From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (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 0E270474243 for ; Tue, 25 Aug 2026 13:21:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787664091; cv=none; b=GgijM+cTdZ3HRj0p/5kVrl3OdIo70JN/nDxf0sZaVXZnbn7nRlX0TFfXl79SRYZIMjHE92hW3k7UTQP6Y8sqdgRmcvbmR+s8Ur7dF6QjzZnL/+TCB8UE1CDOZ7dLk+yv6dyvRy5PJtGTPnlC93gyQIcdKylGQyCdNbdQ/Boh+x8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787664091; c=relaxed/simple; bh=FzRo1GPNzAWelnrKwWW+888gA+zU/UXIf9GDxf2VjrM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=gkRtPIEyUU2vrlArhyYgHRP2xfpR8Z9x/jDgjhWkhc1K66iMENNiSW5uon1/sLpSXiGg11Z7EQlqTHBWuQ4bBGhyhTLmcfieGJbRgpXoxZZ6tVmrbmjG1S6p1atlUQlbK5EVDvb66E3JmZo20aopnY8qgWcwgjShFdkJQoLUkno= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=dMTB0zP5; arc=none smtp.client-ip=170.10.133.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="dMTB0zP5" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1787664082; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=M/Qxd7N6jCXPKHznu5KtiQXyFK2J5SiupV4se6oGxR0=; b=dMTB0zP5Dc2Zf+iXWXwKAo8gQGjJVgTn0xLIJMZF7fYUkgiApQLJyrApEtKL7DlxImU2WC noUjd74HgKGprJksH+xBTPSoJ4UvQgdVCoug44hn7yw6IcBfSgya3XrUA8ntru+au+oVVD HTQK1UKAbXlXJPh2quLb68jzqnD3mY0= Received: from mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-638-VS0MFFZINZafYnIVEXtWbg-1; Tue, 25 Aug 2026 09:21:18 -0400 X-MC-Unique: VS0MFFZINZafYnIVEXtWbg-1 X-Mimecast-MFC-AGG-ID: VS0MFFZINZafYnIVEXtWbg_1787664077 Received: from mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.12]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 0DBAF1978F71; Tue, 25 Aug 2026 13:21:17 +0000 (UTC) Received: from warthog.com (unknown [10.44.32.15]) by mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 2ECAD1955F08; Tue, 25 Aug 2026 13:21:13 +0000 (UTC) From: David Howells To: Christian Brauner Cc: David Howells , Paulo Alcantara , netfs@lists.linux.dev, linux-afs@lists.infradead.org, linux-cifs@vger.kernel.org, ceph-devel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 5/9] netfs: Fix subreq ref leak Date: Tue, 25 Aug 2026 14:20:39 +0100 Message-ID: <20260825132045.1000787-6-dhowells@redhat.com> In-Reply-To: <20260825132045.1000787-1-dhowells@redhat.com> References: <20260825132045.1000787-1-dhowells@redhat.com> Precedence: bulk X-Mailing-List: ceph-devel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 3.0 on 10.30.177.12 Fix a subrequest ref leak in netfs_unbuffered_write() in the event that subreq->io_iter ends up zero length during preparation. Fixes: a0b4c7a49137e ("netfs: Fix unbuffered/DIO writes to dispatch subrequests in strict sequence") Link: https://sashiko.dev/#/patchset/20260824120224.504575-1-dhowells%40redhat.com Signed-off-by: David Howells cc: Paulo Alcantara cc: netfs@lists.linux.dev cc: linux-fsdevel@vger.kernel.org --- fs/netfs/direct_write.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/fs/netfs/direct_write.c b/fs/netfs/direct_write.c index f33ccddaa826..fbcfadb232ee 100644 --- a/fs/netfs/direct_write.c +++ b/fs/netfs/direct_write.c @@ -121,8 +121,14 @@ static int netfs_unbuffered_write(struct netfs_io_request *wreq) } iov_iter_truncate(&subreq->io_iter, wreq->len - wreq->transferred); - if (!iov_iter_count(&subreq->io_iter)) + if (!iov_iter_count(&subreq->io_iter)) { + pr_warn("netfs: Unexpected zero-length iterator R=%08x\n", + wreq->debug_id); + __set_bit(NETFS_SREQ_FAILED, &subreq->flags); + netfs_write_subrequest_terminated(subreq, -EIO); + wreq->error = -EIO; break; + } subreq->len = netfs_limit_iter(&subreq->io_iter, 0, stream->sreq_max_len,