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 EFFFDC433FE for ; Tue, 18 Jan 2022 03:16:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1350298AbiARDOl (ORCPT ); Mon, 17 Jan 2022 22:14:41 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38948 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1348467AbiARDIc (ORCPT ); Mon, 17 Jan 2022 22:08:32 -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 48EF5C0619C0; Mon, 17 Jan 2022 18:50:15 -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 DA0BF612E8; Tue, 18 Jan 2022 02:50:14 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 83953C36AE3; Tue, 18 Jan 2022 02:50:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1642474214; bh=0ierq2hC0x5LeWSevBtfA0k91FVROzcHK/4VaadK2lE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ARqb/+vP81pfHwBybMNLsaNrXFBq3LugCNHhB2nvt7Pv57Rgxu2pZvqg3SjpGuSFe NglyFQaoq3U8c5XNjd+bs/zRjHNp30NccpG8sYE851rFmHnhW/MFpXPQ7f+Qs0dAGx eJ9NnAPyfB1yUxC8jPN1fGVrWyVVsvOTnxMcY6pgkgZcW9ztoVOGAs5W8LgstA4ynk gSke9ylrVVCwS9b8Q39fZWqZKZlbrvSWfDevBoYKoGMkzIlpFsUcXMKt39l/tsZzQX 5TOmdxw0EBSmwZnL9nwQm8J1B3qQlRt6GmwV4SVr6pRfsm3fwlJqxdX58EjOc01WeF Qw1ok9nE2JpWw== 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 4.14 26/56] media: m920x: don't use stack on USB reads Date: Mon, 17 Jan 2022 21:48:38 -0500 Message-Id: <20220118024908.1953673-26-sashal@kernel.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220118024908.1953673-1-sashal@kernel.org> References: <20220118024908.1953673-1-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 32081c2ce0da8..8a43e2415686a 100644 --- a/drivers/media/usb/dvb-usb/m920x.c +++ b/drivers/media/usb/dvb-usb/m920x.c @@ -280,6 +280,13 @@ 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. */ @@ -287,9 +294,12 @@ 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