Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull misc vfs updates from Al Viro:
 "Assorted misc bits and pieces.

  There are several single-topic branches left after this (rename2
  series from Miklos, current_time series from Deepa Dinamani, xattr
  series from Andreas, uaccess stuff from from me) and I'd prefer to
  send those separately"

* 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (39 commits)
  proc: switch auxv to use of __mem_open()
  hpfs: support FIEMAP
  cifs: get rid of unused arguments of CIFSSMBWrite()
  posix_acl: uapi header split
  posix_acl: xattr representation cleanups
  fs/aio.c: eliminate redundant loads in put_aio_ring_file
  fs/internal.h: add const to ns_dentry_operations declaration
  compat: remove compat_printk()
  fs/buffer.c: make __getblk_slow() static
  proc: unsigned file descriptors
  fs/file: more unsigned file descriptors
  fs: compat: remove redundant check of nr_segs
  cachefiles: Fix attempt to read i_blocks after deleting file [ver #2]
  cifs: don't use memcpy() to copy struct iov_iter
  get rid of separate multipage fault-in primitives
  fs: Avoid premature clearing of capabilities
  fs: Give dentry to inode_change_ok() instead of inode
  fuse: Propagate dentry down to inode_change_ok()
  ceph: Propagate dentry down to inode_change_ok()
  xfs: Propagate dentry down to inode_change_ok()
  ...

1 files changed, 14 insertions, 3 deletions

diff --git a/fs/open.c b/fs/open.c
index 4fd6e256f4f4..8aeb08bb278b 100644
--- 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;