[PATCH] ovl: inode reference leak in ovl_is_inuse true case.

[youngjun]

When "ovl_is_inuse" true case, trap inode reference not put.
plus adding the comment explaining sequence of
ovl_is_inuse after ovl_setup_trap.

Signed-off-by: youngjun <her0gyu...@gmail.com>
---
 fs/overlayfs/super.c | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c
index 91476bc422f9..0396793dadb8 100644
--- a/fs/overlayfs/super.c
+++ b/fs/overlayfs/super.c
@@ -1029,6 +1029,12 @@ static const struct xattr_handler *ovl_xattr_handlers[] 
= {
        NULL
 };
 
+/*
+ * Check if lower root conflicts with this overlay layers before checking
+ * if it is in-use as upperdir/workdir of "another" mount, because we do
+ * not bother to check in ovl_is_inuse() if the upperdir/workdir is in fact
+ * in-use by our upperdir/workdir.
+ */
 static int ovl_setup_trap(struct super_block *sb, struct dentry *dir,
                          struct inode **ptrap, const char *name)
 {
@@ -1499,8 +1505,10 @@ static int ovl_get_layers(struct super_block *sb, struct 
ovl_fs *ofs,
 
                if (ovl_is_inuse(stack[i].dentry)) {
                        err = ovl_report_in_use(ofs, "lowerdir");
-                       if (err)
+                       if (err) {
+                               iput(trap);
                                goto out;
+                       }
                }
 
                mnt = clone_private_mount(&stack[i]);
-- 
2.17.1

Thank you for comment Amir. I modified patch as you said.