From nobody Wed Sep 3 06:24:53 2025 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 E0FAEECAAA1 for ; Mon, 24 Oct 2022 12:32:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231358AbiJXMcX (ORCPT ); Mon, 24 Oct 2022 08:32:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47702 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233954AbiJXM3F (ORCPT ); Mon, 24 Oct 2022 08:29:05 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 529F45591; Mon, 24 Oct 2022 05:02:53 -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 C8637612E3; Mon, 24 Oct 2022 12:02:31 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D24C7C433C1; Mon, 24 Oct 2022 12:02:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1666612951; bh=m/QdiEsyaqsXyeYZVuoxXTWReCx/204ZsauJ1OlEs0U=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=edw7Nym8mBVrLAJwlpVZG/MpX7AZRYNKPYs03A+BoxBW0awT2wsAHDCrp1cS8OCon 7IXBBt5xoopfHTZdD3FdxSttQpEIm2czBCNDifHnedzIIa2gVwz0h20He+4QqmJ/h+ B+xQ+g9BclVFPMxT+HM4fcef4LChXruVKKR1+x78= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, syzbot , Tetsuo Handa , =?UTF-8?q?Toke=20H=C3=B8iland-J=C3=B8rgensen?= , Kalle Valo , Sasha Levin Subject: [PATCH 4.19 180/229] wifi: ath9k: avoid uninit memory read in ath9k_htc_rx_msg() Date: Mon, 24 Oct 2022 13:31:39 +0200 Message-Id: <20221024113004.915215859@linuxfoundation.org> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221024112959.085534368@linuxfoundation.org> References: <20221024112959.085534368@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Tetsuo Handa [ Upstream commit b383e8abed41cc6ff1a3b34de75df9397fa4878c ] syzbot is reporting uninit value at ath9k_htc_rx_msg() [1], for ioctl(USB_RAW_IOCTL_EP_WRITE) can call ath9k_hif_usb_rx_stream() with pkt_len =3D 0 but ath9k_hif_usb_rx_stream() uses __dev_alloc_skb(pkt_len + 32, GFP_ATOMIC) based on an assumption that pkt_len is valid. As a result, ath9k_hif_usb_rx_stream() allocates skb with uninitialized memory and ath9k_htc_rx_msg() is reading from uninitialized memory. Since bytes accessed by ath9k_htc_rx_msg() is not known until ath9k_htc_rx_msg() is called, it would be difficult to check minimal valid pkt_len at "if (pkt_len > 2 * MAX_RX_BUF_SIZE) {" line in ath9k_hif_usb_rx_stream(). We have two choices. One is to workaround by adding __GFP_ZERO so that ath9k_htc_rx_msg() sees 0 if pkt_len is invalid. The other is to let ath9k_htc_rx_msg() validate pkt_len before accessing. This patch chose the latter. Note that I'm not sure threshold condition is correct, for I can't find details on possible packet length used by this protocol. Link: https://syzkaller.appspot.com/bug?extid=3D2ca247c2d60c7023de7f [1] Reported-by: syzbot Signed-off-by: Tetsuo Handa Acked-by: Toke H=C3=B8iland-J=C3=B8rgensen Signed-off-by: Kalle Valo Link: https://lore.kernel.org/r/7acfa1be-4b5c-b2ce-de43-95b0593fb3e5@I-love= .SAKURA.ne.jp Signed-off-by: Sasha Levin --- drivers/net/wireless/ath/ath9k/htc_hst.c | 43 +++++++++++++++--------- 1 file changed, 28 insertions(+), 15 deletions(-) diff --git