From: Takashi Iwai <tiwai@xxxxxxx> 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: <stable@xxxxxxxxxxxxxxx> Reported-by: Sabri N. Ferreiro <snferreiro1@xxxxxxxxx> Link: https://lore.kernel.org/r/CAKG+3NRjTey+fFfUEGwuxL-pi_=T4cUskYG9OzpzHytF+tzYng@xxxxxxxxxxxxxx Link: https://lore.kernel.org/r/20220930100129.19445-1-tiwai@xxxxxxx Signed-off-by: Takashi Iwai <tiwai@xxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- sound/usb/endpoint.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/sound/usb/endpoint.c +++ b/sound/usb/endpoint.c @@ -93,12 +93,13 @@ static inline unsigned get_usb_high_spee */ 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)
