f9835752c45c49d630558b;p=thirdparty%2Fkernel%2Fstable.git ALSA: usb-audio: Fix NULL dererence at error path commit 568be8aaf8a535f79c4db76cabe17b035aa2584d upstream. At an error path to release URB buffers and contexts, the driver might hit a NULL dererence for u->urb pointer, when u->buffer_size has been already set but the actual URB allocation failed. Fix it by adding the NULL check of urb. Also, make sure that buffer_size is cleared after the error path or the close. Cc: Reported-by: Sabri N. Ferreiro Link: https://lore.kernel.org/r/CAKG+3NRjTey+fFfUEGwuxL-pi_=T4cUskYG9OzpzHytF+tzYng@mail.gmail.com Link: https://lore.kernel.org/r/20220930100129.19445-1-tiwai@suse.de Signed-off-by: Takashi Iwai Signed-off-by: Greg Kroah-Hartman --- diff --git a/sound/usb/endpoint.c b/sound/usb/endpoint.c index 15bc56feda72d..7a7f5ebafe4aa 100644 --- a/sound/usb/endpoint.c +++ b/sound/usb/endpoint.c @@ -93,12 +93,13 @@ static inline unsigned get_usb_high_speed_rate(unsigned int rate) */ static void release_urb_ctx(struct snd_urb_ctx *u) { - if (u->buffer_size) + if (u->urb && u->buffer_size) usb_free_coherent(u->ep->chip->dev, u->buffer_size, u->urb->transfer_buffer, u->urb->transfer_dma); usb_free_urb(u->urb); u->urb = NULL; + u->buffer_size = 0; } static const char *usb_error_string(int err)