[PATCH] ASoC: audio-graph-card2: fix off by one in graph_parse_node_multi_nm()

From: Dan Carpenter
Date: Mon Dec 04 2023 - 07:42:16 EST


The > comparison should be >= to avoid writing one element beyond the end
of the dai_link->ch_maps[] array. The dai_link->ch_maps[] array is
allocated in graph_parse_node_multi() and it has "nm_max" elements.

Fixes: e2de6808df4a ("ASoC: audio-graph-card2: add CPU:Codec = N:M support")
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
---
In this same function I was also concerned about these conditions:

if (cpu_idx > dai_link->num_cpus)
if (codec_idx > dai_link->num_codecs)

But I wasn't able to see out how those idx variables are actually
used.

sound/soc/generic/audio-graph-card2.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/sound/soc/generic/audio-graph-card2.c b/sound/soc/generic/audio-graph-card2.c
index d9e10308a508..78d9679decda 100644
--- a/sound/soc/generic/audio-graph-card2.c
+++ b/sound/soc/generic/audio-graph-card2.c
@@ -557,7 +557,7 @@ static int graph_parse_node_multi_nm(struct snd_soc_dai_link *dai_link,
struct device_node *mcodec_port;
int codec_idx;

- if (*nm_idx > nm_max)
+ if (*nm_idx >= nm_max)
break;

mcpu_ep_n = of_get_next_child(mcpu_port, mcpu_ep_n);
--
2.42.0