diff options
| author | David Fries <David@Fries.net> | 2014-11-10 20:19:36 -0600 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2014-11-26 19:09:01 -0800 |
| commit | a30cfa475d1a26c18f1998ba1e034a4e2ab4c7a8 (patch) | |
| tree | 0d352909e457fca03a206f1a7fe10174ed7e5ba9 /drivers/connector/connector.c | |
| parent | 55c4e6405d434e2db1e3fb3618b84741bb17d862 (diff) | |
| download | lwn-a30cfa475d1a26c18f1998ba1e034a4e2ab4c7a8.tar.gz lwn-a30cfa475d1a26c18f1998ba1e034a4e2ab4c7a8.zip | |
cn: verify msg->len before making callback
The struct cn_msg len field comes from userspace and needs to be
validated. More logical to do so here where the cn_msg pointer is
pulled out of the sk_buff than the callback which is passed cn_msg *
and might assume no validation is needed.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: David Fries <David@Fries.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/connector/connector.c')
| -rw-r--r-- | drivers/connector/connector.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/drivers/connector/connector.c b/drivers/connector/connector.c index f612d68629dc..30f522848c73 100644 --- a/drivers/connector/connector.c +++ b/drivers/connector/connector.c @@ -141,12 +141,18 @@ EXPORT_SYMBOL_GPL(cn_netlink_send); */ static int cn_call_callback(struct sk_buff *skb) { + struct nlmsghdr *nlh; struct cn_callback_entry *i, *cbq = NULL; struct cn_dev *dev = &cdev; struct cn_msg *msg = nlmsg_data(nlmsg_hdr(skb)); struct netlink_skb_parms *nsp = &NETLINK_CB(skb); int err = -ENODEV; + /* verify msg->len is within skb */ + nlh = nlmsg_hdr(skb); + if (nlh->nlmsg_len < NLMSG_HDRLEN + sizeof(struct cn_msg) + msg->len) + return -EINVAL; + spin_lock_bh(&dev->cbdev->queue_lock); list_for_each_entry(i, &dev->cbdev->queue_list, callback_entry) { if (cn_cb_equal(&i->id.id, &msg->id)) { |