linux/net/wireless/debugfs.c
Eliad Peller f364ef99a8 mac80211: fix some snprintf misuses
In some debugfs related functions snprintf was used
while scnprintf should have been used instead.

(blindly adding the return value of snprintf and supplying
it to the next snprintf might result in buffer overflow when
the input is too big)

Signed-off-by: Eliad Peller <eliad@wizery.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-10-01 12:16:51 +02:00

117 lines
3 KiB
C

/*
* cfg80211 debugfs
*
* Copyright 2009 Luis R. Rodriguez <lrodriguez@atheros.com>
* Copyright 2007 Johannes Berg <johannes@sipsolutions.net>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/slab.h>
#include "core.h"
#include "debugfs.h"
#define DEBUGFS_READONLY_FILE(name, buflen, fmt, value...) \
static ssize_t name## _read(struct file *file, char __user *userbuf, \
size_t count, loff_t *ppos) \
{ \
struct wiphy *wiphy= file->private_data; \
char buf[buflen]; \
int res; \
\
res = scnprintf(buf, buflen, fmt "\n", ##value); \
return simple_read_from_buffer(userbuf, count, ppos, buf, res); \
} \
\
static const struct file_operations name## _ops = { \
.read = name## _read, \
.open = simple_open, \
.llseek = generic_file_llseek, \
};
DEBUGFS_READONLY_FILE(rts_threshold, 20, "%d",
wiphy->rts_threshold)
DEBUGFS_READONLY_FILE(fragmentation_threshold, 20, "%d",
wiphy->frag_threshold);
DEBUGFS_READONLY_FILE(short_retry_limit, 20, "%d",
wiphy->retry_short)
DEBUGFS_READONLY_FILE(long_retry_limit, 20, "%d",
wiphy->retry_long);
static int ht_print_chan(struct ieee80211_channel *chan,
char *buf, int buf_size, int offset)
{
if (WARN_ON(offset > buf_size))
return 0;
if (chan->flags & IEEE80211_CHAN_DISABLED)
return scnprintf(buf + offset,
buf_size - offset,
"%d Disabled\n",
chan->center_freq);
return scnprintf(buf + offset,
buf_size - offset,
"%d HT40 %c%c\n",
chan->center_freq,
(chan->flags & IEEE80211_CHAN_NO_HT40MINUS) ?
' ' : '-',
(chan->flags & IEEE80211_CHAN_NO_HT40PLUS) ?
' ' : '+');
}
static ssize_t ht40allow_map_read(struct file *file,
char __user *user_buf,
size_t count, loff_t *ppos)
{
struct wiphy *wiphy = file->private_data;
char *buf;
unsigned int offset = 0, buf_size = PAGE_SIZE, i, r;
enum ieee80211_band band;
struct ieee80211_supported_band *sband;
buf = kzalloc(buf_size, GFP_KERNEL);
if (!buf)
return -ENOMEM;
rtnl_lock();
for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
sband = wiphy->bands[band];
if (!sband)
continue;
for (i = 0; i < sband->n_channels; i++)
offset += ht_print_chan(&sband->channels[i],
buf, buf_size, offset);
}
rtnl_unlock();
r = simple_read_from_buffer(user_buf, count, ppos, buf, offset);
kfree(buf);
return r;
}
static const struct file_operations ht40allow_map_ops = {
.read = ht40allow_map_read,
.open = simple_open,
.llseek = default_llseek,
};
#define DEBUGFS_ADD(name) \
debugfs_create_file(#name, S_IRUGO, phyd, &rdev->wiphy, &name## _ops);
void cfg80211_debugfs_rdev_add(struct cfg80211_registered_device *rdev)
{
struct dentry *phyd = rdev->wiphy.debugfsdir;
DEBUGFS_ADD(rts_threshold);
DEBUGFS_ADD(fragmentation_threshold);
DEBUGFS_ADD(short_retry_limit);
DEBUGFS_ADD(long_retry_limit);
DEBUGFS_ADD(ht40allow_map);
}