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 674BAC433EF for ; Mon, 18 Apr 2022 06:24:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229565AbiDRG1K (ORCPT ); Mon, 18 Apr 2022 02:27:10 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36396 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234301AbiDRG1F (ORCPT ); Mon, 18 Apr 2022 02:27:05 -0400 Received: from alexa-out-sd-02.qualcomm.com (alexa-out-sd-02.qualcomm.com [199.106.114.39]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7058818B2F; Sun, 17 Apr 2022 23:24:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=quicinc.com; i=@quicinc.com; q=dns/txt; s=qcdkim; t=1650263067; x=1681799067; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=tNRYDpEsRiA6xjeaEbDZJT5OooHO5zK9cBV4KUdNxW0=; b=O6phgXL/MRy0XiU9NTopaTd8SEYvlrpUKlXH8nMrl+FWXd3jZC/3U1dx ITHtmW9/kK1fOr3kwGQ85ZOvxtd9F+IDrdfqxDGpyRijkzZ8i1O2JEuqz UYb7ZhnpvhJGr6TjeSF5M3GyecQKTaxuncFkNLQmPIl9OdNL+F2tXmB+U 0=; Received: from unknown (HELO ironmsg04-sd.qualcomm.com) ([10.53.140.144]) by alexa-out-sd-02.qualcomm.com with ESMTP; 17 Apr 2022 23:24:27 -0700 X-QCInternal: smtphost Received: from unknown (HELO nasanex01a.na.qualcomm.com) ([10.52.223.231]) by ironmsg04-sd.qualcomm.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 17 Apr 2022 23:24:26 -0700 Received: from [10.201.2.159] (10.80.80.8) by nasanex01a.na.qualcomm.com (10.52.223.231) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.986.22; Sun, 17 Apr 2022 23:24:22 -0700 Message-ID: Date: Mon, 18 Apr 2022 11:54:19 +0530 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.8.0 Subject: Re: [PATCH V3] mtd: rawnand: qcom: fix memory corruption that causes panic Content-Language: en-US To: Manivannan Sadhasivam CC: , , , , , , , , References: <1650259141-20923-1-git-send-email-quic_mdalam@quicinc.com> <20220418053024.GA7431@thinkpad> From: Md Sadre Alam In-Reply-To: <20220418053024.GA7431@thinkpad> Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 8bit X-Originating-IP: [10.80.80.8] X-ClientProxiedBy: nasanex01a.na.qualcomm.com (10.52.223.231) To nasanex01a.na.qualcomm.com (10.52.223.231) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 4/18/2022 11:00 AM, Manivannan Sadhasivam wrote: > On Mon, Apr 18, 2022 at 10:49:01AM +0530, Md Sadre Alam wrote: >> This patch fixes a memory corruption that occurred in the >> nand_scan() path for Hynix nand device. >> >> On boot, for Hynix nand device will panic at a weird place: >> | Unable to handle kernel NULL pointer dereference at virtual >> address 00000070 >> | [00000070] *pgd=00000000 >> | Internal error: Oops: 5 [#1] PREEMPT SMP ARM >> | Modules linked in: >> | CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.17.0-01473-g13ae1769cfb0 >> #38 >> | Hardware name: Generic DT based system >> | PC is at nandc_set_reg+0x8/0x1c >> | LR is at qcom_nandc_command+0x20c/0x5d0 >> | pc : [] lr : [] psr: 00000113 >> | sp : c14adc50 ip : c14ee208 fp : c0cc970c >> | r10: 000000a3 r9 : 00000000 r8 : 00000040 >> | r7 : c16f6a00 r6 : 00000090 r5 : 00000004 r4 :c14ee040 >> | r3 : 00000000 r2 : 0000000b r1 : 00000000 r0 :c14ee040 >> | Flags: nzcv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none >> | Control: 10c5387d Table: 