alsa-devel.alsa-project.org archive mirror
 help / color / mirror / Atom feed
* [PATCH] pcm: fix buffer overflow in snd_pcm_chmap_print()
@ 2014-12-30 18:46 Anssi Hannula
  2014-12-31  9:03 ` Takashi Iwai
  0 siblings, 1 reply; 2+ messages in thread
From: Anssi Hannula @ 2014-12-30 18:46 UTC (permalink / raw)
  To: Takashi Iwai; +Cc: alsa-devel

The size argument is wrong for one of the snprintf() calls in
snd_pcm_chmap_print(), allowing an overflow to happen (the user-provided
buffer may be written data up to 2x its actual size).

Seen in an user report here: http://trac.kodi.tv/ticket/15641

Signed-off-by: Anssi Hannula <anssi.hannula@iki.fi>
---
 src/pcm/pcm.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/pcm/pcm.c b/src/pcm/pcm.c
index baa47c7..e74e02f 100644
--- a/src/pcm/pcm.c
+++ b/src/pcm/pcm.c
@@ -7621,7 +7621,7 @@ int snd_pcm_chmap_print(const snd_pcm_chmap_t *map, size_t maxlen, char *buf)
 				return -ENOMEM;
 		}
 		if (map->pos[i] & SND_CHMAP_DRIVER_SPEC)
-			len += snprintf(buf + len, maxlen, "%d", p);
+			len += snprintf(buf + len, maxlen - len, "%d", p);
 		else {
 			const char *name = chmap_names[p];
 			if (name)
-- 
1.8.4.5

^ permalink raw reply related	[flat|nested] 2+ messages in thread

* Re: [PATCH] pcm: fix buffer overflow in snd_pcm_chmap_print()
  2014-12-30 18:46 [PATCH] pcm: fix buffer overflow in snd_pcm_chmap_print() Anssi Hannula
@ 2014-12-31  9:03 ` Takashi Iwai
  0 siblings, 0 replies; 2+ messages in thread
From: Takashi Iwai @ 2014-12-31  9:03 UTC (permalink / raw)
  To: Anssi Hannula; +Cc: alsa-devel

At Tue, 30 Dec 2014 20:46:11 +0200,
Anssi Hannula wrote:
> 
> The size argument is wrong for one of the snprintf() calls in
> snd_pcm_chmap_print(), allowing an overflow to happen (the user-provided
> buffer may be written data up to 2x its actual size).
> 
> Seen in an user report here: http://trac.kodi.tv/ticket/15641
> 
> Signed-off-by: Anssi Hannula <anssi.hannula@iki.fi>

Thanks, applied.


Takashi

> ---
>  src/pcm/pcm.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/src/pcm/pcm.c b/src/pcm/pcm.c
> index baa47c7..e74e02f 100644
> --- a/src/pcm/pcm.c
> +++ b/src/pcm/pcm.c
> @@ -7621,7 +7621,7 @@ int snd_pcm_chmap_print(const snd_pcm_chmap_t *map, size_t maxlen, char *buf)
>  				return -ENOMEM;
>  		}
>  		if (map->pos[i] & SND_CHMAP_DRIVER_SPEC)
> -			len += snprintf(buf + len, maxlen, "%d", p);
> +			len += snprintf(buf + len, maxlen - len, "%d", p);
>  		else {
>  			const char *name = chmap_names[p];
>  			if (name)
> -- 
> 1.8.4.5
> 

^ permalink raw reply	[flat|nested] 2+ messages in thread

end of thread, other threads:[~2014-12-31  9:03 UTC | newest]

Thread overview: 2+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2014-12-30 18:46 [PATCH] pcm: fix buffer overflow in snd_pcm_chmap_print() Anssi Hannula
2014-12-31  9:03 ` Takashi Iwai

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).