From nobody Sun Feb 8 11:07:06 2026 Received: from mx0a-0064b401.pphosted.com (mx0a-0064b401.pphosted.com [205.220.166.238]) (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 58DDE3D76; Wed, 9 Apr 2025 08:32:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=205.220.166.238 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744187565; cv=none; b=M7wpbdYxSAnru2hSSK9V8EFT7XjqhUyTFC7kdoTms+WOzRbCZhktHlINe9g/jN5JmRU5gY6Gq4DFd6fXtBKFS9WZAB/E3sygEtx7nUhUQ6IvFs6PNSnTIjDrWxP8w5JnI0AlgtysWPnljcjA9r2eyR+R3FZNPGtEUeKTT5HOHpI= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744187565; c=relaxed/simple; bh=06i03/eW88kNMSyIQpnLFojEQBRVBRiIZ5NKVcOuDbQ=; h=From:To:CC:Subject:Date:Message-ID:MIME-Version:Content-Type; b=b2qM1u3K1xf2XBr663HwvV0oRHMqv8pAfzF9Kbz75BUBYXdyiP4UIcrWYWqP1k7XwxoXn0K3zM08wmPzE0GRWQwC5Nqf8Kdkv4sbKzP2ZdU8Gx5HulsIpS9Xqw7tepiGHP9Wbs5kwg5praLN5MNIYMg62xGVbNTR8IPCJrAX6aA= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=windriver.com; spf=pass smtp.mailfrom=windriver.com; arc=none smtp.client-ip=205.220.166.238 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=windriver.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=windriver.com Received: from pps.filterd (m0250810.ppops.net [127.0.0.1]) by mx0a-0064b401.pphosted.com (8.18.1.2/8.18.1.2) with ESMTP id 53960GmG025473; Wed, 9 Apr 2025 01:32:32 -0700 Received: from ala-exchng02.corp.ad.wrs.com (ala-exchng02.wrs.com [147.11.82.254]) by mx0a-0064b401.pphosted.com (PPS) with ESMTPS id 45tyt4cxqa-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT); Wed, 09 Apr 2025 01:32:31 -0700 (PDT) Received: from ALA-EXCHNG02.corp.ad.wrs.com (147.11.82.254) by ALA-EXCHNG02.corp.ad.wrs.com (147.11.82.254) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.43; Wed, 9 Apr 2025 01:32:30 -0700 Received: from pek-lpd-ccm5.wrs.com (147.11.136.210) by ALA-EXCHNG02.corp.ad.wrs.com (147.11.82.254) with Microsoft SMTP Server id 15.1.2507.43 via Frontend Transport; Wed, 9 Apr 2025 01:32:29 -0700 From: Yun Zhou To: , , CC: , Subject: [PATCH] clk: fix slab-use-after-free when clk_core_populate_parent_map failed Date: Wed, 9 Apr 2025 16:32:28 +0800 Message-ID: <20250409083228.2944917-1-yun.zhou@windriver.com> X-Mailer: git-send-email 2.27.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Proofpoint-ORIG-GUID: coc-3x-werZjsYlDDhKWyece3W9ZaQKf X-Authority-Analysis: v=2.4 cv=RMSzH5i+ c=1 sm=1 tr=0 ts=67f6309f cx=c_pps a=K4BcnWQioVPsTJd46EJO2w==:117 a=K4BcnWQioVPsTJd46EJO2w==:17 a=XR8D0OoHHMoA:10 a=t7CeM3EgAAAA:8 a=eLMzZ2F9_icGV3DWmJ0A:9 a=FdTzh2GWekK77mhwV6Dw:22 X-Proofpoint-GUID: coc-3x-werZjsYlDDhKWyece3W9ZaQKf X-Sensitive_Customer_Information: Yes X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1095,Hydra:6.0.680,FMLib:17.12.68.34 definitions=2025-04-09_03,2025-04-08_04,2024-11-22_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 phishscore=0 impostorscore=0 lowpriorityscore=0 mlxscore=0 malwarescore=0 suspectscore=0 mlxlogscore=999 spamscore=0 priorityscore=1501 adultscore=0 clxscore=1011 bulkscore=0 classifier=spam authscore=0 authtc=n/a authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.21.0-2502280000 definitions=main-2504090042 Content-Type: text/plain; charset="utf-8" If clk_core_populate_parent_map() fails, core->parents will be immediately released within clk_core_populate_parent_map(). Therefore it is can't be released in __clk_release() again. This fixes the following KASAN reported issue: =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D BUG: KASAN: slab-use-after-free in __clk_release+0x80/0x160 Read of size 8 at addr ffffff8043fd0980 by task kworker/u6:0/27 CPU: 1 PID: 27 Comm: kworker/u6:0 Tainted: G W 6.6.69-yocto= -standard+ #7 Hardware name: Raspberry Pi 4 Model B (DT) Workqueue: events_unbound deferred_probe_work_func Call trace: dump_backtrace+0x98/0xf8 show_stack+0x20/0x38 dump_stack_lvl+0x48/0x60 print_report+0xf8/0x5d8 