From: Joe Perches <joe@perches.com>
To: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
"Rafael J. Wysocki" <rafael@kernel.org>
Cc: Kees Cook <keescook@chromium.org>,
"Gustavo A . R . Silva" <gustavoars@kernel.org>,
Denis Efremov <efremov@linux.com>,
Julia Lawall <julia.lawall@inria.fr>,
Alex Dewar <alex.dewar90@gmail.com>,
Jonathan Corbet <corbet@lwn.net>,
linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH V2] sysfs: Add sysfs_emit and sysfs_emit_at to format sysfs output
Date: Sat, 29 Aug 2020 17:43:58 -0700 [thread overview]
Message-ID: <c22b7006813b1776467a72e716a5970e9277b4b7.camel@perches.com> (raw)
In-Reply-To: <a9054fb521e65f2809671fa9c18e2453061e9d91.1598744610.git.joe@perches.com>
On Sat, 2020-08-29 at 16:48 -0700, Joe Perches wrote:
> Output defects can exist in sysfs content using sprintf and snprintf.
>
> sprintf does not know the PAGE_SIZE maximum of the temporary buffer
> used for outputting sysfs content and it's possible to overrun the
> PAGE_SIZE buffer length.
>
> Add a generic sysfs_emit function that knows that the size of the
> temporary buffer and ensures that no overrun is done.
>
> Add a generic sysfs_emit_at function that can be used in multiple
> call situations that also ensures that no overrun is done.
This preliminary coccinelle script converts ~5000 instances treewide.
There are still many remaining instances that could be converted.
$ git grep -w sysfs_emit -- '*.[ch]'|wc -l
4702
$ git grep -w sysfs_emit_at -- '*.[ch]'|wc -l
229
$ cat sysfs_emit.cocci
@@
identifier d_show =~ "^.*show.*$";
identifier arg1, arg2, arg3;
@@
ssize_t d_show(struct device *
- arg1
+ dev
, struct device_attribute *
- arg2
+ attr
, char *
- arg3
+ buf
)
{
...
(
- arg1
+ dev
|
- arg2
+ attr
|
- arg3
+ buf
)
...
}
@@
identifier d_show =~ "^.*show.*$";
identifier dev, attr, buf;
@@
ssize_t d_show(struct device *dev, struct device_attribute *attr, char *buf)
{
<...
return
- sprintf(buf,
+ sysfs_emit(buf,
...);
...>
}
@@
identifier d_show =~ "^.*show.*$";
identifier dev, attr, buf;
@@
ssize_t d_show(struct device *dev, struct device_attribute *attr, char *buf)
{
<...
return
- snprintf(buf, PAGE_SIZE,
+ sysfs_emit(buf,
...);
...>
}
@@
identifier d_show =~ "^.*show.*$";
identifier dev, attr, buf;
@@
ssize_t d_show(struct device *dev, struct device_attribute *attr, char *buf)
{
<...
return
- scnprintf(buf, PAGE_SIZE,
+ sysfs_emit(buf,
...);
...>
}
@@
identifier d_show =~ "^.*show.*$";
identifier dev, attr, buf;
expression chr;
@@
ssize_t d_show(struct device *dev, struct device_attribute *attr, char *buf)
{
<...
return
- strcpy(buf, chr);
+ sysfs_emit(buf, chr);
...>
}
@@
identifier d_show =~ "^.*show.*$";
identifier dev, attr, buf;
identifier len;
@@
ssize_t d_show(struct device *dev, struct device_attribute *attr, char *buf)
{
<...
len =
- sprintf(buf,
+ sysfs_emit(buf,
...);
...>
return len;
}
@@
identifier d_show =~ "^.*show.*$";
identifier dev, attr, buf;
identifier len;
@@
ssize_t d_show(struct device *dev, struct device_attribute *attr, char *buf)
{
<...
len =
- snprintf(buf, PAGE_SIZE,
+ sysfs_emit(buf,
...);
...>
return len;
}
@@
identifier d_show =~ "^.*show.*$";
identifier dev, attr, buf;
identifier len;
@@
ssize_t d_show(struct device *dev, struct device_attribute *attr, char *buf)
{
<...
len =
- scnprintf(buf, PAGE_SIZE,
+ sysfs_emit(buf,
...);
...>
return len;
}
@@
identifier d_show =~ "^.*show.*$";
identifier dev, attr, buf;
identifier len;
@@
ssize_t d_show(struct device *dev, struct device_attribute *attr, char *buf)
{
<...
