batman-adv: Only write requested number of byte to user buffer

Don't write more than the requested number of bytes of an batman-adv icmp
packet to the userspace buffer. Otherwise unrelated userspace memory might get
overridden by the kernel.

Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
This commit is contained in:
Sven Eckelmann 2011-12-10 15:28:36 +01:00 committed by Marek Lindner
parent d18eb45332
commit b5a1eeef04

View File

@ -136,10 +136,9 @@ static ssize_t bat_socket_read(struct file *file, char __user *buf,
spin_unlock_bh(&socket_client->lock);
error = copy_to_user(buf, &socket_packet->icmp_packet,
socket_packet->icmp_len);
packet_len = min(count, socket_packet->icmp_len);
error = copy_to_user(buf, &socket_packet->icmp_packet, packet_len);
packet_len = socket_packet->icmp_len;
kfree(socket_packet);
if (error)