block: drop references taken by class_find_device()

Otherwise we leak references, which is not a good thing to do.


Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 16 insertions, 6 deletions

diff --git a/block/genhd.c b/block/genhd.c
index f34befc54847..656c2c7abf99 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -313,8 +313,10 @@ static void *part_start(struct seq_file *part, loff_t *pos)
 
         mutex_lock(&block_class_lock);
         dev = class_find_device(&block_class, NULL, &k, find_start);
-        if (dev)
+        if (dev) {
+                put_device(dev);
                 return dev_to_disk(dev);
+        }
         return NULL;
 }
 
@@ -331,8 +333,10 @@ static void *part_next(struct seq_file *part, void *v, loff_t *pos)
         struct device *dev;
         ++*pos;
         dev = class_find_device(&block_class, &gp->dev, NULL, find_next);
-        if (dev)
+        if (dev) {
+                put_device(dev);
                 return dev_to_disk(dev);
+        }
         return NULL;
 }
 
@@ -573,8 +577,10 @@ static void *diskstats_start(struct seq_file *part, loff_t *pos)
 
         mutex_lock(&block_class_lock);
         dev = class_find_device(&block_class, NULL, &k, find_start);
-        if (dev)
+        if (dev) {
+                put_device(dev);
                 return dev_to_disk(dev);
+        }
         return NULL;
 }
 
@@ -585,8 +591,10 @@ static void *diskstats_next(struct seq_file *part, void *v, loff_t *pos)
 
         ++*pos;
         dev = class_find_device(&block_class, &gp->dev, NULL, find_next);
-        if (dev)
+        if (dev) {
+                put_device(dev);
                 return dev_to_disk(dev);
+        }
         return NULL;
 }
 
@@ -714,10 +722,12 @@ dev_t blk_lookup_devt(const char *name, int part)
         mutex_lock(&block_class_lock);
         find.name = name;
         find.part = part;
-        dev = class_find_device(&block_class, NULL, (void *)&find, match_id);
-        if (dev)
+        dev = class_find_device(&block_class, NULL, &find, match_id);
+        if (dev) {
+                put_device(dev);
                 devt = MKDEV(MAJOR(dev->devt),
                              MINOR(dev->devt) + part);
+        }
         mutex_unlock(&block_class_lock);
 
         return devt;