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,DKIMWL_WL_HIGH, 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=unavailable 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 18340C43603 for ; Fri, 5 Mar 2021 12:24:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EF8CE6502D for ; Fri, 5 Mar 2021 12:24:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229960AbhCEMXm (ORCPT ); Fri, 5 Mar 2021 07:23:42 -0500 Received: from mail.kernel.org ([198.145.29.99]:58180 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229558AbhCEMXU (ORCPT ); Fri, 5 Mar 2021 07:23:20 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 6DDA064FEE; Fri, 5 Mar 2021 12:23:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1614946999; bh=5aDedKZVvSe29sFYJ9x/T5C67ZydrxkJ9kxIEJU1DkY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=YHzjNHl/wQlvVT/9Xi1H3lf0+wIr1qKUexvIrdfqLpV1Y9ECoiFTw1eyEkkEgypWt pbaKjdv8f8wCt1v64Ya4clm0shfIs3jaPKobE2yc/KakuwjOEqHT3+v0vKEvs07fQY 9bCct3Fw99BX/nTEuMMAQQQu5sLj7Ov5CPBzHMRY= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Alexander Egorenkov , Julian Wiedmann , Willem de Bruijn , Jakub Kicinski Subject: [PATCH 5.11 012/104] net/af_iucv: remove WARN_ONCE on malformed RX packets Date: Fri, 5 Mar 2021 13:20:17 +0100 Message-Id: <20210305120903.784327098@linuxfoundation.org> X-Mailer: git-send-email 2.30.1 In-Reply-To: <20210305120903.166929741@linuxfoundation.org> References: <20210305120903.166929741@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: Alexander Egorenkov commit 27e9c1de529919d8dd7d072415d3bcae77709300 upstream. syzbot reported the following finding: AF_IUCV failed to receive skb, len=0 WARNING: CPU: 0 PID: 522 at net/iucv/af_iucv.c:2039 afiucv_hs_rcv+0x174/0x190 net/iucv/af_iucv.c:2039 CPU: 0 PID: 522 Comm: syz-executor091 Not tainted 5.10.0-rc1-syzkaller-07082-g55027a88ec9f #0 Hardware name: IBM 3906 M04 701 (KVM/Linux) Call Trace: [<00000000b87ea538>] afiucv_hs_rcv+0x178/0x190 net/iucv/af_iucv.c:2039 ([<00000000b87ea534>] afiucv_hs_rcv+0x174/0x190 net/iucv/af_iucv.c:2039) [<00000000b796533e>] __netif_receive_skb_one_core+0x13e/0x188 net/core/dev.c:5315 [<00000000b79653ce>] __netif_receive_skb+0x46/0x1c0 net/core/dev.c:5429 [<00000000b79655fe>] netif_receive_skb_internal+0xb6/0x220 net/core/dev.c:5534 [<00000000b796ac3a>] netif_receive_skb+0x42/0x318 net/core/dev.c:5593 [<00000000b6fd45f4>] tun_rx_batched.isra.0+0x6fc/0x860 drivers/net/tun.c:1485 [<00000000b6fddc4e>] tun_get_user+0x1c26/0x27f0 drivers/net/tun.c:1939 [<00000000b6fe0f00>] tun_chr_write_iter+0x158/0x248 drivers/net/tun.c:1968 [<00000000b4f22bfa>] call_write_iter include/linux/fs.h:1887 [inline] [<00000000b4f22bfa>] new_sync_write+0x442/0x648 fs/read_write.c:518 [<00000000b4f238fe>] vfs_write.part.0+0x36e/0x5d8 fs/read_write.c:605 [<00000000b4f2984e>] vfs_write+0x10e/0x148 fs/read_write.c:615 [<00000000b4f29d0e>] ksys_write+0x166/0x290 fs/read_write.c:658 [<00000000b8dc4ab4>] system_call+0xe0/0x28c arch/s390/kernel/entry.S:415 Last Breaking-Event-Address: [<00000000b8dc64d4>] __s390_indirect_jump_r14+0x0/0xc Malformed RX packets shouldn't generate any warnings because debugging info already flows to dropmon via the kfree_skb(). Signed-off-by: Alexander Egorenkov Reviewed-by: Julian Wiedmann Signed-off-by: Julian Wiedmann Acked-by: Willem de Bruijn Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman --- net/iucv/af_iucv.c | 1 - 1 file changed, 1 deletion(-) --- a/net/iucv/af_iucv.c +++ b/net/iucv/af_iucv.c @@ -2036,7 +2036,6 @@ static int afiucv_hs_rcv(struct sk_buff char nullstring[8]; if (!pskb_may_pull(skb, sizeof(*trans_hdr))) { - WARN_ONCE(1, "AF_IUCV failed to receive skb, len=%u", skb->len); kfree_skb(skb); return NET_RX_SUCCESS; }