On Sun, May 13, 2018 at 9:41 AM Mimi Zohar <zohar@xxxxxxxxxxxxxxxxxx> wrote:
> On Fri, 2018-05-11 at 16:12 -0700, Matthew Garrett wrote:
> +
> > + if (strcmp(xattr->name, ".") == 0) {
> > + evm_xattrs_locked = 1;
> > + inode = evm_xattrs->d_inode;
> > + inode_lock(inode);
> > + newattrs.ia_mode = S_IFREG | 0440;
> > + newattrs.ia_valid = ATTR_MODE;
> > + err = notify_change(evm_xattrs, &newattrs, NULL);
> > + inode_unlock(inode);
> > + audit_log_format(ab, "locked");
> > + if (!err)
> > + err = count;
> > + goto out;
> > + }
> > +
> > + audit_log_format(ab, "xattr=");
> > + audit_log_untrustedstring(ab, xattr->name);
> > +
> > + if (strncmp(xattr->name, XATTR_SECURITY_PREFIX,
> > + XATTR_SECURITY_PREFIX_LEN) != 0) {
> > + err = -EINVAL;
> > + goto out;
> > + }
> This test now prevents locking the xattr names list. Making this an
> else clause will fix it.
Are you sure? The check for "." happens before this, and jumps over the
rest of the function.
