Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 57f5a5a9 authored by Miklos Szeredi's avatar Miklos Szeredi Committed by Greg Kroah-Hartman
Browse files

UPSTREAM: ovl: simplify file splice 



commit 82a763e61e2b601309d696d4fa514c77d64ee1be upstream.

generic_file_splice_read() and iter_file_splice_write() will call back into
f_op->iter_read() and f_op->iter_write() respectively.  These already do
the real file lookup and cred override.  So the code in ovl_splice_read()
and ovl_splice_write() is redundant.

In addition the ovl_file_accessed() call in ovl_splice_write() is
incorrect, though probably harmless.

Fix by calling generic_file_splice_read() and iter_file_splice_write()
directly.

Bug: 203035944
Signed-off-by: default avatarMiklos Szeredi <mszeredi@redhat.com>
[reported to resolve issues with 1a980b8cbf00 ("ovl: add splice file read write helper")]
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Change-Id: I1b3c7610b27faad8eefa91dead167ceaeb4ff0d8
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@google.com>
parent 65d414cb

fs/overlayfs/file.c

+2 −44
Original line number Diff line number Diff line
@@ -296,48 +296,6 @@ static ssize_t ovl_write_iter(struct kiocb *iocb, struct iov_iter *iter) 
	return ret;

}



static ssize_t ovl_splice_read(struct file *in, loff_t *ppos,

			 struct pipe_inode_info *pipe, size_t len,

			 unsigned int flags)

{

	ssize_t ret;

	struct fd real;

	const struct cred *old_cred;



	ret = ovl_real_fdget(in, &real);

	if (ret)

		return ret;



	old_cred = ovl_override_creds(file_inode(in)->i_sb);

	ret = generic_file_splice_read(real.file, ppos, pipe, len, flags);

	revert_creds(old_cred);



	ovl_file_accessed(in);

	fdput(real);

	return ret;

}



static ssize_t

ovl_splice_write(struct pipe_inode_info *pipe, struct file *out,

			  loff_t *ppos, size_t len, unsigned int flags)

{

	struct fd real;

	const struct cred *old_cred;

	ssize_t ret;



	ret = ovl_real_fdget(out, &real);

	if (ret)

		return ret;



	old_cred = ovl_override_creds(file_inode(out)->i_sb);

	ret = iter_file_splice_write(pipe, real.file, ppos, len, flags);

	revert_creds(old_cred);



	ovl_file_accessed(out);

	fdput(real);

	return ret;

}



static int ovl_fsync(struct file *file, loff_t start, loff_t end, int datasync)

{

	struct fd real;
@@ -694,8 +652,8 @@ const struct file_operations ovl_file_operations = { 
	.fadvise	= ovl_fadvise,

	.unlocked_ioctl	= ovl_ioctl,

	.compat_ioctl	= ovl_compat_ioctl,

	.splice_read    = ovl_splice_read,

	.splice_write   = ovl_splice_write,

	.splice_read    = generic_file_splice_read,

	.splice_write   = iter_file_splice_write,



	.copy_file_range	= ovl_copy_file_range,

	.remap_file_range	= ovl_remap_file_range,