From patchwork Wed Oct 13 03:39:12 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "yebin (H)" X-Patchwork-Id: 12554395 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 41270C433FE for ; Wed, 13 Oct 2021 03:26:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2497B61027 for ; Wed, 13 Oct 2021 03:26:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237415AbhJMD2i (ORCPT ); Tue, 12 Oct 2021 23:28:38 -0400 Received: from szxga02-in.huawei.com ([45.249.212.188]:23372 "EHLO szxga02-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229526AbhJMD2f (ORCPT ); Tue, 12 Oct 2021 23:28:35 -0400 Received: from dggeme754-chm.china.huawei.com (unknown [172.30.72.56]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4HTdB3515Vzbd19; Wed, 13 Oct 2021 11:22:03 +0800 (CST) Received: from huawei.com (10.175.127.227) by dggeme754-chm.china.huawei.com (10.3.19.100) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2308.8; Wed, 13 Oct 2021 11:26:31 +0800 From: Ye Bin To: , , , , , CC: Ye Bin Subject: [PATCH v2 resend 1/2] scsi:scsi_debug: Fix out-of-bound read in resp_readcap16 Date: Wed, 13 Oct 2021 11:39:12 +0800 Message-ID: <20211013033913.2551004-2-yebin10@huawei.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20211013033913.2551004-1-yebin10@huawei.com> References: <20211013033913.2551004-1-yebin10@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.127.227] X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) To dggeme754-chm.china.huawei.com (10.3.19.100) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org We got following warning when runing syzkaller: [ 3813.830724] sg_write: data in/out 65466/242 bytes for SCSI command 0x9e-- guessing data in; [ 3813.830724] program syz-executor not setting count and/or reply_len properly [ 3813.836956] ================================================================== [ 3813.839465] BUG: KASAN: stack-out-of-bounds in sg_copy_buffer+0x157/0x1e0 [ 3813.841773] Read of size 4096 at addr ffff8883cf80f540 by task syz-executor/1549 [ 3813.846612] Call Trace: [ 3813.846995] dump_stack+0x108/0x15f [ 3813.847524] print_address_description+0xa5/0x372 [ 3813.848243] kasan_report.cold+0x236/0x2a8 [ 3813.849439] check_memory_region+0x240/0x270 [ 3813.850094] memcpy+0x30/0x80 [ 3813.850553] sg_copy_buffer+0x157/0x1e0 [ 3813.853032] sg_copy_from_buffer+0x13/0x20 [ 3813.853660] fill_from_dev_buffer+0x135/0x370 [ 3813.854329] resp_readcap16+0x1ac/0x280 [ 3813.856917] schedule_resp+0x41f/0x1630 [ 3813.858203] scsi_debug_queuecommand+0xb32/0x17e0 [ 3813.862699] scsi_dispatch_cmd+0x330/0x950 [ 3813.863329] scsi_request_fn+0xd8e/0x1710 [ 3813.863946] __blk_run_queue+0x10b/0x230 [ 3813.864544] blk_execute_rq_nowait+0x1d8/0x400 [ 3813.865220] sg_common_write.isra.0+0xe61/0x2420 [ 3813.871637] sg_write+0x6c8/0xef0 [ 3813.878853] __vfs_write+0xe4/0x800 [ 3813.883487] vfs_write+0x17b/0x530 [ 3813.884008] ksys_write+0x103/0x270 [ 3813.886268] __x64_sys_write+0x77/0xc0 [ 3813.886841] do_syscall_64+0x106/0x360 [ 3813.887415] entry_SYSCALL_64_after_hwframe+0x44/0xa9 We can reproduce this issue with following syzkaller log: r0 = openat(0xffffffffffffff9c, &(0x7f0000000040)='./file0\x00', 0x26e1, 0x0) r1 = syz_open_procfs(0xffffffffffffffff, &(0x7f0000000000)='fd/3\x00') open_by_handle_at(r1, &(0x7f00000003c0)=ANY=[@ANYRESHEX], 0x602000) r2 = syz_open_dev$sg(&(0x7f0000000000), 0x0, 0x40782) write$binfmt_aout(r2, &(0x7f0000000340)=ANY=[@ANYBLOB="00000000deff000000000000000000000000000000000000000000000000000047f007af9e107a41ec395f1bded7be24277a1501ff6196a83366f4e6362bc0ff2b247f68a972989b094b2da4fb3607fcf611a22dd04310d28c75039d"], 0x126) As in resp_readcap16 we get "int alloc_len" value -1104926854, and then pass huge arr_len to fill_from_dev_buffer, but arr is only has 32 bytes space. So lead to OOB in sg_copy_buffer. To solve this issue just define alloc_len with U32 type. Signed-off-by: Ye Bin Acked-by: Douglas Gilbert --- drivers/scsi/scsi_debug.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c index 66f507469a31..be0440545744 100644 --- a/drivers/scsi/scsi_debug.c +++ b/drivers/scsi/scsi_debug.c @@ -1856,7 +1856,7 @@ static int resp_readcap16(struct scsi_cmnd *scp, { unsigned char *cmd = scp->cmnd; unsigned char arr[SDEBUG_READCAP16_ARR_SZ]; - int alloc_len; + u32 alloc_len; alloc_len = get_unaligned_be32(cmd + 10); /* following just in case virtual_gb changed */ @@ -1885,7 +1885,7 @@ static int resp_readcap16(struct scsi_cmnd *scp, } return fill_from_dev_buffer(scp, arr, - min_t(int, alloc_len, SDEBUG_READCAP16_ARR_SZ)); + min_t(u32, alloc_len, SDEBUG_READCAP16_ARR_SZ)); } #define SDEBUG_MAX_TGTPGS_ARR_SZ 1412