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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id EEBC0C49EC2 for ; Tue, 23 Aug 2022 12:03:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1359285AbiHWMDd (ORCPT ); Tue, 23 Aug 2022 08:03:33 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46126 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1359691AbiHWMCL (ORCPT ); Tue, 23 Aug 2022 08:02:11 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1396D97D71; Tue, 23 Aug 2022 02:36:17 -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 dfw.source.kernel.org (Postfix) with ESMTPS id 9523361469; Tue, 23 Aug 2022 09:35:19 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A0829C433D6; Tue, 23 Aug 2022 09:35:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1661247319; bh=JBtUajIUUTvXn1dwEIei/vptr1iv5ncaSZumZ5qjilw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=OUQTmBLW1lWTwQ6vzlAZlWaeEei7ohQkS+ju0vJpvdFhtseiljw5pKSg12n8IFOuH O3iOJhxWf1cPPJbprSh+ERpyyYhX+QZKdfqhJLU8wFJUA7fO8RODtJ17UCt1Jlm2bh 4ZreNoFrVmLOQKoADmgLRPwUudpnBRheT6U+1xik= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Oleksij Rempel , Fedor Pchelkin , Alexey Khoroshilov , Marc Kleine-Budde Subject: [PATCH 5.4 387/389] can: j1939: j1939_session_destroy(): fix memory leak of skbs Date: Tue, 23 Aug 2022 10:27:45 +0200 Message-Id: <20220823080131.742034120@linuxfoundation.org> X-Mailer: git-send-email 2.37.2 In-Reply-To: <20220823080115.331990024@linuxfoundation.org> References: <20220823080115.331990024@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Fedor Pchelkin commit 8c21c54a53ab21842f5050fa090f26b03c0313d6 upstream. We need to drop skb references taken in j1939_session_skb_queue() when destroying a session in j1939_session_destroy(). Otherwise those skbs would be lost. Link to Syzkaller info and repro: https://forge.ispras.ru/issues/11743. Found by Linux Verification Center (linuxtesting.org) with Syzkaller. V1: https://lore.kernel.org/all/20220708175949.539064-1-pchelkin@ispras.ru Fixes: 9d71dd0c7009 ("can: add support of SAE J1939 protocol") Suggested-by: Oleksij Rempel Signed-off-by: Fedor Pchelkin Signed-off-by: Alexey Khoroshilov Acked-by: Oleksij Rempel Link: https://lore.kernel.org/all/20220805150216.66313-1-pchelkin@ispras.ru Signed-off-by: Marc Kleine-Budde Signed-off-by: Greg Kroah-Hartman --- net/can/j1939/transport.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) --- a/net/can/j1939/transport.c +++ b/net/can/j1939/transport.c @@ -260,6 +260,8 @@ static void __j1939_session_drop(struct static void j1939_session_destroy(struct j1939_session *session) { + struct sk_buff *skb; + if (session->err) j1939_sk_errqueue(session, J1939_ERRQUEUE_ABORT); else @@ -270,7 +272,11 @@ static void j1939_session_destroy(struct WARN_ON_ONCE(!list_empty(&session->sk_session_queue_entry)); WARN_ON_ONCE(!list_empty(&session->active_session_list_entry)); - skb_queue_purge(&session->skb_queue); + while ((skb = skb_dequeue(&session->skb_queue)) != NULL) { + /* drop ref taken in j1939_session_skb_queue() */ + skb_unref(skb); + kfree_skb(skb); + } __j1939_session_drop(session); j1939_priv_put(session->priv); kfree(session);