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=-10.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,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 547EAC56202 for ; Fri, 20 Nov 2020 21:21:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EDE3F2240B for ; Fri, 20 Nov 2020 21:21:48 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="rNubP2Br" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728761AbgKTVV2 (ORCPT ); Fri, 20 Nov 2020 16:21:28 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40014 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728349AbgKTVV1 (ORCPT ); Fri, 20 Nov 2020 16:21:27 -0500 Received: from mail-qk1-x733.google.com (mail-qk1-x733.google.com [IPv6:2607:f8b0:4864:20::733]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4C0B8C0613CF for ; Fri, 20 Nov 2020 13:21:27 -0800 (PST) Received: by mail-qk1-x733.google.com with SMTP id l2so10391307qkf.0 for ; Fri, 20 Nov 2020 13:21:27 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=jV6GL0Q5YRUAwzjPbGXYfFacZG8+1GCXNpjb7n5NcnY=; b=rNubP2BrxqlSe54C2d64q8xXgnsf5PRaEUIqT2SE3cN4oFfUkiYHPiiNhxJcTXEFxc CR5M8jXZ13zkbeFJmizi5rKqi7XOIPJC0bDJce/iPctmpjxVlOV0VwjeGNSuAwEE/32i AvXrl7gnFWgCmFQ0qXy59FqrHKrhwcGXmSmno2uon+R7ueStTU3FidoneLIEL3VdhdwR QgZvlWPX066I4CbV6sOLuqlwyBwGQ7VN5ZRfChH00ddqf9qJnsIw17PFpv3nV7LuL8tj A5aefh++p9knRPeT37hinyFowKGSxH4YiBJldA44FasWbd7M0HsVS1bf6efqoOYu07dz PX1A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=jV6GL0Q5YRUAwzjPbGXYfFacZG8+1GCXNpjb7n5NcnY=; b=PJ5mDJurR99Ic+gneY9BgmOgJoOv/3L53Y6Os1m1nNMPkXxhlghHkP5iVxZuSAxVav wZcs5B26ljEfTfCKW7RfulGr874A7sTxyhiRYkv5qAxx/8pUhGSJqJQn5+u/2tFoedRC IyLMtKssrIABC/M8elFj7i7pCSllbLFIRffpTr+vGsiWrO/gEStsqCxzfBKOpyS1xLe1 4j+zWZfYRZEtypPqIc45QoBL4J6mV1TbTg5d0SbKbWzKTV9XFDuWimupEAPhjg6iREqN 6q1K3j7/Vw9qURHKAmdhNkLPYaygLok/9K2hi3DtOHUH8yFgWMeOt78j5QdtwYxB2dnC Ijyg== X-Gm-Message-State: AOAM531/2ozmlXWDsteemd5xu+R/eDO4qbknqC8kRI+C756TpcrEld77 vfZ1UnNNYuphmKXsR/6Qef6YW64hGPntww== X-Google-Smtp-Source: ABdhPJzblAGFYHOWlQVd5BmEKVMX0l6E/MUu5mdr0aV07Rc6q/ebrM2Lx9SQmfxZsrMRjRfKEKIxXg== X-Received: by 2002:a37:77c5:: with SMTP id s188mr19249059qkc.266.1605907285648; Fri, 20 Nov 2020 13:21:25 -0800 (PST) Received: from tong-desktop.local ([2601:5c0:c200:27c6:7d5d:36ba:87f1:dd85]) by smtp.googlemail.com with ESMTPSA id 82sm2936014qke.76.2020.11.20.13.21.24 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 20 Nov 2020 13:21:25 -0800 (PST) From: Tong Zhang To: Anders Larsen , linux-kernel@vger.kernel.org Cc: ztong0001@gmail.com Subject: [PATCH v1] qnx4_match: do not over run the buffer Date: Fri, 20 Nov 2020 16:21:20 -0500 Message-Id: <20201120212120.2502522-1-ztong0001@gmail.