ovl_setattr() can be passed an attr which has ATTR_FILE set and attr->ia_file is a file pointer to overlay file. This is done in open(O_TRUNC) path.
We should either replace with attr->ia_file with underlying file object or clear ATTR_FILE so that underlying filesystem does not end up using overlayfs file object pointer. There are no good use cases yet so for now clear ATTR_FILE. fuse seems to be one user which can use this. But it can work even without this. So it is not mandatory to pass ATTR_FILE to fuse. Signed-off-by: Vivek Goyal <[email protected]> --- fs/overlayfs/inode.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c index b0d42ece4d7c..8d147bc70f0b 100644 --- a/fs/overlayfs/inode.c +++ b/fs/overlayfs/inode.c @@ -58,6 +58,11 @@ int ovl_setattr(struct dentry *dentry, struct iattr *attr) if (attr->ia_valid & (ATTR_KILL_SUID|ATTR_KILL_SGID)) attr->ia_valid &= ~ATTR_MODE; + /* We might have to translate ovl file into underlying file + * object once some use cases are there. For now, simply + * don't let underlying filesystem rely on attr->ia_file */ + attr->ia_valid &= ~ATTR_FILE; + inode_lock(upperdentry->d_inode); old_cred = ovl_override_creds(dentry->d_sb); err = notify_change(upperdentry, attr, NULL); -- 2.25.3 _______________________________________________ Virtio-fs mailing list [email protected] https://www.redhat.com/mailman/listinfo/virtio-fs
