Merge branch 'miklos.fileattr' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull fileattr conversion updates from Miklos Szeredi via Al Viro:
 "This splits the handling of FS_IOC_[GS]ETFLAGS from ->ioctl() into a
  separate method.

  The interface is reasonably uniform across the filesystems that
  support it and gives nice boilerplate removal"

* 'miklos.fileattr' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (23 commits)
  ovl: remove unneeded ioctls
  fuse: convert to fileattr
  fuse: add internal open/release helpers
  fuse: unsigned open flags
  fuse: move ioctl to separate source file
  vfs: remove unused ioctl helpers
  ubifs: convert to fileattr
  reiserfs: convert to fileattr
  ocfs2: convert to fileattr
  nilfs2: convert to fileattr
  jfs: convert to fileattr
  hfsplus: convert to fileattr
  efivars: convert to fileattr
  xfs: convert to fileattr
  orangefs: convert to fileattr
  gfs2: convert to fileattr
  f2fs: convert to fileattr
  ext4: convert to fileattr
  ext2: convert to fileattr
  btrfs: convert to fileattr
  ...

5 files changed, 82 insertions, 116 deletions

diff --git a/fs/overlayfs/dir.c b/fs/overlayfs/dir.c
index 836f14b9d3a6..93efe7048a77 100644
--- a/fs/overlayfs/dir.c
+++ b/fs/overlayfs/dir.c
@@ -1301,4 +1301,6 @@ const struct inode_operations ovl_dir_inode_operations = {
 	.listxattr	= ovl_listxattr,
 	.get_acl	= ovl_get_acl,
 	.update_time	= ovl_update_time,
+	.fileattr_get	= ovl_fileattr_get,
+	.fileattr_set	= ovl_fileattr_set,
 };
diff --git a/fs/overlayfs/file.c b/fs/overlayfs/file.c
index 3847cdc069b5..c144183a7e09 100644
--- a/fs/overlayfs/file.c
+++ b/fs/overlayfs/file.c
@@ -482,112 +482,6 @@ static int ovl_fadvise(struct file *file, loff_t offset, loff_t len, int advice)
 	return ret;
 }
 
-static long ovl_real_ioctl(struct file *file, unsigned int cmd,
-			   unsigned long arg)
-{
-	struct fd real;
-	long ret;
-
-	ret = ovl_real_fdget(file, &real);
-	if (ret)
-		return ret;
-
-	ret = security_file_ioctl(real.file, cmd, arg);
-	if (!ret) {
-		/*
-		 * Don't override creds, since we currently can't safely check
-		 * permissions before doing so.
-		 */
-		ret = vfs_ioctl(real.file, cmd, arg);
-	}
-
-	fdput(real);
-
-	return ret;
-}
-
-static long ovl_ioctl_set_flags(struct file *file, unsigned int cmd,
-				unsigned long arg)
-{
-	long ret;
-	struct inode *inode = file_inode(file);
-
-	if (!inode_owner_or_capable(&init_user_ns, inode))
-		return -EACCES;
-
-	ret = mnt_want_write_file(file);
-	if (ret)
-		return ret;
-
-	inode_lock(inode);
-
-	/*
-	 * Prevent copy up if immutable and has no CAP_LINUX_IMMUTABLE
-	 * capability.
-	 */
-	ret = -EPERM;
-	if (!ovl_has_upperdata(inode) && IS_IMMUTABLE(inode) &&
-	    !capable(CAP_LINUX_IMMUTABLE))
-		goto unlock;
-
-	ret = ovl_maybe_copy_up(file_dentry(file), O_WRONLY);
-	if (ret)
-		goto unlock;
-
-	ret = ovl_real_ioctl(file, cmd, arg);
-
-	ovl_copyflags(ovl_inode_real(inode), inode);
-unlock:
-	inode_unlock(inode);
-
-	mnt_drop_write_file(file);
-
-	return ret;
-
-}
-
-long ovl_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
-{
-	long ret;
-
-	switch (cmd) {
-	case FS_IOC_GETFLAGS:
-	case FS_IOC_FSGETXATTR:
-		ret = ovl_real_ioctl(file, cmd, arg);
-		break;
-
-	case FS_IOC_FSSETXATTR:
-	case FS_IOC_SETFLAGS:
-		ret = ovl_ioctl_set_flags(file, cmd, arg);
-		break;
-
-	default:
-		ret = -ENOTTY;
-	}
-
-	return ret;
-}
-
-#ifdef CONFIG_COMPAT
-long ovl_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
-{
-	switch (cmd) {
-	case FS_IOC32_GETFLAGS:
-		cmd = FS_IOC_GETFLAGS;
-		break;
-
-	case FS_IOC32_SETFLAGS:
-		cmd = FS_IOC_SETFLAGS;
-		break;
-
-	default:
-		return -ENOIOCTLCMD;
-	}
-
-	return ovl_ioctl(file, cmd, arg);
-}
-#endif
-
 enum ovl_copyop {
 	OVL_COPY,
 	OVL_CLONE,
@@ -687,10 +581,6 @@ const struct file_operations ovl_file_operations = {
 	.mmap		= ovl_mmap,
 	.fallocate	= ovl_fallocate,
 	.fadvise	= ovl_fadvise,
-	.unlocked_ioctl	= ovl_ioctl,
-#ifdef CONFIG_COMPAT
-	.compat_ioctl	= ovl_compat_ioctl,
-#endif
 	.splice_read    = generic_file_splice_read,
 	.splice_write   = iter_file_splice_write,
 
diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c
index 003cf83bf78a..c3c96b4b3b33 100644
--- a/fs/overlayfs/inode.c
+++ b/fs/overlayfs/inode.c
@@ -11,6 +11,8 @@
 #include <linux/posix_acl.h>
 #include <linux/ratelimit.h>
 #include <linux/fiemap.h>
+#include <linux/fileattr.h>
+#include <linux/security.h>
 #include "overlayfs.h"
 
