[alsa-devel] [patch] ALSA: pcm: add more format names

Dan Carpenter error27 at gmail.com
Fri Aug 27 22:02:15 CEST 2010

There were some new formats added in commit 15c0cee6c809 "ALSA: pcm:
Define G723 3-bit and 5-bit formats".  That commit increased
SNDRV_PCM_FORMAT_LAST as well.  My concern is that there are a couple
places which do:

        for (i = 0; i < SNDRV_PCM_FORMAT_LAST; i++) {
                if (dummy->pcm_hw.formats & (1ULL << i))
                        snd_iprintf(buffer, " %s", snd_pcm_format_name(i));

I haven't tested these but it looks like if "i" were equal to
SNDRV_PCM_FORMAT_G723_24 or higher then we might read past the end of
the array. 

Signed-off-by: Dan Carpenter <error27 at gmail.com>
Resending because I screwed up the CC lis on my first mail.

diff --git a/sound/core/pcm.c b/sound/core/pcm.c
index cbe815d..204af48 100644
--- a/sound/core/pcm.c
+++ b/sound/core/pcm.c
@@ -203,10 +203,16 @@ static char *snd_pcm_format_names[] = {
+	FORMAT(G723_24),
+	FORMAT(G723_24_1B),
+	FORMAT(G723_40),
+	FORMAT(G723_40_1B),
 const char *snd_pcm_format_name(snd_pcm_format_t format)
+	if (format >= ARRAY_SIZE(snd_pcm_format_names))
+		return "Unknown";
 	return snd_pcm_format_names[format];

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