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 D3BC3C43217 for ; Tue, 18 Jan 2022 03:04:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1353743AbiARDEa (ORCPT ); Mon, 17 Jan 2022 22:04:30 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37240 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1353637AbiARDCQ (ORCPT ); Mon, 17 Jan 2022 22:02:16 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C40E9C08EBAF; Mon, 17 Jan 2022 18:47:42 -0800 (PST) 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 49FB6612D1; Tue, 18 Jan 2022 02:47:42 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id E3055C36AEB; Tue, 18 Jan 2022 02:47:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1642474061; bh=NZ86/jhMQ53LYMnML1i/s5E3FRSxzSncXmKzzl4r9Tk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=WRgmYrPRpKL5Y/1g3i9QzOwW8BXSokcBol5ywDdQr1x/r/Us1ZgaHREKseabCNlWr xsBDMVtOu69Fi1zKur7YOa5wbpu4aFKWYdxUBYaeHAIjkFRj3kZzPtJeLIifC5IaMt nQyrBq99se8JyaLetW45ilItTQ7on7C+Mo+CYXB7rsV2PU+LmSEsOkAyTLGwW6XPBy WipHCrHL/ctzkG8vVCU89LnbbSVUtCoNJiBvJnzsXN2XwotxW3Isg+KXL5727Q0oSf phJjt8lOb0txDqHtXBQJHnZurR8ZfRSyIf4vaYDUONvftv9u8W5tliCwAnqmhWH+za EyHZ2h2a9UYpg== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Mauro Carvalho Chehab , rkardell@mida.se, Sasha Levin , mchehab@kernel.org, linux-media@vger.kernel.org Subject: [PATCH AUTOSEL 4.19 19/59] media: m920x: don't use stack on USB reads Date: Mon, 17 Jan 2022 21:46:20 -0500 Message-Id: <20220118024701.1952911-19-sashal@kernel.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220118024701.1952911-1-sashal@kernel.org> References: <20220118024701.1952911-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Mauro Carvalho Chehab [ Upstream commit a2ab06d7c4d6bfd0b545a768247a70463e977e27 ] Using stack-allocated pointers for USB message data don't work. This driver is almost OK with that, except for the I2C read logic. Fix it by using a temporary read buffer, just like on all other calls to m920x_read(). Link: https://lore.kernel.org/all/ccc99e48-de4f-045e-0fe4-61e3118e3f74@mida.se/ Reported-by: rkardell@mida.se Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Sasha Levin --- drivers/media/usb/dvb-usb/m920x.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/drivers/media/usb/dvb-usb/m920x.c b/drivers/media/usb/dvb-usb/m920x.c index 22554d9abd432..3b2a0f36fc38e 100644 --- a/drivers/media/usb/dvb-usb/m920x.c +++ b/drivers/media/usb/dvb-usb/m920x.c @@ -277,6 +277,13 @@ static int m920x_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msg[], int nu /* Should check for ack here, if we knew how. */ } if (msg[i].flags & I2C_M_RD) { + char *read = kmalloc(1, GFP_KERNEL); + if (!read) { + ret = -ENOMEM; + kfree(read); + goto unlock; + } + for (j = 0; j < msg[i].len; j++) { /* Last byte of transaction? * Send STOP, otherwise send ACK. */ @@ -284,9 +291,12 @@ static int m920x_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msg[], int nu if ((ret = m920x_read(d->udev, M9206_I2C, 0x0, 0x20 | stop, - &msg[i].buf[j], 1)) != 0) + read, 1)) != 0) goto unlock; + msg[i].buf[j] = read[0]; } + + kfree(read); } else { for (j = 0; j < msg[i].len; j++) { /* Last byte of transaction? Then send STOP. */ -- 2.34.1