mac80211: fix failure to check kmalloc return value in key_key_read
I noticed two small issues in mac80211/debugfs_key.c::key_key_read while
reading through the code. Patch below.
The key_key_read() function returns ssize_t and the value that's actually
returned is the return value of simple_read_from_buffer() which also
returns ssize_t, so let's hold the return value in a ssize_t local
variable rather than a int one.
Also, memory is allocated dynamically with kmalloc() which can fail, but
the return value of kmalloc() is not checked, so we may end up operating
on a null pointer further on. So check for a NULL return and bail out with
-ENOMEM in that case.
Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/mac80211/debugfs_key.c b/net/mac80211/debugfs_key.c
index 4aa47d0..1243d1d 100644
--- a/net/mac80211/debugfs_key.c
+++ b/net/mac80211/debugfs_key.c
@@ -203,9 +203,13 @@
size_t count, loff_t *ppos)
{
struct ieee80211_key *key = file->private_data;
- int i, res, bufsize = 2 * key->conf.keylen + 2;
+ int i, bufsize = 2 * key->conf.keylen + 2;
char *buf = kmalloc(bufsize, GFP_KERNEL);
char *p = buf;
+ ssize_t res;
+
+ if (!buf)
+ return -ENOMEM;
for (i = 0; i < key->conf.keylen; i++)
p += scnprintf(p, bufsize + buf - p, "%02x", key->conf.key[i]);