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 63CA3C433FE for ; Mon, 18 Apr 2022 06:36:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230144AbiDRGjS (ORCPT ); Mon, 18 Apr 2022 02:39:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56004 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229927AbiDRGjR (ORCPT ); Mon, 18 Apr 2022 02:39:17 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6BBDB12AB7; Sun, 17 Apr 2022 23:36:39 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id BD0BB60FFA; Mon, 18 Apr 2022 06:36:38 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 70004C385A1; Mon, 18 Apr 2022 06:36:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1650263798; bh=Za6KZ/5oQI4gabmeDq3TrExMqEraIMNG5gnoCNXLvhQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=l9kFt8EZuIrUAF/JaTls8JcrDN6n+dpj4VSswl0aa+oHW0n0ojlF2NT6z9W4WFEPC qodedpLkovtWOHYeAquC0db9IExry7grpRPRbycdENe0US8DpAJrK8JnobmCjJi8zH emd6V13eDaVtwGuc44Sr8CgLafEYoz2OBgOTkolhnj6K1/rkcQVigW39bv6tqtC4Fo n0/f+lWIoRagYWa+JIOFMy0GxoWunDO+EHVrWPOtuOrAoigwo1OCElL7eN/XhaS3+z xu6E0GuRv1jrIJyjYH+EHqEmZyt2jLET4554GXxaWZp+zmCjIEW4JBJpuB5miRF/OV Wyh1oStbW05Sg== Date: Mon, 18 Apr 2022 12:06:30 +0530 From: Manivannan Sadhasivam To: Md Sadre Alam Cc: 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, konrad.dybcio@somainline.org, quic_srichara@quicinc.com, stable@vger.kernel.org Subject: Re: [PATCH V4] mtd: rawnand: qcom: fix memory corruption that causes panic Message-ID: <20220418063630.GJ7431@thinkpad> References: <1650262991-21588-1-git-send-email-quic_mdalam@quicinc.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <1650262991-21588-1-git-send-email-quic_mdalam@quicinc.com> Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org On Mon, Apr 18, 2022 at 11:53:11AM +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 or 8 based on page size. > 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 or 8 based on page > size in qcom_nand_attach_chip call back after freeing the previously > allocated memory for bam txn as per nandc->max_cwperpage = 1 and then > again allocating bam txn as per nandc->max_cwperpage = 4 or 8 based on > page size in qcom_nand_attach_chip call back itself. > > 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 I know that you and Sri were involved in creating this patch. So there should be a co-developed-by tag for Sri and your signed-off-by should be the last one. Like below, Cc: stable@vger.kernel.org Fixes: 6a3cec64f18c ("mtd: rawnand: qcom: convert driver to nand_scan()") Reported-by: Konrad Dybcio Co-developed-by: Sricharan R Signed-off-by: Sricharan R Signed-off-by: Md Sadre Alam With that, Reviewed-by: Manivannan Sadhasivam Thanks, Mani > --- > Changes in V4: > > * Incorporated "commit log wrong" comment from Mani > * Updated commit log > > Changes in V3: > > * Incorporated "Fixes tags are missing" comment from Miquèl > * Added Fixes tag Fixes:6a3cec64f18c ("mtd: rawnand: qcom: convert driver to nand_scan()") > * Incorporated "stable tag missing" comment from Miquèl > * Added stable tag Cc: stable@vger.kernel.org > * Incorporated "Reported-by tag missing" comment from Mani > * Added Reported-by tag Reported-by: Konrad Dybcio > > Changes in V2: > > * Incorporated "alloc_bam_transaction inside qcom_nand_attach_chip" suggestion from Mani > * 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 >