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org the di_fname may not terminated by '\0', use strnlen to prevent buffer overrun [ 513.248784] qnx4_readdir: bread failed (3718095557) [ 513.250880] ================================================================== [ 513.251109] BUG: KASAN: use-after-free in strlen+0x1f/0x40 [ 513.251268] Read of size 1 at addr ffff888002700000 by task find/230 [ 513.251419] [ 513.251677] CPU: 0 PID: 230 Comm: find Not tainted 5.10.0-rc4+ #64 [ 513.251805] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-48-gd84 [ 513.252069] Call Trace: [ 513.252310] dump_stack+0x7d/0xa3 [ 513.252443] print_address_description.constprop.0+0x1e/0x220 [ 513.252572] ? _raw_spin_lock_irqsave+0x7b/0xd0 [ 513.252681] ? _raw_write_lock_irqsave+0xd0/0xd0 [ 513.252785] ? strlen+0x1f/0x40 [ 513.252869] ? strlen+0x1f/0x40 [ 513.252955] kasan_report.cold+0x37/0x7c [ 513.253059] ? qnx4_block_map+0x130/0x1d0 [ 513.253152] ? strlen+0x1f/0x40 [ 513.253237] strlen+0x1f/0x40 [ 513.253329] qnx4_lookup+0xab/0x220 [ 513.253431] __lookup_slow+0x103/0x220 [ 513.253531] ? vfs_unlink+0x2e0/0x2e0 [ 513.253626] ? down_read+0xd8/0x190 [ 513.253721] ? down_write_killable+0x110/0x110 [ 513.253823] ? generic_permission+0x4c/0x240 [ 513.253929] walk_component+0x214/0x2c0 [ 513.254035] ? handle_dots.part.0+0x760/0x760 [ 513.254137] ? walk_component+0x2c0/0x2c0 [ 513.254233] ? path_init+0x546/0x6b0 [ 513.254327] ? __kernel_text_address+0x9/0x30 [ 513.254430] ? unwind_get_return_address+0x2a/0x40 [ 513.254538] ? create_prof_cpu_mask+0x20/0x20 [ 513.254637] ? arch_stack_walk+0x99/0xf0 [ 513.254736] path_lookupat.isra.0+0xb0/0x240 [ 513.254840] filename_lookup+0x128/0x250 [ 513.254939] ? may_linkat+0xb0/0xb0 [ 513.255033] ? __fput+0x199/0x3c0 [ 513.255127] ? kasan_save_stack+0x32/0x40 [ 513.255224] ? kasan_save_stack+0x1b/0x40 [ 513.255323] ? kasan_unpoison_shadow+0x33/0x40 [ 513.255426] ? __kasan_kmalloc.constprop.0+0xc2/0xd0 [ 513.255538] ? getname_flags+0x100/0x2a0 [ 513.255635] vfs_statx+0xd8/0x1d0 [ 513.255728] ? vfs_getattr+0x40/0x40 [ 513.255821] ? lockref_put_return+0xb2/0x120 [ 513.255922] __do_sys_newfstatat+0x7d/0xd0 [ 513.256022] ? __ia32_sys_newlstat+0x30/0x30 [ 513.256122] ? __kasan_slab_free+0x121/0x150 [ 513.256222] ? rcu_segcblist_enqueue+0x72/0x80 [ 513.256333] ? fpregs_assert_state_consistent+0x4d/0x60 [ 513.256446] ? exit_to_user_mode_prepare+0x2d/0xf0 [ 513.256551] ? __x64_sys_newfstatat+0x39/0x60 [ 513.256651] do_syscall_64+0x33/0x40 [ 513.256750] entry_SYSCALL_64_after_hwframe+0x44/0xa9 --- fs/qnx4/namei.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/qnx4/namei.c b/fs/qnx4/namei.c index 8d72221735d7..c0e79094f578 100644 --- a/fs/qnx4/namei.c +++ b/fs/qnx4/namei.c @@ -40,7 +40,7 @@ static int qnx4_match(int len, const char *name, } else { namelen = QNX4_SHORT_NAME_MAX; } - thislen = strlen( de->di_fname ); + thislen = strnlen( de->di_fname, QNX4_SHORT_NAME_MAX ); if ( thislen > namelen ) thislen = namelen; if (len != thislen) { -- 2.25.1