From da1668997052ed1cb00322e1f3b63702615c9429 Mon Sep 17 00:00:00 2001 From: John Keeping Date: Thu, 30 Jan 2025 19:50:34 +0000 Subject: usb: gadget: f_midi: fix MIDI Streaming descriptor lengths While the MIDI jacks are configured correctly, and the MIDIStreaming endpoint descriptors are filled with the correct information, bNumEmbMIDIJack and bLength are set incorrectly in these descriptors. This does not matter when the numbers of in and out ports are equal, but when they differ the host will receive broken descriptors with uninitialized stack memory leaking into the descriptor for whichever value is smaller. The precise meaning of "in" and "out" in the port counts is not clearly defined and can be confusing. But elsewhere the driver consistently uses this to match the USB meaning of IN and OUT viewed from the host, so that "in" ports send data to the host and "out" ports receive data from it. Cc: stable Fixes: c8933c3f79568 ("USB: gadget: f_midi: allow a dynamic number of input and output ports") Signed-off-by: John Keeping Reviewed-by: Takashi Iwai Link: https://lore.kernel.org/r/20250130195035.3883857-1-jkeeping@inmusicbrands.com Signed-off-by: Greg Kroah-Hartman --- drivers/usb/gadget/function/f_midi.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'drivers/usb/gadget') diff --git a/drivers/usb/gadget/function/f_midi.c b/drivers/usb/gadget/function/f_midi.c index 9b991cf5b0f8..47260d65066a 100644 --- a/drivers/usb/gadget/function/f_midi.c +++ b/drivers/usb/gadget/function/f_midi.c @@ -1009,11 +1009,11 @@ static int f_midi_bind(struct usb_configuration *c, struct usb_function *f) } /* configure the endpoint descriptors ... */ - ms_out_desc.bLength = USB_DT_MS_ENDPOINT_SIZE(midi->in_ports); - ms_out_desc.bNumEmbMIDIJack = midi->in_ports; + ms_out_desc.bLength = USB_DT_MS_ENDPOINT_SIZE(midi->out_ports); + ms_out_desc.bNumEmbMIDIJack = midi->out_ports; - ms_in_desc.bLength = USB_DT_MS_ENDPOINT_SIZE(midi->out_ports); - ms_in_desc.bNumEmbMIDIJack = midi->out_ports; + ms_in_desc.bLength = USB_DT_MS_ENDPOINT_SIZE(midi->in_ports); + ms_in_desc.bNumEmbMIDIJack = midi->in_ports; /* ... and add them to the list */ endpoint_descriptor_index = i; -- cgit v1.2.3