[PATCH] stm class: fix device leak in open error path

[Johan Hovold]

Make sure to drop the reference taken by class_find_device() also on
allocation errors in open().

Fixes: 7bd1d4093c2f ("stm class: Introduce an abstraction for...")
Signed-off-by: Johan Hovold <jo...@kernel.org>
---
 drivers/hwtracing/stm/core.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/drivers/hwtracing/stm/core.c b/drivers/hwtracing/stm/core.c
index 51f81d64ca37..47811f5c9bc9 100644
--- a/drivers/hwtracing/stm/core.c
+++ b/drivers/hwtracing/stm/core.c
@@ -368,8 +368,10 @@ static int stm_char_open(struct inode *inode, struct file 
*file)
                return -ENODEV;
 
        stmf = kzalloc(sizeof(*stmf), GFP_KERNEL);
-       if (!stmf)
-               return -ENOMEM;
+       if (!stmf) {
+               err = -ENOMEM;
+               goto err_put_device;
+       }
 
        stm_output_init(&stmf->output);
        stmf->stm = to_stm_device(dev);
@@ -382,9 +384,10 @@ static int stm_char_open(struct inode *inode, struct file 
*file)
        return nonseekable_open(inode, file);
 
 err_free:
+       kfree(stmf);
+err_put_device:
        /* matches class_find_device() above */
        put_device(dev);
-       kfree(stmf);
 
        return err;
 }
-- 
2.7.3