[PATCH 4.9 003/103] sound: fix a memory leak bug

From: Greg Kroah-Hartman
Date: Thu Aug 22 2019 - 13:43:41 EST


From: Wenwen Wang <wenwen@xxxxxxxxxx>

commit c7cd7c748a3250ca33509f9235efab9c803aca09 upstream.

In sound_insert_unit(), the controlling structure 's' is allocated through
kmalloc(). Then it is added to the sound driver list by invoking
__sound_insert_unit(). Later on, if __register_chrdev() fails, 's' is
removed from the list through __sound_remove_unit(). If 'index' is not less
than 0, -EBUSY is returned to indicate the error. However, 's' is not
deallocated on this execution path, leading to a memory leak bug.

To fix the above issue, free 's' before -EBUSY is returned.

Signed-off-by: Wenwen Wang <wenwen@xxxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
sound/sound_core.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

--- a/sound/sound_core.c
+++ b/sound/sound_core.c
@@ -287,7 +287,8 @@ retry:
goto retry;
}
spin_unlock(&sound_loader_lock);
- return -EBUSY;
+ r = -EBUSY;
+ goto fail;
}
}