From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 3705451EDFB; Thu, 17 Sep 2026 17:14:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789665265; cv=none; b=rlpV7yYkgvT4zUP5NSlZU8faqB8sE4EBRiG62yp8okSx5R1fF/jZ1IX6ECBAst6THFwWAnszKn4UZlMCyPteLb4cJJ9XBMJh3J7jdDAPd7A6SZIyPeAaRL37zYJojzyVVKSbywsXcw1G0ufVUMD52IbiN3C8Wp6Hti3v5B3oXEs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789665265; c=relaxed/simple; bh=8snMS1MT7fQr2TVPtodsxd4hCqcTmp1AU7V512WRkD4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=lSYqlSiEzYX1xlMZZWvgX99zJR3sLjlEP8bJzGsfOUvcEtQGtlLaABfXAUT7PdG3O/mUkAEAhPtEJDMDU8Xq3D/hJjyPTlXsCiPk4t38UdIm1tekNuBS82vu4rNHcFvTD+ePy3SVM8um/NEi9NOaPcB8fpGxNDVzdai/uCgR40c= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=p+qvKrFZ; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="p+qvKrFZ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1A1CC1F000FF; Thu, 17 Sep 2026 17:14:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789665263; bh=4VjqMsnc7nwQ8nTx/5JEGGY3+zp75uRX3TRZMVMj2Ok=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=p+qvKrFZKLBXvjzfngGsgezQ2UrZ992u83IJdmRyBopKYNqYeRPMPSHVfQ64N5CpZ hgeTxAzg11QAWn5PF/QLlt0UAnAx64Rw1YFGTofMOtOQRQs3lCFQPOnJVqeHHWgWmP qsXAzmT+bQhCF58o6nZswBNjs9p1ZgXmcoDlLKEI= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, David Howells , Paulo Alcantara , netfs@lists.linux.dev, linux-fsdevel@vger.kernel.org, "Christian Brauner (Amutable)" , Sasha Levin Subject: [PATCH 6.18 0645/1250] netfs: Fix subreq ref leak Date: Thu, 17 Sep 2026 16:07:20 +0100 Message-ID: <20260917151609.378491839@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260917151551.901433442@linuxfoundation.org> References: <20260917151551.901433442@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: netfs@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: David Howells [ Upstream commit 3c30087e27598d9d359763e8be9bd3017fe08348 ] 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 Link: https://patch.msgid.link/20260827134304.2075713-6-dhowells@redhat.com Acked-by: Paulo Alcantara cc: Paulo Alcantara cc: netfs@lists.linux.dev cc: linux-fsdevel@vger.kernel.org Signed-off-by: Christian Brauner (Amutable) Signed-off-by: Sasha Levin --- 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 6cba5bd60361d..abc8f6955fd50 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, -- 2.53.0