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 8D873EE0202 for ; Wed, 13 Sep 2023 18:50:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231977AbjIMSuT (ORCPT ); Wed, 13 Sep 2023 14:50:19 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45718 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231964AbjIMSuR (ORCPT ); Wed, 13 Sep 2023 14:50:17 -0400 X-Greylist: delayed 8052 seconds by postgrey-1.37 at lindbergh.monkeyblade.net; Wed, 13 Sep 2023 11:50:12 PDT Received: from 2.mo583.mail-out.ovh.net (2.mo583.mail-out.ovh.net [178.33.109.111]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8DDE0170F for ; Wed, 13 Sep 2023 11:50:12 -0700 (PDT) Received: from director10.ghost.mail-out.ovh.net (unknown [10.108.20.179]) by mo583.mail-out.ovh.net (Postfix) with ESMTP id 846FA26A8A for ; Wed, 13 Sep 2023 14:01:41 +0000 (UTC) Received: from ghost-submission-6684bf9d7b-4l8ct (unknown [10.110.103.155]) by director10.ghost.mail-out.ovh.net (Postfix) with ESMTPS id C63AD1FE5E; Wed, 13 Sep 2023 14:01:40 +0000 (UTC) Received: from RCM-web5.webmail.mail.ovh.net ([51.255.71.60]) by ghost-submission-6684bf9d7b-4l8ct with ESMTPSA id b1tEL8TAAWUJJggAtgw5mw (envelope-from ); Wed, 13 Sep 2023 14:01:40 +0000 MIME-Version: 1.0 Date: Wed, 13 Sep 2023 17:01:40 +0300 From: =?UTF-8?Q?Jos=C3=A9_Pekkarinen?= To: Maxime Ripard Cc: airlied@gmail.com, daniel@ffwll.ch, christian.koenig@amd.com, dakr@redhat.com, boris.brezillon@collabora.com, alexander.deucher@amd.com, arthurgrillo@riseup.net, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, linux-kernel-mentees@lists.linuxfoundation.org Subject: Re: [PATCH] drm/tests: provide exit function In-Reply-To: <63yq44aikrrymqz5e5mg5mwwnaetud7sdxju2lgtsupq52b7hm@fydwmsm4yh54> References: <20230913083223.28684-1-jose.pekkarinen@foxhound.fi> <63yq44aikrrymqz5e5mg5mwwnaetud7sdxju2lgtsupq52b7hm@fydwmsm4yh54> User-Agent: Roundcube Webmail/1.4.13 Message-ID: <46d60d7e69c470e9550a2e7b7c750f12@foxhound.fi> X-Sender: jose.pekkarinen@foxhound.fi Organization: Foxhound Ltd. X-Originating-IP: 162.247.72.199 X-Webmail-UserID: jose.pekkarinen@foxhound.fi Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Ovh-Tracer-Id: 13890508628495083174 X-VR-SPAMSTATE: OK X-VR-SPAMSCORE: -100 X-VR-SPAMCAUSE: gggruggvucftvghtrhhoucdtuddrgedviedrudeikedgjedvucetufdoteggodetrfdotffvucfrrhhofhhilhgvmecuqfggjfdpvefjgfevmfevgfenuceurghilhhouhhtmecuhedttdenucesvcftvggtihhpihgvnhhtshculddquddttddmnecujfgurhepggffhffvvefujghffgfkgihoihgtgfesthekjhdttderjeenucfhrhhomheplfhoshorucfrvghkkhgrrhhinhgvnhcuoehjohhsvgdrphgvkhhkrghrihhnvghnsehfohighhhouhhnugdrfhhiqeenucggtffrrghtthgvrhhnpeekhfeguddufeegvdelgedtvdffgeehvddtkeevkeejvedvgeeitdefleehtdeitdenucfkphepuddvjedrtddrtddruddpudeivddrvdegjedrjedvrdduleelpdehuddrvdehhedrjedurdeitdenucevlhhushhtvghrufhiiigvpedtnecurfgrrhgrmhepihhnvghtpeduvdejrddtrddtrddupdhmrghilhhfrhhomhepoehjohhsvgdrphgvkhhkrghrihhnvghnsehfohighhhouhhnugdrfhhiqedpnhgspghrtghpthhtohepuddprhgtphhtthhopehlihhnuhigqdhkvghrnhgvlhesvhhgvghrrdhkvghrnhgvlhdrohhrghdpoffvtefjohhsthepmhhoheekfedpmhhouggvpehsmhhtphhouhht Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2023-09-13 12:50, Maxime Ripard wrote: > Hi, > > On Wed, Sep 13, 2023 at 11:32:23AM +0300, José Pekkarinen wrote: >> Running drm_exec_test by modprobing the module I >> observe the following output: >> >> [ 424.471936] KTAP version 1 >> [ 424.471942] 1..1 >> [ 424.472446] KTAP version 1 >> [ 424.472450] # Subtest: drm_exec >> [ 424.472453] # module: drm_exec_test >> [ 424.472459] 1..7 >> [ 