From patchwork Thu May 4 02:53:53 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wang Zhaolong X-Patchwork-Id: 1776688 X-Patchwork-Delegate: richard@nod.at Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; spf=none (no SPF record) smtp.mailfrom=lists.infradead.org (client-ip=2607:7c80:54:3::133; helo=bombadil.infradead.org; envelope-from=linux-mtd-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org; receiver=) Authentication-Results: legolas.ozlabs.org; dkim=pass (2048-bit key; secure) header.d=lists.infradead.org header.i=@lists.infradead.org header.a=rsa-sha256 header.s=bombadil.20210309 header.b=kKvA/oRk; dkim-atps=neutral Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:3::133]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-384) server-digest SHA384) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4QBdhL6hDZz20fg for ; Thu, 4 May 2023 12:54:42 +1000 (AEST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:Message-ID:Date:Subject:CC :To:From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References: List-Owner; bh=3Es/unQnLUnefJ5V4fcw6RLIXVArO6fMl/EOWSckOrY=; b=kKvA/oRkqr4CVI tExQ/hFqPzQqeOjZVtHM5yWsuCv4/29Ug28dR5LeZ9CJfizebkBA7HTiagb79eR9wWB3i2pZcV+3M b5uBN2pf1MLUYL/2jwEAbeKGHcxYA6bVzfrv600sj88eIqej1rBH8o5t1nFAETrJ4gsi6syj2odho FP2SwMt8CxmDnbLmUEl2rhD+AaCYvbFwqCLOdzVX0ugf3QXSN4SCXuPzUNEw36teA+gRjsMWBXt5e DCmIFEpmwsyr5njeS/6SxUXeSHl0lIuj71znWOcT1U2tzeupZiVgOjbTyH3fSH5NcLSzoVRGz0bpO 6zSR3KwFjA+/C9xplRlg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1puP6g-006Q0B-12; Thu, 04 May 2023 02:54:10 +0000 Received: from szxga02-in.huawei.com ([45.249.212.188]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1puP6a-006Py2-2d for linux-mtd@lists.infradead.org; Thu, 04 May 2023 02:54:07 +0000 Received: from dggpemm500009.china.huawei.com (unknown [172.30.72.56]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4QBdcG1cMQzLnZs; Thu, 4 May 2023 10:51:10 +0800 (CST) Received: from huawei.com (10.175.101.6) by dggpemm500009.china.huawei.com (7.185.36.225) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.23; Thu, 4 May 2023 10:53:57 +0800 From: ZhaoLong Wang To: , , CC: , , , Subject: [PATCH -next,V2 1/2] ubi: fix slab-out-of-bounds in ubi_eba_get_ldesc+0xfb/0x130 Date: Thu, 4 May 2023 10:53:53 +0800 Message-ID: <20230504025354.3595768-1-wangzhaolong1@huawei.com> X-Mailer: git-send-email 2.31.1 MIME-Version: 1.0 X-Originating-IP: [10.175.101.6] X-ClientProxiedBy: dggems701-chm.china.huawei.com (10.3.19.178) To dggpemm500009.china.huawei.com (7.185.36.225) X-CFilter-Loop: Reflected X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230503_195405_198888_D237DF45 X-CRM114-Status: GOOD ( 18.82 ) X-Spam-Score: -1.3 (-) X-Spam-Report: Spam detection software, running on the system "bombadil.infradead.org", has NOT identified this incoming email as spam. The original message has been attached to this so you can view it or label similar future email. If you have any questions, see the administrator of that system for details. Content preview: From: Guo Xuenan When using ioctl interface to resize ubi volume, ubi_resize_volume will resize eba table first, but not change vol->reserved_pebs in the same atomic context which may cause concurrency access eba tabl [...] Content analysis details: (-1.3 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -2.3 RCVD_IN_DNSWL_MED RBL: Sender listed at https://www.dnswl.org/, medium trust [45.249.212.188 listed in list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record 1.0 HEXHASH_WORD Multiple instances of word + hexadecimal hash X-BeenThere: linux-mtd@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-mtd" Errors-To: linux-mtd-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org From: Guo Xuenan When using ioctl interface to resize ubi volume, ubi_resize_volume