From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3A6FAECDE46 for ; Thu, 25 Oct 2018 14:10:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 008972054F for ; Thu, 25 Oct 2018 14:10:54 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="ET3v4Dfv" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 008972054F Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727756AbeJYWns (ORCPT ); Thu, 25 Oct 2018 18:43:48 -0400 Received: from mail.kernel.org ([198.145.29.99]:52170 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727699AbeJYWnh (ORCPT ); Thu, 25 Oct 2018 18:43:37 -0400 Received: from sasha-vm.mshome.net (unknown [167.98.65.38]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id AD52920848; Thu, 25 Oct 2018 14:10:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1540476642; bh=l6mP9jJgyseYTWZ+SV/QD9/p7wZ9QMHdNbfROInuc34=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ET3v4DfvcUZFuKXyjCnWFGN+XIhYQSxQrXkcENtt2t4dFC7JdFfzLw+SIZRWNGuWP n4RcBPjA5NhhTqL7lc3Y7wjNVv8I7fFStTC4axHdd2F0KoNFzHkBeP5n0sercNi64T 9RJJpFsbBFjKfe8rtrHiW/CdVNd3k4rmLjrDbMWg= From: Sasha Levin To: stable@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Doron Roberts-Kedes , "David S . Miller" , Sasha Levin Subject: [PATCH AUTOSEL 4.18 7/8] tls: Fix improper revert in zerocopy_from_iter Date: Thu, 25 Oct 2018 10:10:28 -0400 Message-Id: <20181025141029.213274-7-sashal@kernel.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20181025141029.213274-1-sashal@kernel.org> References: <20181025141029.213274-1-sashal@kernel.org> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Doron Roberts-Kedes [ Upstream commit 2da19ed3e4a87db16c0f69039da9f17a9596c350 ] The current code is problematic because the iov_iter is reverted and never advanced in the non-error case. This patch skips the revert in the non-error case. This patch also fixes the amount by which the iov_iter is reverted. Currently, iov_iter is reverted by size, which can be greater than the amount by which the iter was actually advanced. Instead, only revert by the amount that the iter was advanced. Fixes: 4718799817c5 ("tls: Fix zerocopy_from_iter iov handling") Signed-off-by: Doron Roberts-Kedes Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- net/tls/tls_sw.c | 12 +++++------- 1 file changed, 5 insertions(+), 7 deletions(-) diff --git a/net/tls/tls_sw.c b/net/tls/tls_sw.c index 9fab8e5a4a5b..994ddc7ec9b1 100644 --- a/net/tls/tls_sw.c +++ b/net/tls/tls_sw.c @@ -286,7 +286,7 @@ static int zerocopy_from_iter(struct sock *sk, struct iov_iter *from, int length, int *pages_used, unsigned int *size_used, struct scatterlist *to, int to_max_pages, - bool charge, bool revert) + bool charge) { struct page *pages[MAX_SKB_FRAGS]; @@ -335,10 +335,10 @@ static int zerocopy_from_iter(struct sock *sk, struct iov_iter *from, } out: + if (rc) + iov_iter_revert(from, size - *size_used); *size_used = size; *pages_used = num_elem; - if (revert) - iov_iter_revert(from, size); return rc; } @@ -440,7 +440,7 @@ int tls_sw_sendmsg(struct sock *sk, struct msghdr *msg, size_t size) &ctx->sg_plaintext_size, ctx->sg_plaintext_data, ARRAY_SIZE(ctx->sg_plaintext_data), - true, false); + true); if (ret) goto fallback_to_reg_send; @@ -453,8 +453,6 @@ int tls_sw_sendmsg(struct sock *sk, struct msghdr *msg, size_t size) copied -= try_to_copy; fallback_to_reg_send: - iov_iter_revert(&msg->msg_iter, - ctx->sg_plaintext_size - orig_size); trim_sg(sk, ctx->sg_plaintext_data, &ctx->sg_plaintext_num_elem, &ctx->sg_plaintext_size, @@ -828,7 +826,7 @@ int tls_sw_recvmsg(struct sock *sk, err = zerocopy_from_iter(sk, &msg->msg_iter, to_copy, &pages, &chunk, &sgin[1], - MAX_SKB_FRAGS, false, true); + MAX_SKB_FRAGS, false); if (err < 0) goto fallback_to_reg_recv; -- 2.17.1