mac80211: add NULL terminator to debugfs_netdev write buf
Some debugfs write functions call kstrto* functions, which
assume the string is null-terminated. Make it valid by changing
ieee80211_if_write() to use static buffer instead of allocating
one, and set the last char to NULL.
(The write functions try to parse some integer/mac address,
so 64 bytes buffer should be enough)
Signed-off-by: Eliad Peller <eliad@wizery.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/mac80211/debugfs_netdev.c b/net/mac80211/debugfs_netdev.c
index f6de8a6..ef5cf26 100644
--- a/net/mac80211/debugfs_netdev.c
+++ b/net/mac80211/debugfs_netdev.c
@@ -49,16 +49,15 @@
size_t count, loff_t *ppos,
ssize_t (*write)(struct ieee80211_sub_if_data *, const char *, int))
{
- u8 *buf;
+ char buf[64];
ssize_t ret;
- buf = kmalloc(count, GFP_KERNEL);
- if (!buf)
- return -ENOMEM;
+ if (count >= sizeof(buf))
+ return -E2BIG;
- ret = -EFAULT;
if (copy_from_user(buf, userbuf, count))
- goto freebuf;
+ return -EFAULT;
+ buf[count] = '\0';
ret = -ENODEV;
rtnl_lock();
@@ -66,8 +65,6 @@
ret = (*write)(sdata, buf, count);
rtnl_unlock();
-freebuf:
- kfree(buf);
return ret;
}