8020406a DAC: 00000051 >> | Register r0 information: slab kmalloc-2k start c14ee000 pointer offset >> 64 size 2048 >> | Process swapper/0 (pid: 1, stack limit = 0x(ptrval)) >> | nandc_set_reg from qcom_nandc_command+0x20c/0x5d0 >> | qcom_nandc_command from nand_readid_op+0x198/0x1e8 >> | nand_readid_op from hynix_nand_has_valid_jedecid+0x30/0x78 >> | hynix_nand_has_valid_jedecid from hynix_nand_init+0xb8/0x454 >> | hynix_nand_init from nand_scan_with_ids+0xa30/0x14a8 >> | nand_scan_with_ids from qcom_nandc_probe+0x648/0x7b0 >> | qcom_nandc_probe from platform_probe+0x58/0xac >> >> The problem is that the nand_scan()'s qcom_nand_attach_chip callback >> is updating the nandc->max_cwperpage from 1 to 4.This causes the >> sg_init_table of clear_bam_transaction() in the driver's >> qcom_nandc_command() to memset much more than what was initially >> allocated by alloc_bam_transaction(). >> >> This patch will update nandc->max_cwperpage 1 to 4 after nand_scan() >> returns, and remove updating nandc->max_cwperpage from >> qcom_nand_attach_chip call back. > The above statement is still wrong.    Updated in V4 patch. > >> Cc: stable@vger.kernel.org >> Fixes: 6a3cec64f18c ("mtd: rawnand: qcom: convert driver to nand_scan()") >> Reported-by: Konrad Dybcio >> Signed-off-by: Md Sadre Alam >> Signed-off-by: Sricharan R >> --- >> [V3] >> * Updated commit message Fixes, Cc, Reported-by > Missing the previous changelogs.   Updated in V4 patch. > > Thanks, > Mani > >> drivers/mtd/nand/raw/qcom_nandc.c | 24 +++++++++++++----------- >> 1 file changed, 13 insertions(+), 11 deletions(-) >> >> diff --git a/drivers/mtd/nand/raw/qcom_nandc.c b/drivers/mtd/nand/raw/qcom_nandc.c >> index 1a77542..048b255 100644 >> --- a/drivers/mtd/nand/raw/qcom_nandc.c >> +++ b/drivers/mtd/nand/raw/qcom_nandc.c >> @@ -2651,10 +2651,23 @@ static int qcom_nand_attach_chip(struct nand_chip *chip) >> ecc->engine_type = NAND_ECC_ENGINE_TYPE_ON_HOST; >> >> mtd_set_ooblayout(mtd, &qcom_nand_ooblayout_ops); >> + /* Free the initially allocated BAM transaction for reading the ONFI params */ >> + if (nandc->props->is_bam) >> + free_bam_transaction(nandc); >> >> nandc->max_cwperpage = max_t(unsigned int, nandc->max_cwperpage, >> cwperpage); >> >> + /* Now allocate the BAM transaction based on updated max_cwperpage */ >> + if (nandc->props->is_bam) { >> + nandc->bam_txn = alloc_bam_transaction(nandc); >> + if (!nandc->bam_txn) { >> + dev_err(nandc->dev, >> + "failed to allocate bam transaction\n"); >> + return -ENOMEM; >> + } >> + } >> + >> /* >> * DATA_UD_BYTES varies based on whether the read/write command protects >> * spare data with ECC too. We protect spare data by default, so we set >> @@ -2955,17 +2968,6 @@ static int qcom_nand_host_init_and_register(struct qcom_nand_controller *nandc, >> if (ret) >> return ret; >> >> - if (nandc->props->is_bam) { >> - free_bam_transaction(nandc); >> - nandc->bam_txn = alloc_bam_transaction(nandc); >> - if (!nandc->bam_txn) { >> - dev_err(nandc->dev, >> - "failed to allocate bam transaction\n"); >> - nand_cleanup(chip); >> - return -ENOMEM; >> - } >> - } >> - >> ret = mtd_device_parse_register(mtd, probes, NULL, NULL, 0); >> if (ret) >> nand_cleanup(chip); >> -- >> 2.7.4 >>