From patchwork Fri Oct 15 07:46:54 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Miles Chen X-Patchwork-Id: 12560313 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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id AA3BFC433F5 for ; Fri, 15 Oct 2021 07:47:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 796BF60EFF for ; Fri, 15 Oct 2021 07:47:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236250AbhJOHtL (ORCPT ); Fri, 15 Oct 2021 03:49:11 -0400 Received: from mailgw01.mediatek.com ([60.244.123.138]:53752 "EHLO mailgw01.mediatek.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S236189AbhJOHtK (ORCPT ); Fri, 15 Oct 2021 03:49:10 -0400 X-UUID: 05ed2bd979fb409e8f18a2e2c1abac70-20211015 X-UUID: 05ed2bd979fb409e8f18a2e2c1abac70-20211015 Received: from mtkcas10.mediatek.inc [(172.21.101.39)] by mailgw01.mediatek.com (envelope-from ) (Generic MTA with TLSv1.2 ECDHE-RSA-AES256-SHA384 256/256) with ESMTP id 1879725155; Fri, 15 Oct 2021 15:46:57 +0800 Received: from mtkcas11.mediatek.inc (172.21.101.40) by mtkmbs10n2.mediatek.inc (172.21.101.183) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384) id 15.2.792.3; Fri, 15 Oct 2021 15:46:55 +0800 Received: from mtksdccf07.mediatek.inc (172.21.84.99) by mtkcas11.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1497.2 via Frontend Transport; Fri, 15 Oct 2021 15:46:55 +0800 From: Miles Chen To: "James E . J . Bottomley" , "Martin K . Petersen" , Matthias Brugger , "Bart Van Assche" , Martin Kepplinger CC: , , , , , Miles Chen , "Stanley Chu" Subject: [PATCH] scsi: sd: fix crashes in sd_resume_runtime Date: Fri, 15 Oct 2021 15:46:54 +0800 Message-ID: <20211015074654.19615-1-miles.chen@mediatek.com> X-Mailer: git-send-email 2.18.0 MIME-Version: 1.0 X-MTK: N Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org After merging commit ed4246d37f3b ("scsi: sd: REQUEST SENSE for BLIST_IGN_MEDIA_CHANGE devices in runtime_resume()"), I hit the following crash on my device. static int sd_resume_runtime(struct device *dev) { struct scsi_disk *sdkp = dev_get_drvdata(dev); struct scsi_device *sdp = sdkp->device; // sdkp == NULL and crash if (sdp->ignore_media_change) { ... } I checked sd_resume() and found that sdkp is possbile to be NULL, and there is a null pointer test in sd_resume() for this case. To fix this crash, follow sd_resume() to test if sdkp is NULL before dereferencing it. Crash: [ 4.695171][ T151] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000008 [ 4.696591][ T151] Mem abort info: [ 4.697919][ T151] ESR = 0x96000005 [ 4.699692][ T151] EC = 0x25: DABT (current EL), IL = 32 bits [ 4.701990][ T151] SET = 0, FnV = 0 [ 4.702513][ T151] EA = 0, S1PTW = 0 [ 4.704431][ T151] FSC = 0x05: level 1 translation fault [ 4.705254][ T151] Data abort info: [ 4.705806][ T151] ISV = 0, ISS = 0x00000005 [ 4.706484][ T151] CM = 0, WnR = 0 [ 4.707048][ T151] [0000000000000008] user address but active_mm is swapper [ 4.710577][ T151] Internal error: Oops: 96000005 [#1] PREEMPT SMP [ 4.832361][ T151] Kernel Offset: 0x12acc80000 from 0xffffffc010000000 [ 4.833254][ T151] PHYS_OFFSET: 0x40000000 [ 4.833814][ T151] pstate: 80400005 (Nzcv daif +PAN -UAO) [ 4.834546][ T151] pc : sd_resume_runtime+0x20/0x14c [ 4.835227][ T151] lr : scsi_runtime_resume+0x84/0xe4 [ 4.835916][ T151] sp : ffffffc0110db8d0 [ 4.836450][ T151] x29: ffffffc0110db8d0 x28: 0000000000000001 [ 4.837258][ T151] x27: ffffff80c0bd1ac0 x26: ffffff80c0bd1ad0 [ 4.838063][ T151] x25: ffffff80cea7e448 x24: ffffffd2bf961000 [ 4.838867][ T151] x23: ffffffd2be69f838 x22: ffffffd2bd9dfb4c [ 4.839670][ T151] x21: 0000000000000000 x20: ffffff80cea7e000 [ 4.840474][ T151] x19: ffffff80cea7e260 x18: ffffffc0110dd078 [ 4.841277][ T151] x17: 00000000658783d9 x16: 0000000051469dac [ 4.842081][ T151] x15: 00000000b87f6327 x14: 0000000068fd680d [ 4.842885][ T151] x13: ffffff80c0bd2470 x12: ffffffd2bfa7f5f0 [ 4.843688][ T151] x11: 0000000000000078 x10: 0000000000000001 [ 4.844492][ T151] x9 : 00000000000000b1 x8 : ffffffd2be69f88c [ 4.845295][ T151] x7 : ffffffd2bd9e0e5c x6 : 0000000000000000 [ 4.846099][ T151] x5 : 0000000000000080 x4 : 0000000000000001 [ 4.846902][ T151] x3 : 68fd680dfe4ebe5e x2 : 0000000000000003 [ 4.847706][ T151] x1 : ffffffd2bf7f9380 x0 : ffffff80cea7e260 [ 4.856708][ T151] die+0x16c/0x59c [ 4.857191][ T151] __do_kernel_fault+0x1e8/0x210 [ 4.857833][ T151] do_page_fault+0xa4/0x654 [ 4.858418][ T151] do_translation_fault+0x6c/0x1b0 [ 4.859083][ T151] do_mem_abort+0x68/0x10c [ 4.859655][ T151] el1_abort+0x40/0x64 [ 4.860182][ T151] el1h_64_sync_handler+0x54/0x88 [ 4.860834][ T151] el1h_64_sync+0x7c/0x80 [ 4.861395][ T151] sd_resume_runtime+0x20/0x14c [ 4.862025][ T151] scsi_runtime_resume+0x84/0xe4 [ 4.862667][ T151] __rpm_callback+0x1f4/0x8cc [ 4.863275][ T151] rpm_resume+0x7e8/0xaa4 [ 4.863836][ T151] __pm_runtime_resume+0xa0/0x110 [ 4.864489][ T151] sd_probe+0x30/0x428 [ 4.865016][ T151] really_probe+0x14c/0x500 [ 4.865602][ T151] __driver_probe_device+0xb4/0x18c [ 4.866278][ T151] driver_probe_device+0x60/0x2c4 [ 4.866931][ T151] __device_attach_driver+0x228/0x2bc [ 4.867630][ T151] __device_attach_async_helper+0x154/0x21c [ 4.868398][ T151] async_run_entry_fn+0x5c/0x1c4 [ 4.869038][ T151] process_one_work+0x3ac/0x590 [ 4.869670][ T151] worker_thread+0x320/0x758 [ 4.870265][ T151] kthread+0x2e8/0x35c [ 4.870792][ T151] ret_from_fork+0x10/0x20 Cc: Stanley Chu Fixes: ed4246d37f3b ("scsi: sd: REQUEST SENSE for BLIST_IGN_MEDIA_CHANGE devices in runtime_resume()") Signed-off-by: Miles Chen Reviewed-by: Martin Kepplinger Reviewed-by: Stanley Chu --- drivers/scsi/sd.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c index 523bf2fdc253..fce63335084e 100644 --- a/drivers/scsi/sd.c +++ b/drivers/scsi/sd.c @@ -3683,7 +3683,12 @@ static int sd_resume(struct device *dev) static int sd_resume_runtime(struct device *dev) { struct scsi_disk *sdkp = dev_get_drvdata(dev); - struct scsi_device *sdp = sdkp->device; + struct scsi_device *sdp; + + if (!sdkp) /* E.g.: runtime resume at the start of sd_probe() */ + return 0; + + sdp = sdkp->device; if (sdp->ignore_media_change) { /* clear the device's sense data */