From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from zeniv.linux.org.uk (zeniv.linux.org.uk [62.89.141.173]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 71769220F2D for ; Fri, 27 Feb 2026 15:19:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=62.89.141.173 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772205577; cv=none; b=Jbg2Km6bX3c0gDRlFa/8EcOAC3+qB5xbnTZKsUTrdUB2l61rj1Ail9giTFXGZjO0lH5XTCYrFlU5z92In26nVJ42Y8LSvxZgWH7YyvvDOem7h9OYP/anQfxZxEHHkaUju7LeCnUxukn7Tk/54gPyKVnQdfPPURkn+fJisj8zv/s= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772205577; c=relaxed/simple; bh=04FZaqkVEhg84Q1umwpvGK79aJfyhgFm3Bcy6v5nt7A=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=ujvC+kAY9QAWLutCCfe1aJfaPU5ZNMqNDfQDfj3A8YyqmktzgF/QJOmLiSnsgqJNviYXWZ7u5WRPsj9ZmT0GWlPBpT4H/aAOTQiXZiYxbTDGgRR4oTdsEfbNqEziPTX3Yi++aQ/UkwjpEkG7awwciAJ5vvqgxRUTuQ8ivJB9GrM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=zeniv.linux.org.uk; spf=none smtp.mailfrom=ftp.linux.org.uk; dkim=pass (2048-bit key) header.d=linux.org.uk header.i=@linux.org.uk header.b=XA/QaRea; arc=none smtp.client-ip=62.89.141.173 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=zeniv.linux.org.uk Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=ftp.linux.org.uk Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linux.org.uk header.i=@linux.org.uk header.b="XA/QaRea" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=linux.org.uk; s=zeniv-20220401; h=Sender:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=M+rMQQjpfREnEirMRx1pwCQH+CtMm8K++5IcPtNx06M=; b=XA/QaReaOg1VPXHDZKNFKEBUJP ZiNv7OegJsQ3TbeBPvQyNwPkoLvLe7gnDkIowV/7lJk5qVYQt5Z9D7hDejcqxvyKPcgmvclO3UPGs qVcGToKYpVUbv70l/HXSxaADc3kpQe3maGdQ/CE3frgHwdI4dY3xLFFqmNzZLtxPUTtgt2NlvKr7J ibdkQax4Tj3oEEZW6rAkR2zG1ysYuXmIuXizW5P0na6yJ+Dc1PcRs3fa684p0GKBXT2IvaELBizHL p6zGA/WFowpBVsshQUYKz7h7+uSvv95B1+YRZHrQzSVxaps4WPufei8MoWz3vS7a07C6DRIw/sA5G g7YGjRJg==; Received: from viro by zeniv.linux.org.uk with local (Exim 4.99.1 #2 (Red Hat Linux)) id 1vvzfP-00000008Meb-3k0S; Fri, 27 Feb 2026 15:22:12 +0000 Date: Fri, 27 Feb 2026 15:22:11 +0000 From: Al Viro To: "J. R. Okajima" Cc: linux-fsdevel@vger.kernel.org Subject: Re: v7.0-rc1, name_to_handle_at(..., AT_EMPTY_PATH) Message-ID: <20260227152211.GB3836593@ZenIV> References: <14544.1772189098@jrotkm2> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <14544.1772189098@jrotkm2> Sender: Al Viro On Fri, Feb 27, 2026 at 07:44:58PM +0900, J. R. Okajima wrote: > Hello Al Viro, > > By the commit in v7.0-rc1, > 154ef7dce6a4d 2026-01-16 name_to_handle_at(): use CLASS(filename_uflags) > name_to_handle_at(2) stopped handling AT_EMPTY_PATH, and an application > which issues > name_to_handle_at(fd, "", handle, &mnt_id, AT_EMPTY_PATH); > started failing. > > It is due to the commit dropped setting LOOKUP_EMPTY to lookup_flags in > name_to_handle_at(2). Huh? CLASS(filename_uflags, filename)(name, flag); *does* accept empty path if flag & AT_EMPTY_PATH is non-zero. So if you are really observing such failures, something else must've gone wrong. Details, please. This struct filename *getname_uflags(const char __user *filename, int uflags) { int flags = (uflags & AT_EMPTY_PATH) ? LOOKUP_EMPTY : 0; return getname_flags(filename, flags); } is where AT_EMPTY_PATH is handled; could you check the arguuments it's getting in your reproducer and argument passed to getname_flags()?