424.479082] >> ================================================================== >> [ 424.479095] BUG: KASAN: slab-use-after-free in >> drm_dev_put.part.0+0x4b/0x90 [drm] >> [ 424.479426] Read of size 8 at addr ffff888132d3e028 by task >> kunit_try_catch/1866 >> [ 424.479436] >> [ 424.479442] CPU: 1 PID: 1866 Comm: kunit_try_catch Tainted: G >> N 6.6.0-rc1-dirty #2 > > That's suspicious > >> [ 424.479446] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), >> BIOS 0.0.0 02/06/2015 >> [ 424.479446] Call Trace: >> [ 424.479446] >> [ 424.479446] dump_stack_lvl+0x43/0x60 >> [ 424.479446] print_report+0xcf/0x660 >> [ 424.479446] ? __virt_addr_valid+0xd9/0x160 >> [ 424.479446] ? drm_dev_put.part.0+0x4b/0x90 [drm] >> [ 424.479446] kasan_report+0xda/0x110 >> [ 424.479446] ? drm_dev_put.part.0+0x4b/0x90 [drm] >> [ 424.479446] drm_dev_put.part.0+0x4b/0x90 [drm] >> [ 424.479446] release_nodes+0x83/0x160 >> [ 424.479446] devres_release_all+0xe6/0x130 >> [ 424.479446] ? __pfx_devres_release_all+0x10/0x10 >> [ 424.479446] ? mutex_unlock+0x80/0xd0 >> [ 424.479446] ? __pfx_mutex_unlock+0x10/0x10 >> [ 424.479446] device_unbind_cleanup+0x16/0xc0 >> [ 424.479446] device_release_driver_internal+0x28b/0x2e0 >> [ 424.479446] bus_remove_device+0x124/0x1d0 >> [ 424.479446] device_del+0x23d/0x580 >> [ 424.479446] ? __pfx_device_del+0x10/0x10 >> [ 424.479446] ? kasan_set_track+0x21/0x30 >> [ 424.479446] ? _raw_spin_lock_irqsave+0x98/0xf0 >> [ 424.479446] platform_device_del.part.0+0x19/0xe0 >> [ 424.479446] kunit_remove_resource+0xfa/0x140 [kunit] >> [ 424.479446] kunit_cleanup+0x47/0xa0 [kunit] >> [ 424.479446] ? __pfx_kunit_try_run_case_cleanup+0x10/0x10 [kunit] >> [ 424.479446] ? __pfx_kunit_generic_run_threadfn_adapter+0x10/0x10 >> [kunit] >> [ 424.479446] kunit_generic_run_threadfn_adapter+0x29/0x50 [kunit] >> [ 424.479446] kthread+0x184/0x1c0 >> [ 424.479446] ? __pfx_kthread+0x10/0x10 >> [ 424.479446] ret_from_fork+0x30/0x50 >> [ 424.479446] ? __pfx_kthread+0x10/0x10 >> [ 424.479446] ret_from_fork_asm+0x1b/0x30 >> [ 424.479446] >> [ 424.479446] >> [ 424.479446] Allocated by task 1865: >> [ 424.479446] kasan_save_stack+0x2f/0x50 >> [ 424.479446] kasan_set_track+0x21/0x30 >> [ 424.479446] __kasan_kmalloc+0xa6/0xb0 >> [ 424.479446] __kmalloc+0x5d/0x160 >> [ 424.479446] kunit_kmalloc_array+0x1c/0x50 [kunit] >> [ 424.479446] drm_exec_test_init+0xef/0x260 [drm_exec_test] >> [ 424.479446] kunit_try_run_case+0x6e/0x100 [kunit] >> [ 424.479446] kunit_generic_run_threadfn_adapter+0x29/0x50 [kunit] >> [ 424.479446] kthread+0x184/0x1c0 >> [ 424.479446] ret_from_fork+0x30/0x50 >> [ 424.479446] ret_from_fork_asm+0x1b/0x30 >> [ 424.479446] >> [ 424.479446] Freed by task 1866: >> [ 424.479446] kasan_save_stack+0x2f/0x50 >> [ 424.479446] kasan_set_track+0x21/0x30 >> [ 424.479446] kasan_save_free_info+0x27/0x40 >> [ 424.479446] ____kasan_slab_free+0x166/0x1c0 >> [ 424.479446] slab_free_freelist_hook+0x9f/0x1e0 >> [ 424.479446] __kmem_cache_free+0x187/0x2d0 >> [ 424.479446] kunit_remove_resource+0xfa/0x140 [kunit] >> [ 424.479446] kunit_cleanup+0x47/0xa0 [kunit] >> [ 424.479446] kunit_generic_run_threadfn_adapter+0x29/0x50 [kunit] >> [ 424.479446] kthread+0x184/0x1c0 >> [ 424.479446] ret_from_fork+0x30/0x50 >> [ 424.479446] ret_from_fork_asm+0x1b/0x30 >> [ 424.479446] >> [ 424.479446] The buggy address belongs to the object at >> ffff888132d3e000 >> [ 424.479446] which belongs to the cache kmalloc-256 of size 256 >> [ 424.479446] The buggy address is located 40 bytes inside of >> [ 424.479446] freed 256-byte region [ffff888132d3e000, >> ffff888132d3e100) >> [ 