releases/2.6.26.2/sound-ensure-device-number-is-valid-in-snd_seq_oss_synth_make_info.patch

From stable-bounces@linux.kernel.org Mon Aug  4 17:20:12 2008
From: Willy Tarreau <w@1wt.eu>
Date: Tue, 5 Aug 2008 00:20:03 GMT
Subject: sound: ensure device number is valid in snd_seq_oss_synth_make_info
To: jejb@kernel.org, stable@kernel.org
Message-ID: <200808050020.m750K3ii020082@hera.kernel.org>

From: Willy Tarreau <w@1wt.eu>

commit 82e68f7ffec3800425f2391c8c86277606860442 upstream

snd_seq_oss_synth_make_info() incorrectly reports information
to userspace without first checking for the validity of the
device number, leading to possible information leak (CVE-2008-3272).

Reported-By: Tobias Klein <tk@trapkit.de>
Acked-and-tested-by: Takashi Iwai <tiwai@suse.de>
Cc: stable@kernel.org
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
 sound/core/seq/oss/seq_oss_synth.c |    3 +++
 1 file changed, 3 insertions(+)

--- a/sound/core/seq/oss/seq_oss_synth.c
+++ b/sound/core/seq/oss/seq_oss_synth.c
@@ -604,6 +604,9 @@ snd_seq_oss_synth_make_info(struct seq_o
 {
 	struct seq_oss_synth *rec;
 
+	if (dev < 0 || dev >= dp->max_synthdev)
+		return -ENXIO;
+
 	if (dp->synths[dev].is_midi) {
 		struct midi_info minf;
 		snd_seq_oss_midi_make_info(dp, dp->synths[dev].midi_mapped, &minf);