From patchwork Fri Mar 25 15:04:49 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 554600 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7E41DC433F5 for ; Fri, 25 Mar 2022 15:09:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1376292AbiCYPLa (ORCPT ); Fri, 25 Mar 2022 11:11:30 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44610 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1359730AbiCYPLW (ORCPT ); Fri, 25 Mar 2022 11:11:22 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E720C5F256; Fri, 25 Mar 2022 08:08:34 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id A59A2B82901; Fri, 25 Mar 2022 15:08:33 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D1060C340E9; Fri, 25 Mar 2022 15:08:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1648220912; bh=KNwn+QBHBRBFD2JCHuCLDSoj/tzf/rXmQRsErk4L1h8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ThkWYQ/RDLzH1Q1tcPv8c3ic4qys7I0U0+XRfGhzDuHYlrTyca/lYtPRGb8w9O+Jk Oh7iAdJ9BSyqguN/fiLHWTKYrROs/WIw5Fd7XOBdE1MJZamgWTvswAO97xnkvsEyHj NsOLOXDT5pV3C9s7wOucWkBM7gOfmjiZIopjT3eE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Eric Dumazet , =?utf-8?b?6LW15a2Q6L2p?= , Stoyan Manolov , Jakub Kicinski Subject: [PATCH 5.4 09/29] llc: fix netdevice reference leaks in llc_ui_bind() Date: Fri, 25 Mar 2022 16:04:49 +0100 Message-Id: <20220325150418.855959068@linuxfoundation.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220325150418.585286754@linuxfoundation.org> References: <20220325150418.585286754@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Eric Dumazet commit 764f4eb6846f5475f1244767d24d25dd86528a4a upstream. Whenever llc_ui_bind() and/or llc_ui_autobind() took a reference on a netdevice but subsequently fail, they must properly release their reference or risk the infamous message from unregister_netdevice() at device dismantle. unregister_netdevice: waiting for eth0 to become free. Usage count = 3 Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet Reported-by: 赵子轩 Reported-by: Stoyan Manolov Link: https://lore.kernel.org/r/20220323004147.1990845-1-eric.dumazet@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman --- net/llc/af_llc.c | 8 ++++++++ 1 file changed, 8 insertions(+) --- a/net/llc/af_llc.c +++ b/net/llc/af_llc.c @@ -311,6 +311,10 @@ static int llc_ui_autobind(struct socket sock_reset_flag(sk, SOCK_ZAPPED); rc = 0; out: + if (rc) { + dev_put(llc->dev); + llc->dev = NULL; + } return rc; } @@ -409,6 +413,10 @@ static int llc_ui_bind(struct socket *so out_put: llc_sap_put(sap); out: + if (rc) { + dev_put(llc->dev); + llc->dev = NULL; + } release_sock(sk); return rc; }