From patchwork Mon Apr 24 18:33:48 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Fedor Pchelkin X-Patchwork-Id: 678004 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 1D1F5C77B61 for ; Mon, 24 Apr 2023 18:34:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232341AbjDXSek (ORCPT ); Mon, 24 Apr 2023 14:34:40 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37334 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230525AbjDXSeh (ORCPT ); Mon, 24 Apr 2023 14:34:37 -0400 Received: from mail.ispras.ru (mail.ispras.ru [83.149.199.84]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C8A84FA; Mon, 24 Apr 2023 11:34:35 -0700 (PDT) Received: from fpc.. (unknown [46.242.14.200]) by mail.ispras.ru (Postfix) with ESMTPSA id E9104407626E; Mon, 24 Apr 2023 18:34:33 +0000 (UTC) DKIM-Filter: OpenDKIM Filter v2.11.0 mail.ispras.ru E9104407626E DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ispras.ru; s=default; t=1682361274; bh=PRIdr5ITnjkysoIatNA0p/ZUHeBN+gItyLquEJcHG7M=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=arVHo42+Ms6WNHPJyjNBUnplzA0d9vVLl2ngnRfDxQfxKyEhT8O+CQ4Xcg4WqSC5t B/0auEjXE9IJtc7O+G6E9hGnvM/WO2hxv5WJct1uGgLGzaNqga2ju7YEVOMWzM15zI cDJQqWtZFJZ76UqDBc9ooPjDwclyUJ5zctUpgbq4= From: Fedor Pchelkin To: =?utf-8?q?Toke_H=C3=B8iland-J=C3=B8rgensen?= , Kalle Vallo Cc: Fedor Pchelkin , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Senthil Balasubramanian , "John W. Linville" , Vasanthakumar Thiagarajan , Sujith , linux-wireless@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Alexey Khoroshilov , lvc-project@linuxtesting.org, syzbot+f2cb6e0ffdb961921e4d@syzkaller.appspotmail.com Subject: [PATCH v2] wifi: ath9k: avoid referencing uninit memory in ath9k_wmi_ctrl_rx Date: Mon, 24 Apr 2023 21:33:48 +0300 Message-Id: <20230424183348.111355-1-pchelkin@ispras.ru> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230424182300.sw5ogmcst5suf2ab@fpc> References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org For the reasons also described in commit b383e8abed41 ("wifi: ath9k: avoid uninit memory read in ath9k_htc_rx_msg()"), ath9k_htc_rx_msg() should validate pkt_len before accessing the SKB. For example, the obtained SKB may have been badly constructed with pkt_len = 8. In this case, the SKB can only contain a valid htc_frame_hdr but after being processed in ath9k_htc_rx_msg() and passed to ath9k_wmi_ctrl_rx() endpoint RX handler, it is expected to have a WMI command header which should be located inside its data payload. Implement sanity checking inside ath9k_wmi_ctrl_rx(). Otherwise, uninit memory can be referenced. Tested on Qualcomm Atheros Communications AR9271 802.11n . Found by Linux Verification Center (linuxtesting.org) with Syzkaller. Fixes: fb9987d0f748 ("ath9k_htc: Support for AR9271 chipset.") Reported-and-tested-by: syzbot+f2cb6e0ffdb961921e4d@syzkaller.appspotmail.com Signed-off-by: Fedor Pchelkin --- v2: remove incorrect checks and rephrase commit info drivers/net/wireless/ath/ath9k/wmi.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/net/wireless/ath/ath9k/wmi.c b/drivers/net/wireless/ath/ath9k/wmi.c index 19345b8f7bfd..d652c647d56b 100644 --- a/drivers/net/wireless/ath/ath9k/wmi.c +++ b/drivers/net/wireless/ath/ath9k/wmi.c @@ -221,6 +221,10 @@ static void ath9k_wmi_ctrl_rx(void *priv, struct sk_buff *skb, if (unlikely(wmi->stopped)) goto free_skb; + /* Validate the obtained SKB. */ + if (unlikely(skb->len < sizeof(struct wmi_cmd_hdr))) + goto free_skb; + hdr = (struct wmi_cmd_hdr *) skb->data; cmd_id = be16_to_cpu(hdr->command_id);