From 25e8c6ecb46843a955f254b8f0d77894e4a53dc4 Mon Sep 17 00:00:00 2001 From: Artem Egorkine Date: Sun, 25 Dec 2022 12:57:28 +0200 Subject: [PATCH] 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 Cc: Link: https://lore.kernel.org/r/20221225105728.1153989-2-arteme@gmail.com Signed-off-by: Takashi Iwai Signed-off-by: Greg Kroah-Hartman --- sound/usb/line6/midi.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/sound/usb/line6/midi.c b/sound/usb/line6/midi.c index d52355de2bbc0..0838632c788e4 100644 --- a/sound/usb/line6/midi.c +++ b/sound/usb/line6/midi.c @@ -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)