linux-kernel - [04/48] mtd: tests: stresstest: bail out if device has not enough eraseblocks

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20120116184516.129143102@clark.kroah.org>
Date:	Mon, 16 Jan 2012 10:44:31 -0800
From:	Greg KH <gregkh@...e.de>
To:	linux-kernel@...r.kernel.org, stable@...r.kernel.org
Cc:	torvalds@...ux-foundation.org, akpm@...ux-foundation.org,
	alan@...rguk.ukuu.org.uk, Wolfram Sang <w.sang@...gutronix.de>,
	Artem Bityutskiy <artem.bityutskiy@...ux.intel.com>,
	David Woodhouse <David.Woodhouse@...el.com>
Subject: [04/48] mtd: tests: stresstest: bail out if device has not enough eraseblocks

3.1-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Wolfram Sang <w.sang@...gutronix.de>

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 <w.sang@...gutronix.de>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@...ux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@...el.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@...e.de>

---
 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
@@ -277,6 +277,12 @@ 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;
 
@@ -315,6 +321,7 @@ out:
 	kfree(bbt);
 	vfree(writebuf);
 	vfree(readbuf);
+out_put_mtd:
 	put_mtd_device(mtd);
 	if (err)
 		printk(PRINT_PREF "error %d occurred\n", err);


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/