From patchwork Fri Oct 4 12:37:38 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thadeu Lima de Souza Cascardo X-Patchwork-Id: 13822247 Received: from fanzine2.igalia.com (fanzine.igalia.com [178.60.130.6]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 25F161FAA for ; Fri, 4 Oct 2024 12:37:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=178.60.130.6 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728045477; cv=none; b=Zz1MNaoo36cERh1hOnBFoVXsxKnKa0Qq0lJUTjLW8vj+1Z997BR5KcYFvR98VS7C0XRkJEdpm5kow2Sf8iyOVPEUG9dca2KiafcTKUoxCCXPQF1k5uiw2ex1vW7DBvUxo/9mRey1oVulWIjXonHlwrTRxGmpTULfztbR9C1HXIE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728045477; c=relaxed/simple; bh=cBThrvn7cUpqvBpHMZdHj4wqW8U2af6g7bHp1BCzVrg=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=o58Wg43ctPHlUi5uZiKuV/RApUOS1wgw8LVl3ycpUMmZwn+mfR8WS+DH/HgX7abyf0vIalXIfIFzYkPIBCLgRIV/ILEOliJn9xrl0U9iy67sro+QwAi4RlnNqy4jgrPKqRq2SeW5nobVqCmeqe2sZ1lAqiRW+M2YSoPCeuWRDvc= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=igalia.com; spf=pass smtp.mailfrom=igalia.com; dkim=pass (2048-bit key) header.d=igalia.com header.i=@igalia.com header.b=Lxb7EDHf; arc=none smtp.client-ip=178.60.130.6 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=igalia.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=igalia.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=igalia.com header.i=@igalia.com header.b="Lxb7EDHf" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=igalia.com; s=20170329; h=Content-Transfer-Encoding:MIME-Version:Message-Id:Date:Subject: Cc:To:From:Sender:Reply-To:Content-Type:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: In-Reply-To:References:List-Id:List-Help:List-Unsubscribe:List-Subscribe: List-Post:List-Owner:List-Archive; bh=uUeD04e+m0NiIp0aVnMQuYhHmOwr4AhKfU0daa/SHNc=; b=Lxb7EDHfqqdbMHpTiXptHO2Yuk WWVa7FMyeQbZ3wXMxGdVTPZF0a+FxrjXO+/jzPyCcAiPgPNOdZT0e5kaeGDutTAcUdii0ysTv6GiE QwkOxVenNe0+Sc/qVlcg98niyacPCNPubeczYhdwkRUXUzSNZ+b0Wau0s0qs7TdnC0c7xMV2r4YVy VB3Q7PQtsgDBX79YjI4sRqmFnsjgPXeqPxcPgvfn+OMCZ4Nl8hz/TVbTJ1vdg5x5tHT3eMrYD9a7y Agt9z12QoO/7xej/Y6DkgaEb7Oo30suMn1ryXW58TUghggthMQPv7Gvt2VDn4rhvzGbgmtjZJ9E7n 9ZjaZxUA==; Received: from 179-125-71-238-dinamico.pombonet.net.br ([179.125.71.238] helo=quatroqueijos.lan) by fanzine2.igalia.com with esmtpsa (Cipher TLS1.3:ECDHE_X25519__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim) id 1swhZ3-004pgT-Tq; Fri, 04 Oct 2024 14:37:46 +0200 From: Thadeu Lima de Souza Cascardo To: linux-usb@vger.kernel.org Cc: Greg Kroah-Hartman , Heikki Krogerus , kernel-dev@igalia.com, Thadeu Lima de Souza Cascardo Subject: [PATCH] usb: typec: altmode should keep reference to parent Date: Fri, 4 Oct 2024 09:37:38 -0300 Message-Id: <20241004123738.2964524-1-cascardo@igalia.com> X-Mailer: git-send-email 2.34.1 Precedence: bulk X-Mailing-List: linux-usb@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 The altmode device release refers to its parent device, but without keeping a reference to it. When registering the altmode, get a reference to the parent and put it in the release function. Before this fix, when using CONFIG_DEBUG_KOBJECT_RELEASE, we see issues like this: [ 43.572860] kobject: 'port0.0' (ffff8880057ba008): kobject_release, parent 0000000000000000 (delayed 3000) [ 43.573532] kobject: 'port0.1' (ffff8880057bd008): kobject_release, parent 0000000000000000 (delayed 1000) [ 43.574407] kobject: 'port0' (ffff8880057b9008): kobject_release, parent 0000000000000000 (delayed 3000) [ 43.575059] kobject: 'port1.0' (ffff8880057ca008): kobject_release, parent 0000000000000000 (delayed 4000) [ 43.575908] kobject: 'port1.1' (ffff8880057c9008): kobject_release, parent 0000000000000000 (delayed 4000) [ 43.576908] kobject: 'typec' (ffff8880062dbc00): kobject_release, parent 0000000000000000 (delayed 4000) [ 43.577769] kobject: 'port1' (ffff8880057bf008): kobject_release, parent 