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=-9.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,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 60C36C33CA9 for ; Mon, 13 Jan 2020 18:21:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2A2C0207E0 for ; Mon, 13 Jan 2020 18:21:11 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=nbd.name header.i=@nbd.name header.b="tDNHg+NK" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728665AbgAMSVK (ORCPT ); Mon, 13 Jan 2020 13:21:10 -0500 Received: from nbd.name ([46.4.11.11]:38002 "EHLO nbd.name" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728633AbgAMSVK (ORCPT ); Mon, 13 Jan 2020 13:21:10 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=nbd.name; s=20160729; h=Content-Transfer-Encoding:MIME-Version:Message-Id:Date:Subject :Cc:To:From:Sender:Reply-To:Content-Type:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: In-Reply-To:References:List-Id:List-Help:List-Unsubscribe:List-Subscribe: List-Post:List-Owner:List-Archive; bh=jfg1CH/BWu8y14E87TMalUIfmXnxxWjXnaCMLIpLMCA=; b=tDNHg+NKl0rDlws2ygYpd0woxj 6Mn2WR2FddwrqoSFd5f5s2YQsRrVT/RrFtXpWCBSZ6pCi08n/VmEYwE6CQIw1vnlfuGKo+0igiUUu U2DKmEAOzdUv1Tggk/jsRh8C+hLC50SBylE94bz9VbK71hHR5TyDE5p4pjc3NWwIguoo=; Received: from [80.255.7.117] (helo=maeck.local) by ds12 with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1ir4Kq-0005oU-PE; Mon, 13 Jan 2020 19:21:08 +0100 Received: by maeck.local (Postfix, from userid 501) id D159777EB435; Mon, 13 Jan 2020 19:21:07 +0100 (CET) From: Felix Fietkau To: linux-wireless@vger.kernel.org Cc: johannes@sipsolutions.net Subject: [PATCH 5.5] cfg80211: fix page refcount issue in A-MSDU decap Date: Mon, 13 Jan 2020 19:21:07 +0100 Message-Id: <20200113182107.20461-1-nbd@nbd.name> X-Mailer: git-send-email 2.24.0 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-wireless-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org The fragments attached to a skb can be part of a compound page. In that case, page_ref_inc will increment the refcount for the wrong page. Fix this by using get_page instead, which calls page_ref_inc on the compound head and also checks for overflow. Fixes: 2b67f944f88c ("cfg80211: reuse existing page fragments in A-MSDU rx") Cc: stable@vger.kernel.org Signed-off-by: Felix Fietkau --- net/wireless/util.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/wireless/util.c b/net/wireless/util.c index 5b4ed5bbc542..8481e9ac33da 100644 --- a/net/wireless/util.c +++ b/net/wireless/util.c @@ -564,7 +564,7 @@ __frame_add_frag(struct sk_buff *skb, struct page *page, struct skb_shared_info *sh = skb_shinfo(skb); int page_offset; - page_ref_inc(page); + get_page(page); page_offset = ptr - page_address(page); skb_add_rx_frag(skb, sh->nr_frags, page, page_offset, len, size); } -- 2.24.0