Commit 25e8c6ec authored Dec 25, 2022 by Artem Egorkine Committed by Greg Kroah-Hartman Jan 18, 2023

ALSA: line6: fix stack overflow in line6_midi_transmit



commit b8800d324abb50160560c636bfafe2c81001b66c upstream.

Correctly calculate available space including the size of the chunk
buffer. This fixes a buffer overflow when multiple MIDI sysex
messages are sent to a PODxt device.

Signed-off-by: Artem Egorkine <arteme@gmail.com>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20221225105728.1153989-2-arteme@gmail.com


Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 10a07d81

sound/usb/line6/midi.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -44,7 +44,8 @@ static void line6_midi_transmit(struct snd_rawmidi_substream *substream)
		int req, done;

		for (;;) {
		req = min(line6_midibuf_bytes_free(mb), line6->max_packet_size);
		req = min3(line6_midibuf_bytes_free(mb), line6->max_packet_size,
		LINE6_FALLBACK_MAXPACKETSIZE);
		done = snd_rawmidi_transmit_peek(substream, chunk, req);

		if (done == 0)