[ 015/104] iwlwifi: fix freeing uninitialized pointer

Greg Kroah-Hartman
2013-05-06T23:13:21Z

From: Stanislaw Gruszka <sgruszka@redhat.com>

commit 3309ccf7fcebceef540ebe90c65d2f94d745a45b upstream.

If on iwl_dump_nic_event_log() error occurs before that function
initialize buf, we process uninitiated pointer in
iwl_dbgfs_log_event_read() and can hit "BUG at mm/slub.c:3409"

Resolves:
https://bugzilla.redhat.com/show_bug.cgi?id=951241

Reported-by: ian.odette@eprize.com
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/net/wireless/iwlwifi/dvm/debugfs.c | 16 ++++++++--------
1 file changed, 8 insertions(+), 8 deletions(-)

--- a/drivers/net/wireless/iwlwifi/dvm/debugfs.c
+++ b/drivers/net/wireless/iwlwifi/dvm/debugfs.c
@@ -2237,15 +2237,15 @@ static ssize_t iwl_dbgfs_log_event_read(
size_t count, loff_t *ppos)
{
struct iwl_priv *priv = file->private_data;
- char *buf;
- int pos = 0;
- ssize_t ret = -ENOMEM;
+ char *buf = NULL;
+ ssize_t ret;

- ret = pos = iwl_dump_nic_event_log(priv, true, &buf, true);
- if (buf) {
- ret = simple_read_from_buffer(user_buf, count, ppos, buf, pos);
- kfree(buf);
- }
+ ret = iwl_dump_nic_event_log(priv, true, &buf, true);
+ if (ret < 0)
+ goto err;
+ ret = simple_read_from_buffer(user_buf, count, ppos, buf, ret);
+err:
+ kfree(buf);
return ret;
}