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 9AD64C433FE for ; Thu, 14 Apr 2022 15:56:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1343844AbiDNPxb (ORCPT ); Thu, 14 Apr 2022 11:53:31 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59216 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1359291AbiDNPmy (ORCPT ); Thu, 14 Apr 2022 11:42:54 -0400 Received: from alexa-out.qualcomm.com (alexa-out.qualcomm.com [129.46.98.28]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 20067DFD69; Thu, 14 Apr 2022 08:30:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=quicinc.com; i=@quicinc.com; q=dns/txt; s=qcdkim; t=1649950236; x=1681486236; h=from:to:cc:subject:date:message-id; bh=7AbcbFgk7EWSyJCT0kIEs/FzXtBXjMhHceTuFImAtF0=; b=gpR+CoFVJy7FRQSxku1QYJ4M7XBn8WWMcRggb+El/GGasdlduzkLEwfe fuq7pkVIiotdyXcYqU+3MOGdtlpRbqy01DhNTyThh6I6fQt8ltfNnlxjO K5bWfvVeOEVInfbtKSoS4BxQtwWHQbBHVyIBwhm6pZvNETmXv0Dh9FmVy w=; Received: from ironmsg-lv-alpha.qualcomm.com ([10.47.202.13]) by alexa-out.qualcomm.com with ESMTP; 14 Apr 2022 08:30:36 -0700 X-QCInternal: smtphost Received: from ironmsg02-blr.qualcomm.com ([10.86.208.131]) by ironmsg-lv-alpha.qualcomm.com with ESMTP/TLS/AES256-SHA; 14 Apr 2022 08:30:34 -0700 X-QCInternal: smtphost Received: from mdalam-linux.qualcomm.com ([10.201.2.71]) by ironmsg02-blr.qualcomm.com with ESMTP; 14 Apr 2022 21:00:22 +0530 Received: by mdalam-linux.qualcomm.com (Postfix, from userid 466583) id 94F97229BE; Thu, 14 Apr 2022 21:00:21 +0530 (IST) From: Md Sadre Alam To: mani@kernel.org, miquel.raynal@bootlin.com, richard@nod.at, vigneshr@ti.com, linux-mtd@lists.infradead.org, linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org Cc: konrad.dybcio@somainline.org, quic_srichara@quicinc.com, quic_mdalam@quicinc.com Subject: [PATCH V2] mtd: rawnand: qcom: fix memory corruption that causes panic Date: Thu, 14 Apr 2022 21:00:17 +0530 Message-Id: <1649950217-32272-1-git-send-email-quic_mdalam@quicinc.com> X-Mailer: git-send-email 2.7.4 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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. Signed-off-by: Md Sadre Alam Signed-off-by: Sricharan R --- [V2] * Freed previously alloacted memory for bam txn before updating max_cwperpage inside qcom_nand_attach_chip(). * Moved alloc_bam_transaction() inside qcom_nand_attach_chip(). after upding max_cwperpage 4 or 8 based on page size. 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