From patchwork Mon Sep 28 08:32:38 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michael Walle X-Patchwork-Id: 11803129 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 EA7C1139A for ; Mon, 28 Sep 2020 08:32:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C2176207E8 for ; Mon, 28 Sep 2020 08:32:48 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=walle.cc header.i=@walle.cc header.b="gluXADIn" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726458AbgI1Ics (ORCPT ); Mon, 28 Sep 2020 04:32:48 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41188 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726440AbgI1Ics (ORCPT ); Mon, 28 Sep 2020 04:32:48 -0400 Received: from ssl.serverraum.org (ssl.serverraum.org [IPv6:2a01:4f8:151:8464::1:2]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CBDE6C0613CE; Mon, 28 Sep 2020 01:32:47 -0700 (PDT) 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 A2B9723E40; Mon, 28 Sep 2020 10:32:45 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=walle.cc; s=mail2016061301; t=1601281966; 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=84nf58r4xfqTwvxmnC0LUvWYNLFQ3GSFYprQkKFhSqI=; b=gluXADInXin5bmV70jihLsfY0tV16qLmrz3jGsppU9+j064Gk8CGdIADcdW8o6QamrE92B lweLrYiOp3FPnPFZ2cwa40pkHRT7Tq24A1VGAmg0Ehd6jFF4dE/Ebl4d1YgstXPRlFFnbp IQ6JmsbI96aVnDHNN/x8uZgr5ZmpGs0= 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 v2] spi: fsl-dspi: fix NULL pointer dereference Date: Mon, 28 Sep 2020 10:32:38 +0200 Message-Id: <20200928083238.27137-1-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 [ 1.899889] Mem abort info: [ 1.902692] ESR = 0x96000004 [ 1.905754] EC = 0x25: DABT (current EL), IL = 32 bits [ 1.911089] SET = 0, FnV = 0 [ 1.914156] EA = 0, S1PTW = 0 [ 1.917303] Data abort info: [ 1.920193] ISV = 0, ISS = 0x00000004 [ 1.924044] CM = 0, WnR = 0 [ 1.927022] [0000000000000080] user address but active_mm is swapper [ 1.933403] Internal error: Oops: 96000004 [#1] PREEMPT SMP [ 1.938995] Modules linked in: [ 1.942060] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.9.0-rc6-next-20200925-00026-gae556cc74e28-dirty #94 [ 1.951838] Hardware name: Kontron SMARC-sAL28 (Single PHY) on SMARC Eval 2.0 carrier (DT) [ 1.960135] pstate: 40000005 (nZcv daif -PAN -UAO -TCO BTYPE=--) [ 1.966168] pc : dspi_setup+0xc8/0x2e0 [ 1.969926] lr : dspi_setup+0xbc/0x2e0 [ 1.973684] sp : ffff80001139b930 [ 1.977005] x29: ffff80001139b930 x28: ffff00207a5d2000 [ 1.982338] x27: 0000000000000006 x26: ffff00207a44d410 [ 1.987669] x25: ffff002079c08100 x24: ffff00207a5d2400 [ 1.993000] x23: ffff00207a5d2600 x22: ffff800011169948 [ 1.998332] x21: ffff800010cbcd20 x20: ffff00207a58a800 [ 2.003663] x19: ffff00207a76b700 x18: 0000000000000010 [ 2.008994] x17: 0000000000000001 x16: 0000000000000019 [ 2.014326] x15: ffffffffffffffff x14: 0720072007200720 [ 2.019657] x13: 0720072007200720 x12: ffff8000111fc5e0 [ 2.024989] x11: 0000000000000003 x10: ffff8000111e45a0 [ 2.030320] x9 : 0000000000000000 x8 : ffff00207a76b780 [ 2.035651] x7 : 0000000000000000 x6 : 000000000000003f [ 2.040982] x5 : 0000000000000040 x4 : ffff80001139b918 [ 2.046313] x3 : 0000000000000001 x2 : 64b62cc917af5100 [ 2.051643] x1 : 0000000000000000 x0 : 0000000000000000 [ 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 ]--- [ 2.152374] Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b [ 2.160061] SMP: stopping secondary CPUs [ 2.163999] Kernel Offset: disabled [ 2.167496] CPU features: 0x0040022,20006008 [ 2.171777] Memory Limit: none [ 2.174840] ---[ end Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b ]--- 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 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");