kasan_report+0xb4/0x100 __asan_load8+0x9c/0xc0 __clk_release+0x80/0x160 __clk_register+0x6dc/0xfb8 devm_clk_hw_register+0x70/0x108 bcm2835_register_clock+0x284/0x358 bcm2835_clk_probe+0x2c4/0x438 platform_probe+0x98/0x110 really_probe+0x1e4/0x3e8 __driver_probe_device+0xc0/0x1a0 driver_probe_device+0x110/0x1e8 __device_attach_driver+0xf0/0x1a8 bus_for_each_drv+0xf8/0x178 __device_attach+0x120/0x240 device_initial_probe+0x1c/0x30 bus_probe_device+0xdc/0xe8 deferred_probe_work_func+0xe8/0x130 process_one_work+0x2a4/0x698 worker_thread+0x53c/0x708 kthread+0x1b4/0x1c8 ret_from_fork+0x10/0x20 Allocated by task 27: kasan_save_stack+0x3c/0x68 kasan_set_track+0x2c/0x40 kasan_save_alloc_info+0x24/0x38 __kasan_kmalloc+0xd4/0xd8 __kmalloc+0x74/0x238 __clk_register+0x718/0xfb8 devm_clk_hw_register+0x70/0x108 bcm2835_register_clock+0x284/0x358 bcm2835_clk_probe+0x2c4/0x438 platform_probe+0x98/0x110 really_probe+0x1e4/0x3e8 __driver_probe_device+0xc0/0x1a0 driver_probe_device+0x110/0x1e8 __device_attach_driver+0xf0/0x1a8 bus_for_each_drv+0xf8/0x178 __device_attach+0x120/0x240 device_initial_probe+0x1c/0x30 bus_probe_device+0xdc/0xe8 deferred_probe_work_func+0xe8/0x130 process_one_work+0x2a4/0x698 worker_thread+0x53c/0x708 kthread+0x1b4/0x1c8 ret_from_fork+0x10/0x20 Freed by task 27: kasan_save_stack+0x3c/0x68 kasan_set_track+0x2c/0x40 kasan_save_free_info+0x38/0x60 __kasan_slab_free+0x100/0x170 slab_free_freelist_hook+0xcc/0x218 __kmem_cache_free+0x158/0x210 kfree+0x88/0x140 __clk_register+0x9d0/0xfb8 devm_clk_hw_register+0x70/0x108 bcm2835_register_clock+0x284/0x358 bcm2835_clk_probe+0x2c4/0x438 platform_probe+0x98/0x110 really_probe+0x1e4/0x3e8 __driver_probe_device+0xc0/0x1a0 driver_probe_device+0x110/0x1e8 __device_attach_driver+0xf0/0x1a8 bus_for_each_drv+0xf8/0x178 __device_attach+0x120/0x240 device_initial_probe+0x1c/0x30 bus_probe_device+0xdc/0xe8 deferred_probe_work_func+0xe8/0x130 process_one_work+0x2a4/0x698 worker_thread+0x53c/0x708 kthread+0x1b4/0x1c8 ret_from_fork+0x10/0x20 The buggy address belongs to the object at ffffff8043fd0800 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 384 bytes inside of freed 512-byte region [ffffff8043fd0800, ffffff8043fd0a00) The buggy address belongs to the physical page: page:fffffffe010ff400 refcount:1 mapcount:0 mapping:0000000000000000 index:= 0xffffff8043fd0e00 pfn:0x43fd0 head:fffffffe010ff400 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0x4000000000000840(slab|head|zone=3D1) page_type: 0xffffffff() raw: 4000000000000840 ffffff8040002f40 ffffff8040000a50 ffffff8040000a50 raw: ffffff8043fd0e00 0000000000150002 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffffff8043fd0880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffffff8043fd0900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffffff8043fd0980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffffff8043fd0a00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffffff8043fd0a80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D Fixes: 9d05ae531c2c ("clk: Initialize struct clk_core kref earlier") Signed-off-by: Yun Zhou --- drivers/clk/clk.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c index 0565c87656cf..3f89ed51d4a4 100644 --- a/drivers/clk/clk.c +++ b/drivers/clk/clk.c @@ -4242,7 +4242,6 @@ static int clk_core_populate_parent_map(struct clk_co= re *core, * having a cache of names/clk_hw pointers to clk_core pointers. */ parents =3D kcalloc(num_parents, sizeof(*parents), GFP_KERNEL); - core->parents =3D parents; if (!parents) return -ENOMEM; =20 @@ -4283,6 +4282,8 @@ static int clk_core_populate_parent_map(struct clk_co= re *core, } } =20 + core->parents =3D parents; + return 0; } =20 @@ -4290,7 +4291,7 @@ static void clk_core_free_parent_map(struct clk_core = *core) { int i =3D core->num_parents; =20 - if (!core->num_parents) + if (!core->parents) return; =20 while (--i >=3D 0) { --=20 2.27.0