[alsa-devel] [PATCH 6/8] ALSA: core: Don't ignore errors at creating proc files

[Takashi Iwai]

We ignore the errors at creating proc files in many places.  But they
should be rather treated seriously.

Also, by assuring the error handling, we can get rid of superfluous
snd_info_free_entry() calls as they will be removed by the parent in
the caller side.

Signed-off-by: Takashi Iwai <tiwai at suse.de>
---
 sound/core/info.c         | 15 ++++++---------
 sound/core/init.c         | 16 +++++++---------
 sound/core/seq/seq_info.c | 17 ++++++++++++++---
 sound/core/sound.c        | 12 ++++--------
 sound/core/sound_oss.c    | 10 ++++------
 5 files changed, 35 insertions(+), 35 deletions(-)

diff --git a/sound/core/info.c b/sound/core/info.c
index 339f90a3aa29..4169062fabf5 100644
--- a/sound/core/info.c
+++ b/sound/core/info.c
@@ -482,10 +482,11 @@ int __init snd_info_init(void)
 	if (!snd_seq_root)
 		goto error;
 #endif
-	snd_info_version_init();
-	snd_minor_info_init();
-	snd_minor_info_oss_init();
-	snd_card_info_init();
+	if (snd_info_version_init() < 0 ||
+	    snd_minor_info_init() < 0 ||
+	    snd_minor_info_oss_init() < 0 ||
+	    snd_card_info_init() < 0)
+		goto error;
 	return 0;
 
  error:
@@ -847,11 +848,7 @@ static int __init snd_info_version_init(void)
 	if (entry == NULL)
 		return -ENOMEM;
 	entry->c.text.read = snd_info_version_read;
-	if (snd_info_register(entry) < 0) {
-		snd_info_free_entry(entry);
-		return -ENOMEM;
-	}
-	return 0;
+	return snd_info_register(entry); /* freed in error path */
 }
 
 #endif /* CONFIG_PROC_FS */
diff --git a/sound/core/init.c b/sound/core/init.c
index 0af34fac0499..769a783757ff 100644
--- a/sound/core/init.c
+++ b/sound/core/init.c
@@ -853,18 +853,16 @@ int __init snd_card_info_init(void)
 	if (! entry)
 		return -ENOMEM;
 	entry->c.text.read = snd_card_info_read;
-	if (snd_info_register(entry) < 0) {
-		snd_info_free_entry(entry);
-		return -ENOMEM;
-	}
+	if (snd_info_register(entry) < 0)
+		return -ENOMEM; /* freed in error path */
 
 #ifdef MODULE
 	entry = snd_info_create_module_entry(THIS_MODULE, "modules", NULL);
-	if (entry) {
-		entry->c.text.read = snd_card_module_info_read;
-		if (snd_info_register(entry) < 0)
-			snd_info_free_entry(entry);
-	}
+	if (!entry)
+		return -ENOMEM;
+	entry->c.text.read = snd_card_module_info_read;
+	if (snd_info_register(entry) < 0)
+		return -ENOMEM; /* freed in error path */
 #endif
 
 	return 0;
diff --git a/sound/core/seq/seq_info.c b/sound/core/seq/seq_info.c
index acf7769419f0..d3c65e780e9e 100644
--- a/sound/core/seq/seq_info.c
+++ b/sound/core/seq/seq_info.c
@@ -51,6 +51,13 @@ create_info_entry(char *name, void (*read)(struct snd_info_entry *,
 	return entry;
 }
 
+static void free_info_entries(void)
+{
+	snd_info_free_entry(queues_entry);
+	snd_info_free_entry(clients_entry);
+	snd_info_free_entry(timer_entry);
+}
+
 /* create all our /proc entries */
 int __init snd_seq_info_init(void)
 {
@@ -59,14 +66,18 @@ int __init snd_seq_info_init(void)
 	clients_entry = create_info_entry("clients",
 					  snd_seq_info_clients_read);
 	timer_entry = create_info_entry("timer", snd_seq_info_timer_read);
+	if (!queues_entry || !clients_entry || !timer_entry)
+		goto error;
 	return 0;
+
+ error:
+	free_info_entries();
+	return -ENOMEM;
 }
 
 int __exit snd_seq_info_done(void)
 {
-	snd_info_free_entry(queues_entry);
-	snd_info_free_entry(clients_entry);
-	snd_info_free_entry(timer_entry);
+	free_info_entries();
 	return 0;
 }
 #endif
diff --git a/sound/core/sound.c b/sound/core/sound.c
index d584944c8fe5..8fc402e4ff35 100644
--- a/sound/core/sound.c
+++ b/sound/core/sound.c
@@ -386,14 +386,10 @@ int __init snd_minor_info_init(void)
 	struct snd_info_entry *entry;
 
 	entry = snd_info_create_module_entry(THIS_MODULE, "devices", NULL);
-	if (entry) {
-		entry->c.text.read = snd_minor_info_read;
-		if (snd_info_register(entry) < 0) {
-			snd_info_free_entry(entry);
-			entry = NULL;
-		}
-	}
-	return 0;
+	if (!entry)
+		return -ENOMEM;
+	entry->c.text.read = snd_minor_info_read;
+	return snd_info_register(entry); /* freed in error path */
 }
 #endif /* CONFIG_PROC_FS */
 
diff --git a/sound/core/sound_oss.c b/sound/core/sound_oss.c
index 5fc3c6534225..56d2f409f1ef 100644
--- a/sound/core/sound_oss.c
+++ b/sound/core/sound_oss.c
@@ -260,12 +260,10 @@ int __init snd_minor_info_oss_init(void)
 	struct snd_info_entry *entry;
 
 	entry = snd_info_create_module_entry(THIS_MODULE, "devices", snd_oss_root);
-	if (entry) {
-		entry->c.text.read = snd_minor_info_oss_read;
-		if (snd_info_register(entry) < 0)
-			snd_info_free_entry(entry);
-	}
-	return 0;
+	if (!entry)
+		return -ENOMEM;
+	entry->c.text.read = snd_minor_info_oss_read;
+	return snd_info_register(entry); /* freed in error path */
 }
 #endif /* CONFIG_PROC_FS */
 
-- 
2.3.5