blob: d63bc158c5204e02305db27f1ad149d14b262cac [file] [log] [blame]
From 50f58db5d46c41b2539828d8a3cc73af42611d74 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Micha=C5=82=20Miros=C5=82aw?= <mirq-linux@rere.qmqm.pl>
Date: Mon, 8 Jun 2020 18:50:39 +0200
Subject: [PATCH] ALSA: pcm: disallow linking stream to itself
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commit 951e2736f4b11b58dc44d41964fa17c3527d882a upstream.
Prevent SNDRV_PCM_IOCTL_LINK linking stream to itself - the code
can't handle it. Fixed commit is not where bug was introduced, but
changes the context significantly.
Cc: stable@vger.kernel.org
Fixes: 0888c321de70 ("pcm_native: switch to fdget()/fdput()")
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Link: https://lore.kernel.org/r/89c4a2487609a0ed6af3ecf01cc972bdc59a7a2d.1591634956.git.mirq-linux@rere.qmqm.pl
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c
index 84ff52fe8ea0..cca448f62e29 100644
--- a/sound/core/pcm_native.c
+++ b/sound/core/pcm_native.c
@@ -1994,6 +1994,12 @@ static int snd_pcm_link(struct snd_pcm_substream *substream, int fd)
}
pcm_file = f.file->private_data;
substream1 = pcm_file->substream;
+
+ if (substream == substream1) {
+ res = -EINVAL;
+ goto _badf;
+ }
+
group = kzalloc(sizeof(*group), GFP_KERNEL);
if (!group) {
res = -ENOMEM;
--
2.27.0