From nobody Wed Dec 17 09:14:22 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 AE036C49EC5 for ; Tue, 23 Aug 2022 10:42:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1356209AbiHWKll (ORCPT ); Tue, 23 Aug 2022 06:41:41 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52626 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1354273AbiHWK1c (ORCPT ); Tue, 23 Aug 2022 06:27:32 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 66A7B84ED3; Tue, 23 Aug 2022 02:06:00 -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 ams.source.kernel.org (Postfix) with ESMTPS id 1C6DFB81C86; Tue, 23 Aug 2022 09:05:59 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7673BC43148; Tue, 23 Aug 2022 09:05:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1661245557; bh=ZWz5xNRGqs4DFUsiTNXMxvF7ZS3YmBi3o4+3EdUiwWc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=R/GaJmr3oa9em2R1XO6AiqjF/nnjPK+u/yoTLODznWYpVkq/gM273BnB9Jz9zmwKi JiMWxqtK1XtBSUBN+PPWfAOCoUvK9p5PcPiCttKodudtN675uvpp3UVZNH6IErXMiD GBFJIMbk3l3pR95Ct4jBrovpSfPhFFpeZMscC+jk= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Harshit Mogalapalli , Jiri Kosina , Sasha Levin Subject: [PATCH 4.19 116/287] HID: cp2112: prevent a buffer overflow in cp2112_xfer() Date: Tue, 23 Aug 2022 10:24:45 +0200 Message-Id: <20220823080104.297228396@linuxfoundation.org> X-Mailer: git-send-email 2.37.2 In-Reply-To: <20220823080100.268827165@linuxfoundation.org> References: <20220823080100.268827165@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Harshit Mogalapalli [ Upstream commit 381583845d19cb4bd21c8193449385f3fefa9caf ] Smatch warnings: drivers/hid/hid-cp2112.c:793 cp2112_xfer() error: __memcpy() 'data->block[1]' too small (33 vs 255) drivers/hid/hid-cp2112.c:793 cp2112_xfer() error: __memcpy() 'buf' too small (64 vs 255) The 'read_length' variable is provided by 'data->block[0]' which comes from user and it(read_length) can take a value between 0-255. Add an upper bound to 'read_length' variable to prevent a buffer overflow in memcpy(). Fixes: 542134c0375b ("HID: cp2112: Fix I2C_BLOCK_DATA transactions") Signed-off-by: Harshit Mogalapalli Signed-off-by: Jiri Kosina Signed-off-by: Sasha Levin --- drivers/hid/hid-cp2112.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/hid/hid-cp2112.c b/drivers/hid/hid-cp2112.c index 6f65f5257236..637a7ce281c6 100644 --- a/drivers/hid/hid-cp2112.c +++ b/drivers/hid/hid-cp2112.c @@ -794,6 +794,11 @@ static int cp2112_xfer(struct i2c_adapter *adap, u16 a= ddr, data->word =3D le16_to_cpup((__le16 *)buf); break; case I2C_SMBUS_I2C_BLOCK_DATA: + if (read_length > I2C_SMBUS_BLOCK_MAX) { + ret =3D -EINVAL; + goto power_normal; + } + memcpy(data->block + 1, buf, read_length); break; case I2C_SMBUS_BLOCK_DATA: --=20 2.35.1