- len += scnprintf(buf + len, PAGE_SIZE - len,
+ len += sysfs_emit_at(buf, len,
...);
...>
return len;
}
@@
identifier d_show =~ "^.*show.*$";
identifier dev, attr, buf;
expression chr;
@@
ssize_t d_show(struct device *dev, struct device_attribute *attr, char *buf)
{
- strcpy(buf, chr);
- return strlen(buf);
+ return sysfs_emit(buf, chr);
}
@@
identifier k_show =~ "^.*show.*$";
identifier arg1, arg2, arg3;
@@
ssize_t k_show(struct kobject *
- arg1
+ kobj
, struct kobj_attribute *
- arg2
+ attr
, char *
- arg3
+ buf
)
{
...
(
- arg1
+ kobj
|
- arg2
+ attr
|
- arg3
+ buf
)
...
}
@@
identifier k_show =~ "^.*show.*$";
identifier kobj, attr, buf;
@@
ssize_t k_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
{
<...
return
- sprintf(buf,
+ sysfs_emit(buf,
...);
...>
}
@@
identifier k_show =~ "^.*show.*$";
identifier kobj, attr, buf;
@@
ssize_t k_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
{
<...
return
- snprintf(buf, PAGE_SIZE,
+ sysfs_emit(buf,
...);
...>
}
@@
identifier k_show =~ "^.*show.*$";
identifier kobj, attr, buf;
@@
ssize_t k_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
{
<...
return
- scnprintf(buf, PAGE_SIZE,
+ sysfs_emit(buf,
...);
...>
}
@@
identifier k_show =~ "^.*show.*$";
identifier kobj, attr, buf;
expression chr;
@@
ssize_t k_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
{
<...
return
- strcpy(buf, chr);
+ sysfs_emit(buf, chr);
...>
}
@@
identifier k_show =~ "^.*show.*$";
identifier kobj, attr, buf;
identifier len;
@@
ssize_t k_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
{
<...
len =
- sprintf(buf,
+ sysfs_emit(buf,
...);
...>
return len;
}
@@
identifier k_show =~ "^.*show.*$";
identifier kobj, attr, buf;
identifier len;
@@
ssize_t k_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
{
<...
len =
- snprintf(buf, PAGE_SIZE,
+ sysfs_emit(buf,
...);
...>
return len;
}
@@
identifier k_show =~ "^.*show.*$";
identifier kobj, attr, buf;
identifier len;
@@
ssize_t k_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
{
<...
len =
- scnprintf(buf, PAGE_SIZE,
+ sysfs_emit(buf,
...);
...>
return len;
}
@@
identifier k_show =~ "^.*show.*$";
identifier kobj, attr, buf;
identifier len;
@@
ssize_t k_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
{
<...
- len += scnprintf(buf + len, PAGE_SIZE - len,
+ len += sysfs_emit_at(buf, len,
...);
...>
return len;
}
@@
identifier k_show =~ "^.*show.*$";
identifier kobj, attr, buf;
expression chr;
@@
ssize_t k_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
{
- strcpy(buf, chr);
- return strlen(buf);
+ return sysfs_emit(buf, chr);
}
next prev parent reply other threads:[~2020-08-30 0:44 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-08-29 23:48 [PATCH V2] sysfs: Add sysfs_emit and sysfs_emit_at to format sysfs output Joe Perches
2020-08-30 0:43 ` Joe Perches [this message]
2020-08-30 8:59 ` Julia Lawall
2020-08-30 15:25 ` Denis Efremov
2020-08-30 16:05 ` Joe Perches
2020-09-07 13:36 ` Greg Kroah-Hartman
2020-09-06 17:24 ` Joe Perches
2020-09-07 5:48 ` Greg Kroah-Hartman
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