From: Takashi Sakamoto Date: Fri, 25 Jan 2019 13:41:39 +0000 Subject: Re: [PATCH] ALSA: fireface: Off by one in latter_handle_midi_msg() Message-Id: <20190125134139.GA20650@workstation> List-Id: References: <20190125124418.GA21947@kadam> In-Reply-To: <20190125124418.GA21947@kadam> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Dan Carpenter Cc: Clemens Ladisch , alsa-devel@alsa-project.org, kernel-janitors@vger.kernel.org, Takashi Iwai On Fri, Jan 25, 2019 at 03:44:18PM +0300, Dan Carpenter wrote: > The > should be >= or otherwise we potentially read one element beyond > the end of the ff->tx_midi_substreams[] array. > > Fixes: 73f5537fb209 ("ALSA: fireface: support tx MIDI functionality of Fireface UCX") > Signed-off-by: Dan Carpenter > --- > sound/firewire/fireface/ff-protocol-latter.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/sound/firewire/fireface/ff-protocol-latter.c b/sound/firewire/fireface/ff-protocol-latter.c > index 817af4447349..438aeed9a1ab 100644 > --- a/sound/firewire/fireface/ff-protocol-latter.c > +++ b/sound/firewire/fireface/ff-protocol-latter.c > @@ -275,7 +275,7 @@ static void latter_handle_midi_msg(struct snd_ff *ff, unsigned int offset, > struct snd_rawmidi_substream *substream; > unsigned int len; > > - if (index > ff->spec->midi_in_ports) > + if (index >= ff->spec->midi_in_ports) > return; > > switch (data & 0x0000000f) { > -- > 2.17.1 Indeed. The value of index is picked up from quadlet data transferred by device. The range of value is expected to be 0x00 or 0x01, thus this patch is correct. Reviewed-by: Takashi Sakamoto Thanks Takashi Sakamoto