mtd: mtdoops: limit the maximum mtd partition size

Make the maximum mtdoops partition size to be 8MiB. Indeed, it does
not make sense to use anything larger than that anyway. This limit
makes it possible to catch stupid mistakes where the user gives e.g.,
a rootfs partition to mtdoops (which will happily erase it).

Signed-off-by: Simon Kagstrom <simon.kagstrom@netinsight.net>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
This commit is contained in:
Simon Kagstrom 2009-11-03 08:08:41 +02:00 committed by David Woodhouse
parent be95745f01
commit 1114e3d00f
1 changed files with 11 additions and 6 deletions

View File

@ -33,6 +33,9 @@
#include <linux/interrupt.h>
#include <linux/mtd/mtd.h>
/* Maximum MTD partition size */
#define MTDOOPS_MAX_MTD_SIZE (8 * 1024 * 1024)
#define MTDOOPS_KERNMSG_MAGIC 0x5d005d00
#define OOPS_PAGE_SIZE 4096
@ -310,6 +313,12 @@ static void mtdoops_notify_add(struct mtd_info *mtd)
return;
}
if (mtd->size > MTDOOPS_MAX_MTD_SIZE) {
printk(KERN_ERR "mtdoops: mtd%d is too large (limit is %d MiB)\n",
mtd->index, MTDOOPS_MAX_MTD_SIZE / 1024 / 1024);
return;
}
/* oops_page_used is a bit field */
cxt->oops_page_used = vmalloc(DIV_ROUND_UP(mtdoops_pages,
BITS_PER_LONG));
@ -317,14 +326,10 @@ static void mtdoops_notify_add(struct mtd_info *mtd)
printk(KERN_ERR "Could not allocate page array\n");
return;
}
cxt->mtd = mtd;
if (mtd->size > INT_MAX)
cxt->oops_pages = INT_MAX / OOPS_PAGE_SIZE;
else
cxt->oops_pages = (int)mtd->size / OOPS_PAGE_SIZE;
cxt->oops_pages = (int)mtd->size / OOPS_PAGE_SIZE;
find_next_position(cxt);
printk(KERN_INFO "mtdoops: Attached to MTD device %d\n", mtd->index);
}