Merge remote-tracking branch 'ovl/misc' into work.misc

[cascardo/linux.git] / fs / open.c

diff --git a/fs/open.c b/fs/open.c
index 4fd6e25..8aeb08b 100644 (file)
--- a/fs/open.c
+++ b/fs/open.c
@@ -68,6 +68,7 @@ int do_truncate(struct dentry *dentry, loff_t length, unsigned int time_attrs,
 long vfs_truncate(const struct path *path, loff_t length)
 {
        struct inode *inode;
+       struct dentry *upperdentry;
        long error;
 
        inode = path->dentry->d_inode;
@@ -90,7 +91,17 @@ long vfs_truncate(const struct path *path, loff_t length)
        if (IS_APPEND(inode))
                goto mnt_drop_write_and_out;
 
-       error = get_write_access(inode);
+       /*
+        * If this is an overlayfs then do as if opening the file so we get
+        * write access on the upper inode, not on the overlay inode.  For
+        * non-overlay filesystems d_real() is an identity function.
+        */
+       upperdentry = d_real(path->dentry, NULL, O_WRONLY);
+       error = PTR_ERR(upperdentry);
+       if (IS_ERR(upperdentry))
+               goto mnt_drop_write_and_out;
+
+       error = get_write_access(upperdentry->d_inode);
        if (error)
                goto mnt_drop_write_and_out;
 
@@ -109,7 +120,7 @@ long vfs_truncate(const struct path *path, loff_t length)
                error = do_truncate(path->dentry, length, 0, NULL);
 
 put_write_and_out:
-       put_write_access(inode);
+       put_write_access(upperdentry->d_inode);
 mnt_drop_write_and_out:
        mnt_drop_write(path->mnt);
 out:
@@ -726,7 +737,7 @@ static int do_dentry_open(struct file *f,
        if (error)
                goto cleanup_all;
 
-       error = break_lease(inode, f->f_flags);
+       error = break_lease(locks_inode(f), f->f_flags);
        if (error)
                goto cleanup_all;