From patchwork Sun Mar 7 04:25:02 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Marek_Beh=C3=BAn?= X-Patchwork-Id: 1448573 X-Patchwork-Delegate: trini@ti.com Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=lists.denx.de (client-ip=85.214.62.61; helo=phobos.denx.de; envelope-from=u-boot-bounces@lists.denx.de; receiver=) Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; secure) header.d=nic.cz header.i=@nic.cz header.a=rsa-sha256 header.s=default header.b=bgjfotHB; dkim-atps=neutral Received: from phobos.denx.de (phobos.denx.de [85.214.62.61]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 4DtT2k6VhJz9sW8 for ; Sun, 7 Mar 2021 15:27:10 +1100 (AEDT) Received: from h2850616.stratoserver.net (localhost [IPv6:::1]) by phobos.denx.de (Postfix) with ESMTP id 54B20827BC; Sun, 7 Mar 2021 05:26:23 +0100 (CET) Authentication-Results: phobos.denx.de; dmarc=pass (p=none dis=none) header.from=nic.cz Authentication-Results: phobos.denx.de; spf=pass smtp.mailfrom=u-boot-bounces@lists.denx.de Authentication-Results: phobos.denx.de; dkim=pass (1024-bit key; secure) header.d=nic.cz header.i=@nic.cz header.b="bgjfotHB"; dkim-atps=neutral Received: by phobos.denx.de (Postfix, from userid 109) id 7AF7C8276B; Sun, 7 Mar 2021 05:26:13 +0100 (CET) X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on phobos.denx.de X-Spam-Level: X-Spam-Status: No, score=-2.0 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,RCVD_IN_MSPIKE_H3,RCVD_IN_MSPIKE_WL, SPF_HELO_NONE autolearn=ham autolearn_force=no version=3.4.2 Received: from mail.nic.cz (lists.nic.cz [217.31.204.67]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by phobos.denx.de (Postfix) with ESMTPS id 3932E82652 for ; Sun, 7 Mar 2021 05:26:06 +0100 (CET) Authentication-Results: phobos.denx.de; dmarc=pass (p=none dis=none) header.from=nic.cz Authentication-Results: phobos.denx.de; spf=pass smtp.mailfrom=marek.behun@nic.cz Received: from dellmb.labs.office.nic.cz (unknown [IPv6:2001:1488:fffe:6:cac7:3539:7f1f:463]) by mail.nic.cz (Postfix) with ESMTPSA id BB2BB140A37; Sun, 7 Mar 2021 05:26:05 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=nic.cz; s=default; t=1615091165; bh=oZccO93XVOiRg7xkrXIkWBuMLMG7buafczSM3l9DnlA=; h=From:To:Date; b=bgjfotHBlhOqHjjN57Z0II4pu1/sbE4+OSskOsQXXYtoAu9lUiqswgC1gMNARSG5V OXbqcvYwEUbocSurmJN5r+lQ7+awI50ivcZdSFMkkb0UXG4j63L+F8zr2LJNuHSkpc GyAmSiUwrBzBzGS4qO7c9cRo+h2tr+tFZgFiXAFw= From: =?utf-8?q?Marek_Beh=C3=BAn?= To: u-boot@lists.denx.de, Simon Glass , Heiko Schocher , Patrick Delaunay , Patrice CHOTARD , Miquel Raynal , Tom Rini , =?utf-8?q?Pali_Roh=C3=A1r?= , Stefan Roese , Heinrich Schuchardt , Alexander Graf , Marek Vasut , Neil Armstrong , Ryder Lee , Adam Ford , Bin Meng Cc: =?utf-8?q?Marek_Beh=C3=BAn?= Subject: [PATCH u-boot-dm 03/39] regmap: fix a serious pointer casting bug Date: Sun, 7 Mar 2021 05:25:02 +0100 Message-Id: <20210307042538.21229-4-marek.behun@nic.cz> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20210307042538.21229-1-marek.behun@nic.cz> References: <20210307042538.21229-1-marek.behun@nic.cz> MIME-Version: 1.0 X-BeenThere: u-boot@lists.denx.de X-Mailman-Version: 2.1.34 Precedence: list List-Id: U-Boot discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: u-boot-bounces@lists.denx.de Sender: "U-Boot" X-Virus-Scanned: clamav-milter 0.102.4 at phobos.denx.de X-Virus-Status: Clean There is a serious bug in regmap_read() and regmap_write() functions where an uint pointer is cast to (void *) which is then cast to (u8 *), (u16 *), (u32 *) or (u64 *), depending on register width of the map. For example given a regmap with 16-bit register width the code int val = 0x12340000; regmap_read(map, 0, &val); only changes the lower 16 bits of val on little-endian machines. The upper 16 bits will remain 0x1234. Nobody noticed this probably because this bug can be triggered with regmap_write() only on big-endian architectures (which are not used by many people anymore), and on little endian this bug has consequences only if register width is 8 or 16 bits and also the memory place to which regmap_read() should store it's result has non-zero upper bits, which it seems doesn't happen anywhere in U-Boot normally. CI managed to trigger this bug in unit test of dm_test_devm_regmap_field when compiled for sandbox_defconfig using LTO. Fix this simply by taking into account that regmap_raw_read() and regmap_raw_write() behave as if the data given to these functions were in little-endian format, i.e. use cpu_to_le32() / le32_to_cpu(). In regmap_read() also zero out the space so that we don't get invalid result if regmap_raw_read() does not fill the whole object. Signed-off-by: Marek Behún Reviewed-by: Simon Glass Reviewed-by: Heiko Schocher Reviewed-by: Bin Meng --- drivers/core/regmap.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) diff --git a/drivers/core/regmap.c b/drivers/core/regmap.c index b51ce108c1..5d37006fff 100644 --- a/drivers/core/regmap.c +++ b/drivers/core/regmap.c @@ -435,7 +435,16 @@ int regmap_raw_read(struct regmap *map, uint offset, void *valp, size_t val_len) int regmap_read(struct regmap *map, uint offset, uint *valp) { - return regmap_raw_read(map, offset, valp, map->width); + int res; + + *valp = 0; + res = regmap_raw_read(map, offset, valp, map->width); + if (res) + return res; + + *valp = le32_to_cpu(*valp); + + return 0; } static inline void __write_8(u8 *addr, const u8 *val, @@ -546,6 +555,8 @@ int regmap_raw_write(struct regmap *map, uint offset, const void *val, int regmap_write(struct regmap *map, uint offset, uint val) { + val = cpu_to_le32(val); + return regmap_raw_write(map, offset, &val, map->width); }