will resize eba table first, but not change vol->reserved_pebs in the same atomic context which may cause concurrency access eba table. For example, When user do shrink ubi volume A calling ubi_resize_volume, while the other thread is writing (volume B) and triggering wear-leveling, which may calling ubi_write_fastmap, under these circumstances, KASAN may report: slab-out-of-bounds in ubi_eba_get_ldesc+0xfb/0x130. The main work of this patch include: 1. fix races in ubi_resize_volume and ubi_update_fastmap, to avoid eba_tbl read out of bounds. first, we make eba_tbl and reserved_pebs updating under the protect of vol->volumes_lock. second, rollback volume in case of resize failure. Also mention that for volume shrinking failure, since part of volume has been shrunk and unmapped, there is no need to recover {rsvd/avail}_pebs. 2. fix some memleak in error path of ubi_resize_volume when destroy new_eba_tbl. ================================================================== BUG: KASAN: slab-out-of-bounds in ubi_eba_get_ldesc+0xfb/0x130 [ubi] Read of size 4 at addr ffff88800f43f570 by task kworker/u16:0/7 CPU: 0 PID: 7 Comm: kworker/u16:0 Not tainted 5.16.0-rc7 #3 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014 Workqueue: writeback wb_workfn (flush-ubifs_0_0) Call Trace: dump_stack_lvl+0x4d/0x66 print_address_description.constprop.0+0x41/0x60 kasan_report.cold+0x83/0xdf ubi_eba_get_ldesc+0xfb/0x130 [ubi] ubi_update_fastmap.cold+0x60f/0xc7d [ubi] ubi_wl_get_peb+0x25b/0x4f0 [ubi] try_write_vid_and_data+0x9a/0x4d0 [ubi] ubi_eba_write_leb+0x7e4/0x17d0 [ubi] ubi_leb_map+0x1a0/0x2c0 [ubi] ubifs_leb_map+0x139/0x270 [ubifs] ubifs_add_bud_to_log+0xb40/0xf30 [ubifs] make_reservation+0x86e/0xb00 [ubifs] ubifs_jnl_write_data+0x430/0x9d0 [ubifs] do_writepage+0x1d1/0x550 [ubifs] ubifs_writepage+0x37c/0x670 [ubifs] __writepage+0x67/0x170 write_cache_pages+0x259/0xa90 do_writepages+0x277/0x5d0 __writeback_single_inode+0xb8/0x850 writeback_sb_inodes+0x4b3/0xb20 __writeback_inodes_wb+0xc1/0x220 wb_writeback+0x59f/0x740 wb_workfn+0x6d0/0xca0 process_one_work+0x711/0xfc0 worker_thread+0x95/0xd00 kthread+0x3a6/0x490 ret_from_fork+0x1f/0x30 Allocated by task 711: kasan_save_stack+0x1e/0x50 __kasan_kmalloc+0x81/0xa0 ubi_eba_create_table+0x88/0x1a0 [ubi] ubi_resize_volume.cold+0x175/0xae7 [ubi] ubi_cdev_ioctl+0x57f/0x1a60 [ubi] __x64_sys_ioctl+0x13a/0x1c0 do_syscall_64+0x35/0x80 entry_SYSCALL_64_after_hwframe+0x44/0xae Last potentially related work creation: kasan_save_stack+0x1e/0x50 __kasan_record_aux_stack+0xb7/0xc0 call_rcu+0xd6/0x1000 blk_stat_free_callback+0x28/0x30 blk_release_queue+0x8a/0x2e0 kobject_put+0x186/0x4c0 scsi_device_dev_release_usercontext+0x620/0xbd0 execute_in_process_context+0x2f/0x120 device_release+0xa4/0x240 kobject_put+0x186/0x4c0 put_device+0x20/0x30 __scsi_remove_device+0x1c3/0x300 scsi_probe_and_add_lun+0x2140/0x2eb0 __scsi_scan_target+0x1f2/0xbb0 scsi_scan_channel+0x11b/0x1a0 scsi_scan_host_selected+0x24c/0x310 do_scsi_scan_host+0x1e0/0x250 do_scan_async+0x45/0x490 async_run_entry_fn+0xa2/0x530 process_one_work+0x711/0xfc0 worker_thread+0x95/0xd00 kthread+0x3a6/0x490 ret_from_fork+0x1f/0x30 The buggy address belongs to the object at ffff88800f43f500 which belongs to the cache kmalloc-128 of size 128 The buggy address is located 112 bytes inside of 128-byte region [ffff88800f43f500, ffff88800f43f580) The buggy address belongs to the page: page:ffffea00003d0f00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0xf43c head:ffffea00003d0f00 order:2 compound_mapcount:0 compound_pincount:0 flags: 0x1fffff80010200(slab|head|node=0|zone=1|lastcpupid=0x1fffff) raw: 001fffff80010200 ffffea000046ba08 ffffea0000457208 ffff88810004d1c0 raw: 0000000000000000 0000000000190019 