From patchwork Thu Oct 27 03:32:09 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: ChiYuan Huang X-Patchwork-Id: 13021552 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 3507BC38A2D for ; Thu, 27 Oct 2022 03:33:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Message-Id:Date:Subject:Cc: To:From:Reply-To:MIME-Version:Content-Type:Content-Transfer-Encoding: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References:List-Owner; bh=h7yF1dXBnJEVhGGTIzHbHbpBrHmE7RRuUtKfNdRHcto=; b=QUREOPLojXHQu4rsbkYgUAlnIF LOC8IhKqUmzY1qZDQDX6ROm7aEEq02WmOX6pkhk0WT68D2Vib3seCiN2V5nFsoHJlElS9eP8V0+iN mjfqK7vctIjwWuAHASpOX+i+KF6aGTZZCWe+b2/gYvMlJ9JWO8G5srJqmtw1FxvoSADEvUBmThPAi eK9BYKPM9hLMcEXc+r/7GQJXNB44q/RApe9Kl92M63LEgaVN0ZYYvTBgkjtN9ZbsOLzuXDNVz2WeL qsN6jIZ6H7jYB7yyqfAoDdB4m0MR0axRNpeWxWmn/nsF/36rb5SdvbLMlX+jkTt7pW3XdB2GE652Q cFYb1KjQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1ontdX-00BiKX-N5; Thu, 27 Oct 2022 03:32:55 +0000 Received: from mail-pj1-x102b.google.com ([2607:f8b0:4864:20::102b]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1ontd6-00BiI1-Ro; Thu, 27 Oct 2022 03:32:32 +0000 Received: by mail-pj1-x102b.google.com with SMTP id m14-20020a17090a3f8e00b00212dab39bcdso5059202pjc.0; Wed, 26 Oct 2022 20:32:23 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=h7yF1dXBnJEVhGGTIzHbHbpBrHmE7RRuUtKfNdRHcto=; b=gu6eTOkZtN4JP0DfX2VwONvMw+YB9vTjBp2U/9eEjpWrIdTvvb/NT8IBB/HSfr77T/ KVU109xPoqhChnO4jEJJeNoR4PxuEiH/nAXSGrDwiBwAXDYj5CYtkIuQ1KlG5Q4jPy2a /mw69vD27HVRoam4QlHY4I8x6oJdbrxeOUjLEnJsyCgctGEqkezSz0C/2pICsRoGWGW1 KKDcghoA6uiFfa96jQd/mQ8IQ/ySUBgXYphkyeiQYOdMfa2rNBeOauCMLxN1f6kzy/FU OPiSipbCxduZWTiG2SbeVpLYiA2gE90MJeOgKT9NtDNr4li1Lki+e+3JtuJxOzvZha/K eiHw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=h7yF1dXBnJEVhGGTIzHbHbpBrHmE7RRuUtKfNdRHcto=; b=BshEQJBVZ5Rq8zkvh+aJ8+MvUOngcyHvtqI0pt0aTAdupM1pVZgiwACDbHXVjL1v0Y Slx4w9AXL8F7QdMQ3RhHoERBl7NXIiTcSFjHGJK4uUx1f1EnKmRvDvKfHLp73guCNoDR Mx62jPWvX9ht8MuZJO9UUHSvNl4BQg4mG7GHFpStzDX9oLFBJaQqB/An0qtpHxHec4UR ITpF4D+R1l/P/ddXaerFZ3nbGMcpQR7lhaNcFEUth1XNQxiqMFD70rLerdyA19gvhgDe iPsQfn0mhvHfCossZOsMlsbUNe6rE6UTVmefZQLFUYUtvyHW4/d4qY2TbRbWQ7XRsb9b oiVQ== X-Gm-Message-State: ACrzQf2ISYLIizJBAU1EMXoshlNCe3s2/rDsQxxfzCjd3R7a4zdNfaU7 XdGxFr3J+UlORql2XG3C7f2isvJ5/O4= X-Google-Smtp-Source: AMsMyM6oUvd42J9Qm3Kf9To8fT2/SccEZj3w8kvldWdNKTSEoPdsjH8KiGX20Bc8aBzrrQHNBi1Tbw== X-Received: by 2002:a17:902:a60d:b0:186:61f6:d7f4 with SMTP id u13-20020a170902a60d00b0018661f6d7f4mr37042665plq.75.1666841542726; Wed, 26 Oct 2022 20:32:22 -0700 (PDT) Received: from localhost.localdomain ([2402:7500:47a:8591:f9eb:aa62:7d76:f953]) by smtp.gmail.com with ESMTPSA id o11-20020a65458b000000b0043c732e1536sm65921pgq.45.2022.10.26.20.32.18 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Wed, 26 Oct 2022 20:32:21 -0700 (PDT) From: cy_huang To: lee@kernel.org Cc: matthias.bgg@gmail.com, gene_chen@richtek.com, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, linux-kernel@vger.kernel.org, ChiYuan Huang , stable@vger.kernel.org Subject: [PATCH v3] mfd: mt6360: add boundary check in in mt6360 regmap read/write Date: Thu, 27 Oct 2022 11:32:09 +0800 Message-Id: <1666841529-12781-1-git-send-email-u0084500@gmail.com> X-Mailer: git-send-email 2.7.4 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20221026_203228_958123_9669FA93 X-CRM114-Status: