From a0830dbd4e42b38aefdf3fb61ba5019a1a99ea85 Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Tue, 16 Oct 2012 13:05:59 +0200 Subject: ALSA: Add a reference counter to card instance For more strict protection for wild disconnections, a refcount is introduced to the card instance, and let it up/down when an object is referred via snd_lookup_*() in the open ops. The free-after-last-close check is also changed to check this refcount instead of the empty list, too. Reported-by: Matthieu CASTET Cc: Signed-off-by: Takashi Iwai --- sound/core/oss/pcm_oss.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'sound/core/oss/pcm_oss.c') diff --git a/sound/core/oss/pcm_oss.c b/sound/core/oss/pcm_oss.c index 08fde0060fd9..2529e01538e9 100644 --- a/sound/core/oss/pcm_oss.c +++ b/sound/core/oss/pcm_oss.c @@ -2457,6 +2457,8 @@ static int snd_pcm_oss_open(struct inode *inode, struct file *file) __error2: snd_card_file_remove(pcm->card, file); __error1: + if (pcm) + snd_card_unref(pcm->card); return err; } -- cgit v1.2.2 From 0914f7961babbf28aaa2f19b453951fb4841c03f Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Tue, 16 Oct 2012 16:43:39 +0200 Subject: ALSA: Avoid endless sleep after disconnect When disconnect callback is called, each component should wake up sleepers and check card->shutdown flag for avoiding the endless sleep blocking the proper resource release. Cc: Signed-off-by: Takashi Iwai --- sound/core/oss/pcm_oss.c | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'sound/core/oss/pcm_oss.c') diff --git a/sound/core/oss/pcm_oss.c b/sound/core/oss/pcm_oss.c index 2529e01538e9..f337b66a020b 100644 --- a/sound/core/oss/pcm_oss.c +++ b/sound/core/oss/pcm_oss.c @@ -2441,6 +2441,10 @@ static int snd_pcm_oss_open(struct inode *inode, struct file *file) mutex_unlock(&pcm->open_mutex); schedule(); mutex_lock(&pcm->open_mutex); + if (pcm->card->shutdown) { + err = -ENODEV; + break; + } if (signal_pending(current)) { err = -ERESTARTSYS; break; -- cgit v1.2.2 From 8bb4d9ce08b0a92ca174e41d92c180328f86173f Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Thu, 8 Nov 2012 14:36:18 +0100 Subject: ALSA: Fix card refcount unbalance There are uncovered cases whether the card refcount introduced by the commit a0830dbd isn't properly increased or decreased: - OSS PCM and mixer success paths - When lookup function gets NULL This patch fixes these places. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=50251 Cc: Signed-off-by: Takashi Iwai --- sound/core/oss/pcm_oss.c | 1 + 1 file changed, 1 insertion(+) (limited to 'sound/core/oss/pcm_oss.c') diff --git a/sound/core/oss/pcm_oss.c b/sound/core/oss/pcm_oss.c index f337b66a020b..4c1cc51772e6 100644 --- a/sound/core/oss/pcm_oss.c +++ b/sound/core/oss/pcm_oss.c @@ -2454,6 +2454,7 @@ static int snd_pcm_oss_open(struct inode *inode, struct file *file) mutex_unlock(&pcm->open_mutex); if (err < 0) goto __error; + snd_card_unref(pcm->card); return err; __error: -- cgit v1.2.2