1 files changed, 12 insertions, 7 deletions

diff --git a/fs/kernfs/file.c b/fs/kernfs/file.c
index 8034706a7af8..5e9a80cfc3d8 100644
--- a/fs/kernfs/file.c
+++ b/fs/kernfs/file.c
@@ -484,6 +484,8 @@ static int kernfs_fop_mmap(struct file *file, struct vm_area_struct *vma)
 
         ops = kernfs_ops(of->kn);
         rc = ops->mmap(of, vma);
+        if (rc)
+                goto out_put;
 
         /*
          * PowerPC's pci_mmap of legacy_mem uses shmem_zero_setup()
@@ -608,6 +610,7 @@ static void kernfs_put_open_node(struct kernfs_node *kn,
 static int kernfs_fop_open(struct inode *inode, struct file *file)
 {
         struct kernfs_node *kn = file->f_path.dentry->d_fsdata;
+        struct kernfs_root *root = kernfs_root(kn);
         const struct kernfs_ops *ops;
         struct kernfs_open_file *of;
         bool has_read, has_write, has_mmap;
@@ -622,14 +625,16 @@ static int kernfs_fop_open(struct inode *inode, struct file *file)
         has_write = ops->write || ops->mmap;
         has_mmap = ops->mmap;
 
-        /* check perms and supported operations */
-        if ((file->f_mode & FMODE_WRITE) &&
-            (!(inode->i_mode & S_IWUGO) || !has_write))
-                goto err_out;
+        /* see the flag definition for details */
+        if (root->flags & KERNFS_ROOT_EXTRA_OPEN_PERM_CHECK) {
+                if ((file->f_mode & FMODE_WRITE) &&
+                    (!(inode->i_mode & S_IWUGO) || !has_write))
+                        goto err_out;
 
-        if ((file->f_mode & FMODE_READ) &&
-            (!(inode->i_mode & S_IRUGO) || !has_read))
-                goto err_out;
+                if ((file->f_mode & FMODE_READ) &&
+                    (!(inode->i_mode & S_IRUGO) || !has_read))
+                        goto err_out;
+        }
 
         /* allocate a kernfs_open_file for the file */
         error = -ENOMEM;