lkml.org 
[lkml]   [2015]   [Aug]   [21]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH] mtd: blktrans: fix integer overflow
Date
In drivers/mtd/mtd_blkdevs.c:
406 set_capacity(gd, (new->size * tr->blksize) >> 9);
The type of new->size is unsigned long and the type of tr->blksize is int,
the result of 'new->size * tr->blksize' may exceed ULONG_MAX on 32bit
machines.

I use nand chip MT29F32G08CBADBWP which is 4GB and the parameters passed
to kernel is 'mtdparts=gpmi-nand:-(user)', the whole nand chip will be
treated as a 4GB mtd partition. new->size is 0x800000 and tr->blksize is
0x200, 'new->size * tr->blksize' however is 0. This is what we do not want
to see.

Change the type of entry size of mtd_blktrans_dev to unsigned long long
to fix the overflow issue.

Signed-off-by: Peng Fan <van.freenix@gmail.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Brian Norris <computersforpeace@gmail.com>
---
include/linux/mtd/blktrans.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/linux/mtd/blktrans.h b/include/linux/mtd/blktrans.h
index e93837f..3853d74 100644
--- a/include/linux/mtd/blktrans.h
+++ b/include/linux/mtd/blktrans.h
@@ -38,7 +38,7 @@ struct mtd_blktrans_dev {
struct mutex lock;
int devnum;
bool bg_stop;
- unsigned long size;
+ unsigned long long size;
int readonly;
int open;
struct kref ref;
--
1.8.4


\
 
 \ /
  Last update: 2015-08-21 17:21    [W:0.067 / U:0.164 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site