GOOD ( 13.26 ) X-BeenThere: linux-mediatek@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-mediatek" Errors-To: linux-mediatek-bounces+linux-mediatek=archiver.kernel.org@lists.infradead.org From: ChiYuan Huang Fix the potential risk if virtual bank index is over the maximum. Refer to the discussion list on mt6370. https://lore.kernel.org/all/20220914013345.GA5802@cyhuang-hp-elitebook-840-g3.rt/ If not to check the boundary, there is also the same issue on mt6360. For mt6360 register virtual mapping, the normal range is 0 to 0x3FF. Below's the backtrace in my experiment to access mt6360 0x400 register with regmap_raw_read() and regmap_raw_write() function. 1) regmap_raw_read() Unable to handle kernel execute from non-executable memory at virtual address ffffffd4940c4c20 pc : platform_bus+0x8/0x2e8 lr : i2c_smbus_xfer+0x60/0x120 Call trace: platform_bus+0x8/0x2e8 i2c_smbus_read_i2c_block_data+0x74/0xc0 mt6360_regmap_read+0x9c/0x180 [mt6360_core] _regmap_raw_read+0xe4/0x278 regmap_raw_read+0xec/0x240 2) regmap_raw_write() Unable to handle kernel execute from non-executable memory at virtual address ffffffe4a0ac4c20 pc : platform_bus+0x8/0x2e8 lr : i2c_smbus_xfer+0x60/0x120 Call trace: platform_bus+0x8/0x2e8 i2c_smbus_write_i2c_block_data+0x84/0xd0 mt6360_regmap_write+0xa8/0x150 [mt6360_core] _regmap_raw_write_impl+0x6e8/0x828 _regmap_raw_write+0xb4/0x130 regmap_raw_write+0x74/0xb0 After adding the boundary check, the above two cases can be solved. Fixes: 3b0850440a06c (mfd: mt6360: Merge different sub-devices I2C read/write) Cc: stable@vger.kernel.org Signed-off-by: ChiYuan Huang --- Since v3: - Add backtrace log to help understanding what the potential risk is. Since v2: - Assign i2c bank variable after bank index is already checked. --- drivers/mfd/mt6360-core.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) diff --git a/drivers/mfd/mt6360-core.c b/drivers/mfd/mt6360-core.c index 6eaa677..d3b32eb 100644 --- a/drivers/mfd/mt6360-core.c +++ b/drivers/mfd/mt6360-core.c @@ -402,7 +402,7 @@ static int mt6360_regmap_read(void *context, const void *reg, size_t reg_size, struct mt6360_ddata *ddata = context; u8 bank = *(u8 *)reg; u8 reg_addr = *(u8 *)(reg + 1); - struct i2c_client *i2c = ddata->i2c[bank]; + struct i2c_client *i2c; bool crc_needed = false; u8 *buf; int buf_len = MT6360_ALLOC_READ_SIZE(val_size); @@ -410,6 +410,11 @@ static int mt6360_regmap_read(void *context, const void *reg, size_t reg_size, u8 crc; int ret; + if (bank >= MT6360_SLAVE_MAX) + return -EINVAL; + + i2c = ddata->i2c[bank]; + if (bank == MT6360_SLAVE_PMIC || bank == MT6360_SLAVE_LDO) { crc_needed = true; ret = mt6360_xlate_pmicldo_addr(®_addr, val_size); @@ -453,13 +458,18 @@ static int mt6360_regmap_write(void *context, const void *val, size_t val_size) struct mt6360_ddata *ddata = context; u8 bank = *(u8 *)val; u8 reg_addr = *(u8 *)(val + 1); - struct i2c_client *i2c = ddata->i2c[bank]; + struct i2c_client *i2c; bool crc_needed = false; u8 *buf; int buf_len = MT6360_ALLOC_WRITE_SIZE(val_size); int write_size = val_size - MT6360_REGMAP_REG_BYTE_SIZE; int ret; + if (bank >= MT6360_SLAVE_MAX) + return -EINVAL; + + i2c = ddata->i2c[bank]; + if (bank == MT6360_SLAVE_PMIC || bank == MT6360_SLAVE_LDO) { crc_needed = true; ret = mt6360_xlate_pmicldo_addr(®_addr, val_size - MT6360_REGMAP_REG_BYTE_SIZE);