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 X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5ED8BC433DB for ; Thu, 18 Mar 2021 03:08:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1215361584 for ; Thu, 18 Mar 2021 03:08:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230433AbhCRDHq (ORCPT ); Wed, 17 Mar 2021 23:07:46 -0400 Received: from szxga04-in.huawei.com ([45.249.212.190]:14081 "EHLO szxga04-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230192AbhCRDHQ (ORCPT ); Wed, 17 Mar 2021 23:07:16 -0400 Received: from DGGEMS403-HUB.china.huawei.com (unknown [172.30.72.59]) by szxga04-in.huawei.com (SkyGuard) with ESMTP id 4F1Bj82D5jz17MWh; Thu, 18 Mar 2021 11:05:16 +0800 (CST) Received: from DESKTOP-FKFNUOQ.china.huawei.com (10.67.101.50) by DGGEMS403-HUB.china.huawei.com (10.3.19.203) with Microsoft SMTP Server id 14.3.498.0; Thu, 18 Mar 2021 11:06:59 +0800 From: Zhe Li To: , , , CC: , , , , Subject: [PATCH] jffs2: fix kasan slab-out-of-bounds problem Date: Thu, 18 Mar 2021 11:06:57 +0800 Message-ID: <20210318030657.22840-1-lizhe67@huawei.com> X-Mailer: git-send-email 2.21.0.windows.1 MIME-Version: 1.0 Content-Transfer-Encoding: 7BIT Content-Type: text/plain; charset=US-ASCII X-Originating-IP: [10.67.101.50] X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: lizhe KASAN report a slab-out-of-bounds problem. The logs are listed below. It is because in function jffs2_scan_dirent_node, we alloc "checkedlen+1" bytes for fd->name and we check crc with length rd->nsize. If checkedlen is less than rd->nsize, it will cause the slab-out-of-bounds problem. jffs2: Dirent at *** has zeroes in name. Truncating to %d char ================================================================== BUG: KASAN: slab-out-of-bounds in crc32_le+0x1ce/0x260 at addr ffff8800842cf2d1 Read of size 1 by task test_JFFS2/915 ============================================================================= BUG kmalloc-64 (Tainted: G B O ): kasan: bad access detected ----------------------------------------------------------------------------- INFO: Allocated in jffs2_alloc_full_dirent+0x2a/0x40 age=0 cpu=1 pid=915 ___slab_alloc+0x580/0x5f0 __slab_alloc.isra.24+0x4e/0x64 __kmalloc+0x170/0x300 jffs2_alloc_full_dirent+0x2a/0x40 jffs2_scan_eraseblock+0x1ca4/0x3b64 jffs2_scan_medium+0x285/0xfe0 jffs2_do_mount_fs+0x5fb/0x1bbc jffs2_do_fill_super+0x245/0x6f0 jffs2_fill_super+0x287/0x2e0 mount_mtd_aux.isra.0+0x9a/0x144 mount_mtd+0x222/0x2f0 jffs2_mount+0x41/0x60 mount_fs+0x63/0x230 vfs_kern_mount.part.6+0x6c/0x1f4 do_mount+0xae8/0x1940 SyS_mount+0x105/0x1d0 INFO: Freed in jffs2_free_full_dirent+0x22/0x40 age=27 cpu=1 pid=915 __slab_free+0x372/0x4e4 kfree+0x1d4/0x20c jffs2_free_full_dirent+0x22/0x40 jffs2_build_remove_unlinked_inode+0x17a/0x1e4 jffs2_do_mount_fs+0x1646/0x1bbc jffs2_do_fill_super+0x245/0x6f0 jffs2_fill_super+0x287/0x2e0 mount_mtd_aux.isra.0+0x9a/0x144 mount_mtd+0x222/0x2f0 jffs2_mount+0x41/0x60 mount_fs+0x63/0x230 