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=-18.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,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 284F6C433E0 for ; Mon, 11 Jan 2021 13:11:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D357922B51 for ; Mon, 11 Jan 2021 13:10:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731193AbhAKNKg (ORCPT ); Mon, 11 Jan 2021 08:10:36 -0500 Received: from mail.kernel.org ([198.145.29.99]:56990 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730922AbhAKNJj (ORCPT ); Mon, 11 Jan 2021 08:09:39 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id CA4A222D2C; Mon, 11 Jan 2021 13:08:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1610370539; bh=2oF1xm8tCBpOayJ3t4YzHCy8Kx1yxxEBHrgYOTGnDiY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=2qYyI5QK98vykrC9OLJIKt328/jf/vMfcBBM/wDZVPo86jVpgEVA4aeYG4nKdI7Ca BG8zR2wuLgCugCSyZ+g1DvZt4/V2vL5uUDiXH4XlVOWmAdBYx6pqorKj3F4NsZN4KI J5l0+nakrsXEq7wdzPEYU6MoeIqpnFA78erACDNU= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Yunjian Wang , Willem de Bruijn , Jason Wang , "Michael S. Tsirkin" , Jakub Kicinski Subject: [PATCH 4.19 26/77] tun: fix return value when the number of iovs exceeds MAX_SKB_FRAGS Date: Mon, 11 Jan 2021 14:01:35 +0100 Message-Id: <20210111130037.667158711@linuxfoundation.org> X-Mailer: git-send-email 2.30.0 In-Reply-To: <20210111130036.414620026@linuxfoundation.org> References: <20210111130036.414620026@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Yunjian Wang [ Upstream commit 950271d7cc0b4546af3549d8143c4132d6e1f138 ] Currently the tun_napi_alloc_frags() function returns -ENOMEM when the number of iovs exceeds MAX_SKB_FRAGS + 1. However this is inappropriate, we should use -EMSGSIZE instead of -ENOMEM. The following distinctions are matters: 1. the caller need to drop the bad packet when -EMSGSIZE is returned, which means meeting a persistent failure. 2. the caller can try again when -ENOMEM is returned, which means meeting a transient failure. Fixes: 90e33d459407 ("tun: enable napi_gro_frags() for TUN/TAP driver") Signed-off-by: Yunjian Wang Acked-by: Willem de Bruijn Acked-by: Jason Wang Acked-by: Michael S. Tsirkin Link: https://lore.kernel.org/r/1608864736-24332-1-git-send-email-wangyunjian@huawei.com Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman --- drivers/net/tun.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -1450,7 +1450,7 @@ static struct sk_buff *tun_napi_alloc_fr int i; if (it->nr_segs > MAX_SKB_FRAGS + 1) - return ERR_PTR(-ENOMEM); + return ERR_PTR(-EMSGSIZE); local_bh_disable(); skb = napi_get_frags(&tfile->napi);