From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Message-Id: <20120124023924.297344106@clark.kroah.org> Date: Mon, 23 Jan 2012 18:33:44 -0800 From: Greg KH To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Wolfram Sang , Artem Bityutskiy , David Woodhouse Subject: [004/129] mtd: tests: stresstest: bail out if device has not enough eraseblocks In-Reply-To: <20120124024041.GA18422@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.2-stable review patch. If anyone has any objections, please let me know. ------------------ Content-Length: 1732 Lines: 53 From: Wolfram Sang commit 2f4478ccff7df845dc9c0f8996a96373122c4417 upstream. stresstest needs at least two eraseblocks. Bail out gracefully if that condition is not met. Fixes the following 'division by zero' OOPS: [ 619.100000] mtd_stresstest: MTD device size 131072, eraseblock size 131072, page size 2048, count of eraseblocks 1, pages per eraseblock 64, OOB size 64 [ 619.120000] mtd_stresstest: scanning for bad eraseblocks [ 619.120000] mtd_stresstest: scanned 1 eraseblocks, 0 are bad [ 619.130000] mtd_stresstest: doing operations [ 619.130000] mtd_stresstest: 0 operations done [ 619.140000] Division by zero in kernel. ... caused by /* Read or write up 2 eraseblocks at a time - hence 'ebcnt - 1' */ eb %= (ebcnt - 1); Signed-off-by: Wolfram Sang Signed-off-by: Artem Bityutskiy Signed-off-by: David Woodhouse Signed-off-by: Greg Kroah-Hartman --- drivers/mtd/tests/mtd_stresstest.c | 7 +++++++ 1 file changed, 7 insertions(+) --- a/drivers/mtd/tests/mtd_stresstest.c +++ b/drivers/mtd/tests/mtd_stresstest.c @@ -284,6 +284,12 @@ static int __init mtd_stresstest_init(vo (unsigned long long)mtd->size, mtd->erasesize, pgsize, ebcnt, pgcnt, mtd->oobsize); + if (ebcnt < 2) { + printk(PRINT_PREF "error: need at least 2 eraseblocks\n"); + err = -ENOSPC; + goto out_put_mtd; + } + /* Read or write up 2 eraseblocks at a time */ bufsize = mtd->erasesize * 2; @@ -322,6 +328,7 @@ out: kfree(bbt); vfree(writebuf); vfree(readbuf); +out_put_mtd: put_mtd_device(mtd); if (err) printk(PRINT_PREF "error %d occurred\n", err);