lkml.org 
[lkml]   [2011]   [Jul]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] libfs: fix simple_attr_write on 32bit machine
On Sat,  9 Jul 2011 14:00:26 +0900
Akinobu Mita <akinobu.mita@gmail.com> wrote:

> Assume that /sys/kernel/debug/dummy64 is debugfs file created by
> debugfs_create_x64().
>
> # cd /sys/kernel/debug
> # echo 0x1234567812345678 > dummy64
> # cat dummy64
> 0x0000000012345678
>
> # echo 0x80000000 > dummy64
> # cat dummy64
> 0xffffffff80000000
>
> The value more than INT_MAX cannot be written to the debugfs file
> created by debugfs_create_u64 or debugfs_create_x64 on 32bit machine.
> Because simple_attr_write() uses simple_strtol() for the conversion.
>
> To fix this, use simple_strtoll() instead.
>
> Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
> Cc: Greg Kroah-Hartman <gregkh@suse.de>
> ---
> fs/libfs.c | 2 +-
> 1 files changed, 1 insertions(+), 1 deletions(-)
>
> diff --git a/fs/libfs.c b/fs/libfs.c
> index c88eab5..275ca474 100644
> --- a/fs/libfs.c
> +++ b/fs/libfs.c
> @@ -822,7 +822,7 @@ ssize_t simple_attr_write(struct file *file, const char __user *buf,
> goto out;
>
> attr->set_buf[size] = '\0';
> - val = simple_strtol(attr->set_buf, NULL, 0);
> + val = simple_strtoll(attr->set_buf, NULL, 0);
> ret = attr->set(attr->data, val);
> if (ret == 0)
> ret = len; /* on success, claim we got the whole input */

It should strictly be simple_strtoull(), but I guess that doesn't
change anything.

And it should always have been strict_*(), now known as kstrto*(). But
that interface fix is non-back-compatible so it's too late to fix it.



\
 
 \ /
  Last update: 2011-07-13 00:27    [W:0.046 / U:0.548 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site