424.479446] >> [ 424.479446] The buggy address belongs to the physical page: >> [ 424.479446] page:0000000092ff6551 refcount:1 mapcount:0 >> mapping:0000000000000000 index:0xffff888132d3f600 pfn:0x132d3c >> [ 424.479446] head:0000000092ff6551 order:2 entire_mapcount:0 >> nr_pages_mapped:0 pincount:0 >> [ 424.479446] ksm flags: >> 0x17ffffc0000840(slab|head|node=0|zone=2|lastcpupid=0x1fffff) >> [ 424.479446] page_type: 0xffffffff() >> [ 424.479446] raw: 0017ffffc0000840 ffff888100042b40 ffffea00042c8000 >> dead000000000003 >> [ 424.479446] raw: ffff888132d3f600 000000008020001f 00000001ffffffff >> 0000000000000000 >> [ 424.479446] page dumped because: kasan: bad access detected >> [ 424.479446] >> [ 424.479446] Memory state around the buggy address: >> [ 424.479446] ffff888132d3df00: fc fc fc fc fc fc fc fc fc fc fc fc >> fc fc fc fc >> [ 424.479446] ffff888132d3df80: fc fc fc fc fc fc fc fc fc fc fc fc >> fc fc fc fc >> [ 424.479446] >ffff888132d3e000: fa fb fb fb fb fb fb fb fb fb fb fb >> fb fb fb fb >> [ 424.479446] ^ >> [ 424.479446] ffff888132d3e080: fb fb fb fb fb fb fb fb fb fb fb fb >> fb fb fb fb >> [ 424.479446] ffff888132d3e100: fc fc fc fc fc fc fc fc fc fc fc fc >> fc fc fc fc >> [ 424.479446] >> ================================================================== >> [ 424.481686] Disabling lock debugging due to kernel taint >> [ 424.484124] not ok 1 sanitycheck >> [ 424.492981] ok 2 test_lock >> [ 424.503610] ok 3 test_lock_unlock >> [ 424.515058] ok 4 test_duplicates >> [ 424.530453] ok 5 test_prepare >> [ 424.539099] ok 6 test_prepare_array >> [ 424.550730] ok 7 test_multiple_loops >> [ 424.550743] # drm_exec: pass:6 fail:1 skip:0 total:7 >> [ 424.550750] # Totals: pass:6 fail:1 skip:0 total:7 >> [ 424.550756] not ok 5 drm_exec >> >> The ouptut suggest the init function is allocating a drm_device >> that is not being freed. This patch provides the function and >> add it to the kunit_suite to produce the following result of >> the test: >> >> [ 3363.342560] KTAP version 1 >> [ 3363.342571] 1..1 >> [ 3363.343090] KTAP version 1 >> [ 3363.343095] # Subtest: drm_exec >> [ 3363.343098] # module: drm_exec_test >> [ 3363.343103] 1..7 >> [ 3363.353659] ok 1 sanitycheck >> [ 3363.364281] ok 2 test_lock >> [ 3363.375616] ok 3 test_lock_unlock >> [ 3363.388741] ok 4 test_duplicates >> [ 3363.402544] ok 5 test_prepare >> [ 3363.413163] ok 6 test_prepare_array >> [ 3363.424614] ok 7 test_multiple_loops >> [ 3363.424630] # drm_exec: pass:7 fail:0 skip:0 total:7 >> [ 3363.424637] # Totals: pass:7 fail:0 skip:0 total:7 >> [ 3363.424643] ok 1 drm_exec >> >> Signed-off-by: José Pekkarinen >> --- >> drivers/gpu/drm/tests/drm_exec_test.c | 14 ++++++++++++++ >> 1 file changed, 14 insertions(+) >> >> diff --git a/drivers/gpu/drm/tests/drm_exec_test.c >> b/drivers/gpu/drm/tests/drm_exec_test.c >> index 563949d777dd..7ff6bc6467d4 100644 >> --- a/drivers/gpu/drm/tests/drm_exec_test.c >> +++ b/drivers/gpu/drm/tests/drm_exec_test.c >> @@ -42,6 +42,19 @@ static int drm_exec_test_init(struct kunit *test) >> return 0; >> } >> >> +static void drm_exec_test_exit(struct kunit *test) >> +{ >> + struct drm_exec_priv *priv = test->priv; >> + >> + drm_kunit_helper_free_device(test, priv->dev); >> + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, priv->dev); > > This shouldn't be necessary at all since 4f2b0b583baa. Reading this suggested patch I see only references to platform_driver_unregister, platform_device_put, and platform_device_del, not the ones used in this patch. Thanks! José.