0000000000000000 (delayed 3000) [ 46.612867] ================================================================== [ 46.613402] BUG: KASAN: slab-use-after-free in typec_altmode_release+0x38/0x129 [ 46.614003] Read of size 8 at addr ffff8880057b9118 by task kworker/2:1/48 [ 46.614538] [ 46.614668] CPU: 2 UID: 0 PID: 48 Comm: kworker/2:1 Not tainted 6.12.0-rc1-00138-gedbae730ad31 #535 [ 46.615391] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.15.0-1 04/01/2014 [ 46.616042] Workqueue: events kobject_delayed_cleanup [ 46.616446] Call Trace: [ 46.616648] [ 46.616820] dump_stack_lvl+0x5b/0x7c [ 46.617112] ? typec_altmode_release+0x38/0x129 [ 46.617470] print_report+0x14c/0x49e [ 46.617769] ? rcu_read_unlock_sched+0x56/0x69 [ 46.618117] ? __virt_addr_valid+0x19a/0x1ab [ 46.618456] ? kmem_cache_debug_flags+0xc/0x1d [ 46.618807] ? typec_altmode_release+0x38/0x129 [ 46.619161] kasan_report+0x8d/0xb4 [ 46.619447] ? typec_altmode_release+0x38/0x129 [ 46.619809] ? process_scheduled_works+0x3cb/0x85f [ 46.620185] typec_altmode_release+0x38/0x129 [ 46.620537] ? process_scheduled_works+0x3cb/0x85f [ 46.620907] device_release+0xaf/0xf2 [ 46.621206] kobject_delayed_cleanup+0x13b/0x17a [ 46.621584] process_scheduled_works+0x4f6/0x85f [ 46.621955] ? __pfx_process_scheduled_works+0x10/0x10 [ 46.622353] ? hlock_class+0x31/0x9a [ 46.622647] ? lock_acquired+0x361/0x3c3 [ 46.622956] ? move_linked_works+0x46/0x7d [ 46.623277] worker_thread+0x1ce/0x291 [ 46.623582] ? __kthread_parkme+0xc8/0xdf [ 46.623900] ? __pfx_worker_thread+0x10/0x10 [ 46.624236] kthread+0x17e/0x190 [ 46.624501] ? kthread+0xfb/0x190 [ 46.624756] ? __pfx_kthread+0x10/0x10 [ 46.625015] ret_from_fork+0x20/0x40 [ 46.625268] ? __pfx_kthread+0x10/0x10 [ 46.625532] ret_from_fork_asm+0x1a/0x30 [ 46.625805] [ 46.625953] [ 46.626056] Allocated by task 678: [ 46.626287] kasan_save_stack+0x24/0x44 [ 46.626555] kasan_save_track+0x14/0x2d [ 46.626811] __kasan_kmalloc+0x3f/0x4d [ 46.627049] __kmalloc_noprof+0x1bf/0x1f0 [ 46.627362] typec_register_port+0x23/0x491 [ 46.627698] cros_typec_probe+0x634/0xbb6 [ 46.628026] platform_probe+0x47/0x8c [ 46.628311] really_probe+0x20a/0x47d [ 46.628605] device_driver_attach+0x39/0x72 [ 46.628940] bind_store+0x87/0xd7 [ 46.629213] kernfs_fop_write_iter+0x1aa/0x218 [ 46.629574] vfs_write+0x1d6/0x29b [ 46.629856] ksys_write+0xcd/0x13b [ 46.630128] do_syscall_64+0xd4/0x139 [ 46.630420] entry_SYSCALL_64_after_hwframe+0x76/0x7e [ 46.630820] [ 46.630946] Freed by task 48: [ 46.631182] kasan_save_stack+0x24/0x44 [ 46.631493] kasan_save_track+0x14/0x2d [ 46.631799] kasan_save_free_info+0x3f/0x4d [ 46.632144] __kasan_slab_free+0x37/0x45 [ 46.632474] kfree+0x1d4/0x252 [ 46.632725] device_release+0xaf/0xf2 [ 46.633017] kobject_delayed_cleanup+0x13b/0x17a [ 46.633388] process_scheduled_works+0x4f6/0x85f [ 46.633764] worker_thread+0x1ce/0x291 [ 46.634065] kthread+0x17e/0x190 [ 46.634324] ret_from_fork+0x20/0x40 [ 46.634621] ret_from_fork_asm+0x1a/0x30 Fixes: 8a37d87d72f0 ("usb: typec: Bus type for alternate modes") Signed-off-by: Thadeu Lima de Souza Cascardo Reviewed-by: Dmitry Baryshkov Reviewed-by: Heikki Krogerus --- drivers/usb/typec/class.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/usb/typec/class.c b/drivers/usb/typec/class.c index 9262fcd4144f..d61b4c74648d 100644 --- a/drivers/usb/typec/class.c +++ b/drivers/usb/typec/class.c @@ -519,6 +519,7 @@ static void typec_altmode_release(struct device *dev) typec_altmode_put_partner(alt); altmode_id_remove(alt->adev.dev.parent, alt->id); + put_device(alt->adev.dev.parent); kfree(alt); } @@ -568,6 +569,8 @@ typec_register_altmode(struct device *parent, alt->adev.dev.type = &typec_altmode_dev_type; dev_set_name(&alt->adev.dev, "%s.%u", dev_name(parent), id); + get_device(alt->adev.dev.parent); + /* Link partners and plugs with the ports */ if (!is_port) typec_altmode_set_partner(alt);