From patchwork Mon Sep 28 08:55:00 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michael Walle X-Patchwork-Id: 11803169 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id DC57C6CA for ; Mon, 28 Sep 2020 08:56:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AFE1320E65 for ; Mon, 28 Sep 2020 08:56:00 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=walle.cc header.i=@walle.cc header.b="OSFBGaOB" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726518AbgI1I4A (ORCPT ); Mon, 28 Sep 2020 04:56:00 -0400 Received: from ssl.serverraum.org ([176.9.125.105]:38875 "EHLO ssl.serverraum.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726440AbgI1I4A (ORCPT ); Mon, 28 Sep 2020 04:56:00 -0400 X-Greylist: delayed 4175 seconds by postgrey-1.27 at vger.kernel.org; Mon, 28 Sep 2020 04:55:58 EDT Received: from mwalle01.sab.local. (unknown [213.135.10.150]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-384) server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by ssl.serverraum.org (Postfix) with ESMTPSA id 5219E23E40; Mon, 28 Sep 2020 10:55:57 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=walle.cc; s=mail2016061301; t=1601283357; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=8Okg/8vp+zzsmnCMZvYIcfv0Dps7pb340pkA+BoMZ14=; b=OSFBGaOBXCXoCneOqm+6YrgMT7OUsnN62YMJ/yMfKvhH5NiKM3tlWApDfOJz2v71FEcvgS s2BFw0+cnqu5usnc2OlgMNnhB4x4UWAPUrfLCnS/9MKChDz6WlW2F37oCWAUUREeI6uZOK uzCByyB8M5zwGnGhE9PJE4Vlw6CNJzk= From: Michael Walle To: linux-spi@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Sascha Hauer , Mark Brown , Vladimir Oltean , Krzysztof Kozlowski , Michael Walle Subject: [PATCH v3] spi: fsl-dspi: fix NULL pointer dereference Date: Mon, 28 Sep 2020 10:55:00 +0200 Message-Id: <20200928085500.28254-1-michael@walle.cc> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-spi@vger.kernel.org Since commit 530b5affc675 ("spi: fsl-dspi: fix use-after-free in remove path") this driver causes a kernel oops: [ 1.891065] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000080 [..] [ 2.056973] Call trace: [ 2.059425] dspi_setup+0xc8/0x2e0 [ 2.062837] spi_setup+0xcc/0x248 [ 2.066160] spi_add_device+0xb4/0x198 [ 2.069918] of_register_spi_device+0x250/0x370 [ 2.074462] spi_register_controller+0x4f4/0x770 [ 2.079094] dspi_probe+0x5bc/0x7b0 [ 2.082594] platform_drv_probe+0x5c/0xb0 [ 2.086615] really_probe+0xec/0x3c0 [ 2.090200] driver_probe_device+0x60/0xc0 [ 2.094308] device_driver_attach+0x7c/0x88 [ 2.098503] __driver_attach+0x60/0xe8 [ 2.102263] bus_for_each_dev+0x7c/0xd0 [ 2.106109] driver_attach+0x2c/0x38 [ 2.109692] bus_add_driver+0x194/0x1f8 [ 2.113538] driver_register+0x6c/0x128 [ 2.117385] __platform_driver_register+0x50/0x60 [ 2.122105] fsl_dspi_driver_init+0x24/0x30 [ 2.126302] do_one_initcall+0x54/0x2d0 [ 2.130149] kernel_init_freeable+0x1ec/0x258 [ 2.134520] kernel_init+0x1c/0x120 [ 2.138018] ret_from_fork+0x10/0x34 [ 2.141606] Code: 97e0b11d aa0003f3 b4000680 f94006e0 (f9404000) [ 2.147723] ---[ end trace 26cf63e6cbba33a8 ]--- This is because since this commit, the allocation of the drivers private data is done explicitly and in this case spi_alloc_master() won't set the correct pointer. Also move the platform_set_drvdata() to have both next to each other. Fixes: 530b5affc675 ("spi: fsl-dspi: fix use-after-free in remove path") Signed-off-by: Michael Walle Tested-by: Sascha Hauer Reviewed-by: Krzysztof Kozlowski --- changes since v2: - trimmed the commit message, suggested by Krzysztof. changes since v1: - moved platform_set_drvdata(), suggested by Krzysztof. drivers/spi/spi-fsl-dspi.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/spi/spi-fsl-dspi.c b/drivers/spi/spi-fsl-dspi.c index a939618f5e47..3967afa465f0 100644 --- a/drivers/spi/spi-fsl-dspi.c +++ b/drivers/spi/spi-fsl-dspi.c @@ -1236,6 +1236,9 @@ static int dspi_probe(struct platform_device *pdev) if (!ctlr) return -ENOMEM; + spi_controller_set_devdata(ctlr, dspi); + platform_set_drvdata(pdev, dspi); + dspi->pdev = pdev; dspi->ctlr = ctlr; @@ -1371,8 +1374,6 @@ static int dspi_probe(struct platform_device *pdev) if (dspi->devtype_data->trans_mode != DSPI_DMA_MODE) ctlr->ptp_sts_supported = true; - platform_set_drvdata(pdev, dspi); - ret = spi_register_controller(ctlr); if (ret != 0) { dev_err(&pdev->dev, "Problem registering DSPI ctlr\n");