 
@@ -500,6 +502,79 @@ static int ovl_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
 	return err;
 }
 
+/*
+ * Work around the fact that security_file_ioctl() takes a file argument.
+ * Introducing security_inode_fileattr_get/set() hooks would solve this issue
+ * properly.
+ */
+static int ovl_security_fileattr(struct dentry *dentry, struct fileattr *fa,
+				 bool set)
+{
+	struct path realpath;
+	struct file *file;
+	unsigned int cmd;
+	int err;
+
+	ovl_path_real(dentry, &realpath);
+	file = dentry_open(&realpath, O_RDONLY, current_cred());
+	if (IS_ERR(file))
+		return PTR_ERR(file);
+
+	if (set)
+		cmd = fa->fsx_valid ? FS_IOC_FSSETXATTR : FS_IOC_SETFLAGS;
+	else
+		cmd = fa->fsx_valid ? FS_IOC_FSGETXATTR : FS_IOC_GETFLAGS;
+
+	err = security_file_ioctl(file, cmd, 0);
+	fput(file);
+
+	return err;
+}
+
+int ovl_fileattr_set(struct user_namespace *mnt_userns,
+		     struct dentry *dentry, struct fileattr *fa)
+{
+	struct inode *inode = d_inode(dentry);
+	struct dentry *upperdentry;
+	const struct cred *old_cred;
+	int err;
+
+	err = ovl_want_write(dentry);
+	if (err)
+		goto out;
+
+	err = ovl_copy_up(dentry);
+	if (!err) {
+		upperdentry = ovl_dentry_upper(dentry);
+
+		old_cred = ovl_override_creds(inode->i_sb);
+		err = ovl_security_fileattr(dentry, fa, true);
+		if (!err)
+			err = vfs_fileattr_set(&init_user_ns, upperdentry, fa);
+		revert_creds(old_cred);
+		ovl_copyflags(ovl_inode_real(inode), inode);
+	}
+	ovl_drop_write(dentry);
+out:
+	return err;
+}
+
+int ovl_fileattr_get(struct dentry *dentry, struct fileattr *fa)
+{
+	struct inode *inode = d_inode(dentry);
+	struct dentry *realdentry = ovl_dentry_real(dentry);
+	const struct cred *old_cred;
+	int err;
+
+	old_cred = ovl_override_creds(inode->i_sb);
+	err = ovl_security_fileattr(dentry, fa, false);
+	if (!err)
+		err = vfs_fileattr_get(realdentry, fa);
+	revert_creds(old_cred);
+
+	return err;
+}
+
 static const struct inode_operations ovl_file_inode_operations = {
 	.setattr	= ovl_setattr,
 	.permission	= ovl_permission,
@@ -508,6 +583,8 @@ static const struct inode_operations ovl_file_inode_operations = {
 	.get_acl	= ovl_get_acl,
 	.update_time	= ovl_update_time,
 	.fiemap		= ovl_fiemap,
+	.fileattr_get	= ovl_fileattr_get,
+	.fileattr_set	= ovl_fileattr_set,
 };
 
 static const struct inode_operations ovl_symlink_inode_operations = {
diff --git a/fs/overlayfs/overlayfs.h b/fs/overlayfs/overlayfs.h
index 95cff83786a5..f38cb5e07eff 100644
--- a/fs/overlayfs/overlayfs.h
+++ b/fs/overlayfs/overlayfs.h
@@ -519,8 +519,9 @@ struct dentry *ovl_create_temp(struct dentry *workdir, struct ovl_cattr *attr);
 extern const struct file_operations ovl_file_operations;
 int __init ovl_aio_request_cache_init(void);
 void ovl_aio_request_cache_destroy(void);
-long ovl_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
-long ovl_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
+int ovl_fileattr_get(struct dentry *dentry, struct fileattr *fa);
+int ovl_fileattr_set(struct user_namespace *mnt_userns,
+		     struct dentry *dentry, struct fileattr *fa);
 
 /* copy_up.c */
 int ovl_copy_up(struct dentry *dentry);
diff --git a/fs/overlayfs/readdir.c b/fs/overlayfs/readdir.c
index f404a78e6b60..1ddad0967255 100644
--- a/fs/overlayfs/readdir.c
+++ b/fs/overlayfs/readdir.c
@@ -963,10 +963,6 @@ const struct file_operations ovl_dir_operations = {
 	.llseek		= ovl_dir_llseek,
 	.fsync		= ovl_dir_fsync,
 	.release	= ovl_dir_release,
-	.unlocked_ioctl	= ovl_ioctl,
-#ifdef CONFIG_COMPAT
-	.compat_ioctl	= ovl_compat_ioctl,
-#endif
 };
 
 int ovl_check_empty_dir(struct dentry *dentry, struct list_head *list)