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88800f43f400: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88800f43f480: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc > ffff88800f43f500: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 fc fc ^ ffff88800f43f580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88800f43f600: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc The following steps can used to reproduce: Process 1: write and trigger ubi wear-leveling ubimkvol /dev/ubi0 -s 5000MiB -N v1 ubimkvol /dev/ubi0 -s 2000MiB -N v2 ubimkvol /dev/ubi0 -s 10MiB -N v3 mount -t ubifs /dev/ubi0_0 /mnt/ubifs while true; do filename=/mnt/ubifs/$((RANDOM)) dd if=/dev/random of=${filename} bs=1M count=$((RANDOM % 1000)) rm -rf ${filename} sync /mnt/ubifs/ done Process 2: do random resize struct ubi_rsvol_req req; req.vol_id = 1; req.bytes = (rand() % 50) * 512KB; ioctl(fd, UBI_IOCRSVOL, &req); V2: - Add volumes_lock in ubi_eba_copy_leb() to avoid race caused by updating eba_tbl. V1: - Rebase the patch on the latest mainline. Signed-off-by: Guo Xuenan Signed-off-by: ZhaoLong Wang Reviewed-by: Zhihao Cheng --- drivers/mtd/ubi/eba.c | 7 +++++++ drivers/mtd/ubi/vmt.c | 24 +++++++++++++++++------- 2 files changed, 24 insertions(+), 7 deletions(-) diff --git a/drivers/mtd/ubi/eba.c b/drivers/mtd/ubi/eba.c index 403b79d6efd5..48e6bedfc361 100644 --- a/drivers/mtd/ubi/eba.c +++ b/drivers/mtd/ubi/eba.c @@ -1450,7 +1450,14 @@ int ubi_eba_copy_leb(struct ubi_device *ubi, int from, int to, } ubi_assert(vol->eba_tbl->entries[lnum].pnum == from); + + /** + * The volumes_lock lock is needed here to prevent the expired old eba_tbl + * being updated when the eba_tbl is copied in the ubi_resize_volume() process. + */ + spin_lock(&ubi->volumes_lock); vol->eba_tbl->entries[lnum].pnum = to; + spin_unlock(&ubi->volumes_lock); out_unlock_buf: mutex_unlock(&ubi->buf_mutex); diff --git a/drivers/mtd/ubi/vmt.c b/drivers/mtd/ubi/vmt.c index 2c867d16f89f..97294def01eb 100644 --- a/drivers/mtd/ubi/vmt.c +++ b/drivers/mtd/ubi/vmt.c @@ -408,6 +408,7 @@ int ubi_resize_volume(struct ubi_volume_desc *desc, int reserved_pebs) struct ubi_device *ubi = vol->ubi; struct ubi_vtbl_record vtbl_rec; struct ubi_eba_table *new_eba_tbl = NULL; + struct ubi_eba_table *old_eba_tbl = NULL; int vol_id = vol->vol_id; if (ubi->ro_mode) @@ -453,10 +454,13 @@ int ubi_resize_volume(struct ubi_volume_desc *desc, int reserved_pebs) err = -ENOSPC; goto out_free; } + ubi->avail_pebs -= pebs; ubi->rsvd_pebs += pebs; ubi_eba_copy_table(vol, new_eba_tbl, vol->reserved_pebs); - ubi_eba_replace_table(vol, new_eba_tbl); + old_eba_tbl = vol->eba_tbl; + vol->eba_tbl = new_eba_tbl; + vol->reserved_pebs = reserved_pebs; spin_unlock(&ubi->volumes_lock); } @@ -471,7 +475,9 @@ int ubi_resize_volume(struct ubi_volume_desc *desc, int reserved_pebs) ubi->avail_pebs -= pebs; ubi_update_reserved(ubi); ubi_eba_copy_table(vol, new_eba_tbl, reserved_pebs); - ubi_eba_replace_table(vol, new_eba_tbl); + old_eba_tbl = vol->eba_tbl; + vol->eba_tbl = new_eba_tbl; + vol->reserved_pebs = reserved_pebs; spin_unlock(&ubi->volumes_lock); } @@ -493,7 +499,6 @@ int ubi_resize_volume(struct ubi_volume_desc *desc, int reserved_pebs) if (err) goto out_acc; - vol->reserved_pebs = reserved_pebs; if (vol->vol_type == UBI_DYNAMIC_VOLUME) { vol->used_ebs = reserved_pebs; vol->last_eb_bytes = vol->usable_leb_size; @@ -501,19 +506,24 @@ int ubi_resize_volume(struct ubi_volume_desc *desc, int reserved_pebs) (long long)vol->used_ebs * vol->usable_leb_size; } + /* destroy old table */ + ubi_eba_destroy_table(old_eba_tbl); ubi_volume_notify(ubi, vol, UBI_VOLUME_RESIZED); self_check_volumes(ubi); return err; out_acc: + spin_lock(&ubi->volumes_lock); + vol->reserved_pebs = reserved_pebs - pebs; if (pebs > 0) { - spin_lock(&ubi->volumes_lock); ubi->rsvd_pebs -= pebs; ubi->avail_pebs += pebs; - spin_unlock(&ubi->volumes_lock); + ubi_eba_copy_table(vol, old_eba_tbl, vol->reserved_pebs); + } else { + ubi_eba_copy_table(vol, old_eba_tbl, reserved_pebs); } - return err; - + vol->eba_tbl = old_eba_tbl; + spin_unlock(&ubi->volumes_lock); out_free: ubi_eba_destroy_table(new_eba_tbl); return err; From patchwork Thu May 4 02:53:54 2023 Content-Type: text/plain; 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Thu, 04 May 2023 02:54:09 +0000 Received: from szxga01-in.huawei.com ([45.249.212.187]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1puP6b-006Pxw-0G for linux-mtd@lists.infradead.org; Thu, 04 May 2023 02:54:06 +0000 Received: from dggpemm500009.china.huawei.com (unknown [172.30.72.55]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4QBdZp5VfMzpTRS; Thu, 4 May 2023 10:49:54 +0800 (CST) Received: from huawei.com (10.175.101.6) by dggpemm500009.china.huawei.com (7.185.36.225) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.23; Thu, 4 May 2023 10:53:57 +0800 From: ZhaoLong Wang To: , , CC: , , , Subject: [PATCH -next,V2 2/2] ubi: Correct the number of PEBs after a volume resize failure Date: Thu, 4 May 2023 10:53:54 +0800 Message-ID: <20230504025354.3595768-2-wangzhaolong1@huawei.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20230504025354.3595768-1-wangzhaolong1@huawei.com> References: <20230504025354.3595768-1-wangzhaolong1@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.101.6] X-ClientProxiedBy: dggems701-chm.china.huawei.com (10.3.19.178) To dggpemm500009.china.huawei.com (7.185.36.225) X-CFilter-Loop: Reflected X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230503_195405_288656_381B6F00 X-CRM114-Status: GOOD ( 10.54 ) X-Spam-Score: -2.3 (--) X-Spam-Report: Spam detection software, running on the system "bombadil.infradead.org", has NOT identified this incoming email as spam. The original message has been attached to this so you can view it or label similar future email. If you have any questions, see the administrator of that system for details. Content preview: In the error handing path `out_acc` of the ubi_resize_volume(), when `pebs < 0`, it means that the volume table record fails to be updated when the volume is shrinked. In this case, the number of ubi- [...] Content analysis details: (-2.3 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -2.3 RCVD_IN_DNSWL_MED RBL: Sender listed at https://www.dnswl.org/, medium trust [45.249.212.187 listed in list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record X-BeenThere: linux-mtd@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-mtd" Errors-To: linux-mtd-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org In the error handing path `out_acc` of the ubi_resize_volume(), when `pebs < 0`, it means that the volume table record fails to be updated when the volume is shrinked. In this case, the number of ubi->avail_pebs` and `ubi->rsvd_pebs` should also be restored, otherwise the UBI will display an incorrect number of available PEBs. Signed-off-by: ZhaoLong Wang Reviewed-by: Zhihao Cheng --- drivers/mtd/ubi/vmt.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) diff --git a/drivers/mtd/ubi/vmt.c b/drivers/mtd/ubi/vmt.c index 97294def01eb..990571287e84 100644 --- a/drivers/mtd/ubi/vmt.c +++ b/drivers/mtd/ubi/vmt.c @@ -515,13 +515,12 @@ int ubi_resize_volume(struct ubi_volume_desc *desc, int reserved_pebs) out_acc: spin_lock(&ubi->volumes_lock); vol->reserved_pebs = reserved_pebs - pebs; - if (pebs > 0) { - ubi->rsvd_pebs -= pebs; - ubi->avail_pebs += pebs; + ubi->rsvd_pebs -= pebs; + ubi->avail_pebs += pebs; + if (pebs > 0) ubi_eba_copy_table(vol, old_eba_tbl, vol->reserved_pebs); - } else { + else ubi_eba_copy_table(vol, old_eba_tbl, reserved_pebs); - } vol->eba_tbl = old_eba_tbl; spin_unlock(&ubi->volumes_lock); out_free: