Commit ba080305 authored by David Howells's avatar David Howells Committed by Steve French
Browse files

smb3: missing inode locks in punch hole 



smb3 fallocate punch hole was not grabbing the inode or filemap_invalidate
locks so could have race with pagemap reinstantiating the page.

Cc: stable@vger.kernel.org
Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
Signed-off-by: default avatarSteve French <stfrench@microsoft.com>
parent c919c164

fs/cifs/smb2ops.c

+6 −6
Original line number Diff line number Diff line
@@ -3384,7 +3384,7 @@ static long smb3_zero_range(struct file *file, struct cifs_tcon *tcon, 
static long smb3_punch_hole(struct file *file, struct cifs_tcon *tcon,

			    loff_t offset, loff_t len)

{

	struct inode *inode;

	struct inode *inode = file_inode(file);

	struct cifsFileInfo *cfile = file->private_data;

	struct file_zero_data_information fsctl_buf;

	long rc;
@@ -3393,14 +3393,12 @@ static long smb3_punch_hole(struct file *file, struct cifs_tcon *tcon, 


	xid = get_xid();



	inode = d_inode(cfile->dentry);



	inode_lock(inode);

	/* Need to make file sparse, if not already, before freeing range. */

	/* Consider adding equivalent for compressed since it could also work */

	if (!smb2_set_sparse(xid, tcon, cfile, inode, set_sparse)) {

		rc = -EOPNOTSUPP;

		free_xid(xid);

		return rc;

		goto out;

	}



	filemap_invalidate_lock(inode->i_mapping);
@@ -3420,8 +3418,10 @@ static long smb3_punch_hole(struct file *file, struct cifs_tcon *tcon, 
			(char *)&fsctl_buf,

			sizeof(struct file_zero_data_information),

			CIFSMaxBufSize, NULL, NULL);

	free_xid(xid);

	filemap_invalidate_unlock(inode->i_mapping);

out:

	inode_unlock(inode);

	free_xid(xid);

	return rc;

}