vfs_kern_mount.part.6+0x6c/0x1f4 do_mount+0xae8/0x1940 SyS_mount+0x105/0x1d0 entry_SYSCALL_64_fastpath+0x1e/0x97 Call Trace: [] dump_stack+0x59/0x7e [] print_trailer+0x125/0x1b0 [] object_err+0x34/0x40 [] kasan_report.part.1+0x21f/0x534 [] ? vprintk+0x2d/0x40 [] ? crc32_le+0x1ce/0x260 [] kasan_report+0x26/0x30 [] __asan_load1+0x3d/0x50 [] crc32_le+0x1ce/0x260 [] ? jffs2_alloc_full_dirent+0x2a/0x40 [] jffs2_scan_eraseblock+0x1d0c/0x3b64 [] ? jffs2_scan_medium+0xccf/0xfe0 [] ? jffs2_scan_make_ino_cache+0x14c/0x14c [] ? kasan_unpoison_shadow+0x35/0x50 [] ? kasan_unpoison_shadow+0x35/0x50 [] ? kasan_kmalloc+0x5e/0x70 [] ? kmem_cache_alloc_trace+0x10c/0x2cc [] ? mtd_point+0xf7/0x130 [] jffs2_scan_medium+0x285/0xfe0 [] ? jffs2_scan_eraseblock+0x3b64/0x3b64 [] ? kasan_unpoison_shadow+0x35/0x50 [] ? kasan_unpoison_shadow+0x35/0x50 [] ? kasan_kmalloc+0x5e/0x70 [] ? __kmalloc+0x12b/0x300 [] ? kasan_kmalloc+0x5e/0x70 [] ? jffs2_sum_init+0x9f/0x240 [] jffs2_do_mount_fs+0x5fb/0x1bbc [] ? jffs2_del_noinode_dirent+0x640/0x640 [] ? kasan_kmalloc+0x5e/0x70 [] ? __init_rwsem+0x97/0xac [] jffs2_do_fill_super+0x245/0x6f0 [] jffs2_fill_super+0x287/0x2e0 [] ? jffs2_parse_options+0x594/0x594 [] mount_mtd_aux.isra.0+0x9a/0x144 [] mount_mtd+0x222/0x2f0 [] ? jffs2_parse_options+0x594/0x594 [] ? mount_mtd_aux.isra.0+0x144/0x144 [] ? free_pages+0x13/0x1c [] ? selinux_sb_copy_data+0x278/0x2e0 [] jffs2_mount+0x41/0x60 [] mount_fs+0x63/0x230 [] ? alloc_vfsmnt+0x32f/0x3b0 [] vfs_kern_mount.part.6+0x6c/0x1f4 [] do_mount+0xae8/0x1940 [] ? audit_filter_rules.constprop.6+0x1d10/0x1d10 [] ? copy_mount_string+0x40/0x40 [] ? alloc_pages_current+0xa4/0x1bc [] ? __get_free_pages+0x25/0x50 [] ? copy_mount_options.part.17+0x183/0x264 [] SyS_mount+0x105/0x1d0 [] ? copy_mnt_ns+0x560/0x560 [] ? msa_space_switch_handler+0x13d/0x190 [] entry_SYSCALL_64_fastpath+0x1e/0x97 [] ? msa_space_switch+0xb0/0xe0 Memory state around the buggy address: ffff8800842cf180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8800842cf200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8800842cf280: fc fc fc fc fc fc 00 00 00 00 01 fc fc fc fc fc ^ ffff8800842cf300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8800842cf380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ================================================================== Reported-by: Kunkun Xu Signed-off-by: lizhe --- fs/jffs2/scan.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/jffs2/scan.c b/fs/jffs2/scan.c index db72a9d..b676056 100644 --- a/fs/jffs2/scan.c +++ b/fs/jffs2/scan.c @@ -1079,7 +1079,7 @@ static int jffs2_scan_dirent_node(struct jffs2_sb_info *c, struct jffs2_eraseblo memcpy(&fd->name, rd->name, checkedlen); fd->name[checkedlen] = 0; - crc = crc32(0, fd->name, rd->nsize); + crc = crc32(0, fd->name, checkedlen); if (crc != je32_to_cpu(rd->name_crc)) { pr_notice("%s(): Name CRC failed on node at 0x%08x: Read 0x%08x, calculated 0x%08x\n", __func__, ofs, je32_to_cpu(rd->name_crc), crc); -- 2.7.4