a/drivers/net/wireless/ath/ath9k/htc_hst.c b/drivers/net/wireles= s/ath/ath9k/htc_hst.c index e37de14bc502..6d69cf69fd86 100644 --- a/drivers/net/wireless/ath/ath9k/htc_hst.c +++ b/drivers/net/wireless/ath/ath9k/htc_hst.c @@ -367,33 +367,27 @@ void ath9k_htc_txcompletion_cb(struct htc_target *htc= _handle, } =20 static void ath9k_htc_fw_panic_report(struct htc_target *htc_handle, - struct sk_buff *skb) + struct sk_buff *skb, u32 len) { uint32_t *pattern =3D (uint32_t *)skb->data; =20 - switch (*pattern) { - case 0x33221199: - { + if (*pattern =3D=3D 0x33221199 && len >=3D sizeof(struct htc_panic_bad_va= ddr)) { struct htc_panic_bad_vaddr *htc_panic; htc_panic =3D (struct htc_panic_bad_vaddr *) skb->data; dev_err(htc_handle->dev, "ath: firmware panic! " "exccause: 0x%08x; pc: 0x%08x; badvaddr: 0x%08x.\n", htc_panic->exccause, htc_panic->pc, htc_panic->badvaddr); - break; - } - case 0x33221299: - { + return; + } + if (*pattern =3D=3D 0x33221299) { struct htc_panic_bad_epid *htc_panic; htc_panic =3D (struct htc_panic_bad_epid *) skb->data; dev_err(htc_handle->dev, "ath: firmware panic! " "bad epid: 0x%08x\n", htc_panic->epid); - break; - } - default: - dev_err(htc_handle->dev, "ath: unknown panic pattern!\n"); - break; + return; } + dev_err(htc_handle->dev, "ath: unknown panic pattern!\n"); } =20 /* @@ -414,16 +408,26 @@ void ath9k_htc_rx_msg(struct htc_target *htc_handle, if (!htc_handle || !skb) return; =20 + /* A valid message requires len >=3D 8. + * + * sizeof(struct htc_frame_hdr) =3D=3D 8 + * sizeof(struct htc_ready_msg) =3D=3D 8 + * sizeof(struct htc_panic_bad_vaddr) =3D=3D 16 + * sizeof(struct htc_panic_bad_epid) =3D=3D 8 + */ + if (unlikely(len < sizeof(struct htc_frame_hdr))) + goto invalid; htc_hdr =3D (struct htc_frame_hdr *) skb->data; epid =3D htc_hdr->endpoint_id; =20 if (epid =3D=3D 0x99) { - ath9k_htc_fw_panic_report(htc_handle, skb); + ath9k_htc_fw_panic_report(htc_handle, skb, len); kfree_skb(skb); return; } =20 if (epid < 0 || epid >=3D ENDPOINT_MAX) { +invalid: if (pipe_id !=3D USB_REG_IN_PIPE) dev_kfree_skb_any(skb); else @@ -435,21 +439,30 @@ void ath9k_htc_rx_msg(struct htc_target *htc_handle, =20 /* Handle trailer */ if (htc_hdr->flags & HTC_FLAGS_RECV_TRAILER) { - if (be32_to_cpu(*(__be32 *) skb->data) =3D=3D 0x00C60000) + if (be32_to_cpu(*(__be32 *) skb->data) =3D=3D 0x00C60000) { /* Move past the Watchdog pattern */ htc_hdr =3D (struct htc_frame_hdr *)(skb->data + 4); + len -=3D 4; + } } =20 /* Get the message ID */ + if (unlikely(len < sizeof(struct htc_frame_hdr) + sizeof(__be16))) + goto invalid; msg_id =3D (__be16 *) ((void *) htc_hdr + sizeof(struct htc_frame_hdr)); =20 /* Now process HTC messages */ switch (be16_to_cpu(*msg_id)) { case HTC_MSG_READY_ID: + if (unlikely(len < sizeof(struct htc_ready_msg))) + goto invalid; htc_process_target_rdy(htc_handle, htc_hdr); break; case HTC_MSG_CONNECT_SERVICE_RESPONSE_ID: + if (unlikely(len < sizeof(struct htc_frame_hdr) + + sizeof(struct htc_conn_svc_rspmsg))) + goto invalid; htc_process_conn_rsp(htc_handle, htc_hdr); break; default: --=20 2.35.1