GCC 12 sees that it's technically possible for num_streams to be larger
than ARRAY_SIZE(pcm->streams). Bounds-check the iterator.
../sound/pci/lola/lola_pcm.c: In function 'lola_pcm_update':
../sound/pci/lola/lola_pcm.c:567:64: warning: array subscript [0, 31] is outside array bounds of 'struct lola_stream[16]' [-Warray-bounds]
567 | struct lola_stream *str = &pcm->streams[i];
| ~~~~~~~~~~~~^~~
In file included from ../sound/pci/lola/lola_pcm.c:15:
../sound/pci/lola/lola.h:307:28: note: while referencing 'streams'
307 | struct lola_stream streams[MAX_STREAM_COUNT];
| ^~~~~~~
Cc: Jaroslav Kysela <perex@xxxxxxxx>
Cc: Takashi Iwai <tiwai@xxxxxxxx>
Cc: alsa-devel@xxxxxxxxxxxxxxxx
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
---
sound/pci/lola/lola_pcm.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/sound/pci/lola/lola_pcm.c b/sound/pci/lola/lola_pcm.c
index 738ec987000a..32193fae978d 100644
--- a/sound/pci/lola/lola_pcm.c
+++ b/sound/pci/lola/lola_pcm.c
@@ -561,8 +561,9 @@ static snd_pcm_uframes_t lola_pcm_pointer(struct snd_pcm_substream *substream)
void lola_pcm_update(struct lola *chip, struct lola_pcm *pcm, unsigned int bits)
{
int i;
+ u8 num_streams = min_t(u8, pcm->num_streams, ARRAY_SIZE(pcm->streams));
- for (i = 0; bits && i < pcm->num_streams; i++) {
+ for (i = 0; bits && i < num_streams; i++) {
if (bits & (1 << i)) {
struct lola_stream *str = &pcm->streams[i];
if (str->substream && str->running)
--
2.32.0
