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 X-Spam-Level: X-Spam-Status: No, score=-8.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E8AB2C43613 for ; Thu, 20 Jun 2019 18:32:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BAF5A20665 for ; Thu, 20 Jun 2019 18:32:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1561055573; bh=x2Cwme/mAmbXafu9IFLqh+c2ruPE+Y+FSlL6DQk24qE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=EfWsN+QRhBL3WD2l89zMN987OrAioBjVnKYbBd9Cco7ZR213ZT1/SVtCn8ZsmIKEb UzJAnDo/Oqzyz7v1qVsD1cKXtSolAupTUlipNs7RfhTtF53g7X0Vwpd2P9uMDQ05C3 AdmhLlYmfuHColYbJM0y5WaFRkMD1kZ3Qy36hVR0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726180AbfFTR6k (ORCPT ); Thu, 20 Jun 2019 13:58:40 -0400 Received: from mail.kernel.org ([198.145.29.99]:45432 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726127AbfFTR6j (ORCPT ); Thu, 20 Jun 2019 13:58:39 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id F030F215EA; Thu, 20 Jun 2019 17:58:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1561053519; bh=x2Cwme/mAmbXafu9IFLqh+c2ruPE+Y+FSlL6DQk24qE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=mtQyqskhVkoiIadmINN8Nmv5WrLdwPRaatMo1N6ZEJ1in5LZEXXKBIZS11QKeBF7c /dY8cxmOekVyJs02pcGLwWxi3GWKQ5FhTAYtFJ9sfViOdl5y8RFkzertA3Wz9MM6Pz 1zrVJiDIXUdxBuFoK5KhfvafvXB5rQMW38Zs4588= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jorge Ramirez-Ortiz , Srinivas Kandagatla , Sasha Levin Subject: [PATCH 4.4 17/84] nvmem: core: fix read buffer in place Date: Thu, 20 Jun 2019 19:56:14 +0200 Message-Id: <20190620174340.085178846@linuxfoundation.org> X-Mailer: git-send-email 2.22.0 In-Reply-To: <20190620174337.538228162@linuxfoundation.org> References: <20190620174337.538228162@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org [ Upstream commit 2fe518fecb3a4727393be286db9804cd82ee2d91 ] When the bit_offset in the cell is zero, the pointer to the msb will not be properly initialized (ie, will still be pointing to the first byte in the buffer). This being the case, if there are bits to clear in the msb, those will be left untouched while the mask will incorrectly clear bit positions on the first byte. This commit also makes sure that any byte unused in the cell is cleared. Signed-off-by: Jorge Ramirez-Ortiz Signed-off-by: Srinivas Kandagatla Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- drivers/nvmem/core.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) diff --git a/drivers/nvmem/core.c b/drivers/nvmem/core.c index 6fd4e5a5ef4a..931cc33e46f0 100644 --- a/drivers/nvmem/core.c +++ b/drivers/nvmem/core.c @@ -789,7 +789,7 @@ static inline void nvmem_shift_read_buffer_in_place(struct nvmem_cell *cell, void *buf) { u8 *p, *b; - int i, bit_offset = cell->bit_offset; + int i, extra, bit_offset = cell->bit_offset; p = b = buf; if (bit_offset) { @@ -804,11 +804,16 @@ static inline void nvmem_shift_read_buffer_in_place(struct nvmem_cell *cell, p = b; *b++ >>= bit_offset; } - - /* result fits in less bytes */ - if (cell->bytes != DIV_ROUND_UP(cell->nbits, BITS_PER_BYTE)) - *p-- = 0; + } else { + /* point to the msb */ + p += cell->bytes - 1; } + + /* result fits in less bytes */ + extra = cell->bytes - DIV_ROUND_UP(cell->nbits, BITS_PER_BYTE); + while (--extra >= 0) + *p-- = 0; + /* clear msb bits if any leftover in the last byte */ *p &= GENMASK((cell->nbits%BITS_PER_BYTE) - 1, 0); } -- 2.20.1