From patchwork Sat Jun 13 12:39:25 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Xiyu Yang X-Patchwork-Id: 1308655 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming-netdev@ozlabs.org Delivered-To: patchwork-incoming-netdev@ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=reject dis=none) header.from=fudan.edu.cn Authentication-Results: ozlabs.org; dkim=fail reason="key not found in DNS" header.d=fudan.edu.cn header.i=@fudan.edu.cn header.a=rsa-sha256 header.s=dkim header.b=rSW77YMq; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 49kcck5T6pz9sRK for ; Sat, 13 Jun 2020 22:40:06 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726362AbgFMMkD (ORCPT ); Sat, 13 Jun 2020 08:40:03 -0400 Received: from mail.fudan.edu.cn ([202.120.224.10]:48450 "EHLO fudan.edu.cn" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726039AbgFMMkC (ORCPT ); Sat, 13 Jun 2020 08:40:02 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fudan.edu.cn; s=dkim; h=Received:From:To:Cc:Subject:Date: Message-Id; bh=orDLlwUq6Gl4ZFuFaDVaEW2IqJ0LD91Me5OLf+FAEC8=; b=r SW77YMq1loIYxFCKZrwu7yfjfPaheZB55hkoXsNqd9NXG7VT/zSdtiVPyU7YivR6 hzhO20HHLN6L8bBMctIQKjA32e7BskSN+SSsSl3GEWI0tJ9H0ZZjPM8OJrZw/hcp wAkpYDMolQPmfPs/R1PNe8Qhs99IZVVSZCfJ7EnUdQ= Received: from localhost.localdomain (unknown [120.229.255.202]) by app1 (Coremail) with SMTP id XAUFCgDn7zMWyeReX8EYAA--.20920S3; Sat, 13 Jun 2020 20:39:52 +0800 (CST) From: Xiyu Yang To: Vlad Yasevich , Neil Horman , Marcelo Ricardo Leitner , "David S. Miller" , Jakub Kicinski , linux-sctp@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Cc: yuanxzhang@fudan.edu.cn, kjlu@umn.edu, Xiyu Yang , Xin Tan Subject: [PATCH] sctp: Fix sk_buff leak when receiving a datagram Date: Sat, 13 Jun 2020 20:39:25 +0800 Message-Id: <1592051965-94731-1-git-send-email-xiyuyang19@fudan.edu.cn> X-Mailer: git-send-email 2.7.4 X-CM-TRANSID: XAUFCgDn7zMWyeReX8EYAA--.20920S3 X-Coremail-Antispam: 1UD129KBjvdXoW7Wr43KF1fXrWxJw43Xr4xJFb_yoWDZFg_Ja 97CF1xX39ruFsa9aySkrs8AFZakanFqrWIgrsrK39rG345KF9rtrZ8KFZ3CryxWrWxZry5 JFn5Krnxu39xZjkaLaAFLSUrUUUUUb8apTn2vfkv8UJUUUU8Yxn0WfASr-VFAUDa7-sFnT 9fnUUIcSsGvfJTRUUUbfxFF20E14v26r4j6ryUM7CY07I20VC2zVCF04k26cxKx2IYs7xG 6rWj6s0DM7CIcVAFz4kK6r1j6r18M28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48ve4kI8w A2z4x0Y4vE2Ix0cI8IcVAFwI0_tr0E3s1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI0_Cr1j 6rxdM28EF7xvwVC2z280aVAFwI0_GcCE3s1l84ACjcxK6I8E87Iv6xkF7I0E14v26rxl6s 0DM2vYz4IE04k24VAvwVAKI4IrM2AIxVAIcxkEcVAq07x20xvEncxIr21l5I8CrVACY4xI 64kE6c02F40Ex7xfMcIj6xIIjxv20xvE14v26r1Y6r17McIj6I8E87Iv67AKxVWUJVW8Jw Am72CE4IkC6x0Yz7v_Jr0_Gr1lF7xvr2IYc2Ij64vIr41lF7I21c0EjII2zVCS5cI20VAG YxC7M4IIrI8v6xkF7I0E8cxan2IY04v7MxkIecxEwVAFwVW5JwCF04k20xvY0x0EwIxGrw CFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F40E14v26r1j6r18MI8I3I0E7480Y4vE 14v26r106r1rMI8E67AF67kF1VAFwI0_Jw0_GFylIxkGc2Ij64vIr41lIxAIcVC0I7IYx2 IY67AKxVWUJVWUCwCI42IY6xIIjxv20xvEc7CjxVAFwI0_Gr0_Cr1lIxAIcVCF04k26cxK x2IYs7xG6rWUJVWrZr1UMIIF0xvEx4A2jsIE14v26r1j6r4UMIIF0xvEx4A2jsIEc7CjxV AFwI0_Gr0_Gr1UYxBIdaVFxhVjvjDU0xZFpf9x0JUqXdUUUUUU= X-CM-SenderInfo: irzsiiysuqikmy6i3vldqovvfxof0/ Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org In sctp_skb_recv_datagram(), the function fetch a sk_buff object from the receiving queue to "skb" by calling skb_peek() or __skb_dequeue() and return its reference to the caller. However, when calling __skb_dequeue() successfully, the function forgets to hold a reference count of the "skb" object and directly return it, causing a potential memory leak in the caller function. Fix this issue by calling refcount_inc after __skb_dequeue() successfully executed. Signed-off-by: Xiyu Yang Signed-off-by: Xin Tan Reported-by: kernel test robot Reported-by: kernel test robot --- net/sctp/socket.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/net/sctp/socket.c b/net/sctp/socket.c index d57e1a002ffc..4c8f0b83efd0 100644 --- a/net/sctp/socket.c +++ b/net/sctp/socket.c @@ -8990,6 +8990,8 @@ struct sk_buff *sctp_skb_recv_datagram(struct sock *sk, int flags, refcount_inc(&skb->users); } else { skb = __skb_dequeue(&sk->sk_receive_queue); + if (skb) + refcount_inc(&skb->users); } if (skb)