From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marek Lindner Subject: [PATCH 11/11] batman-adv: Only write requested number of byte to user buffer Date: Mon, 12 Dec 2011 19:31:55 +0800 Message-ID: <1323689516-24427-12-git-send-email-lindner_marek@yahoo.de> References: <1323689516-24427-1-git-send-email-lindner_marek@yahoo.de> Cc: netdev@vger.kernel.org, b.a.t.m.a.n@lists.open-mesh.org, Sven Eckelmann , Marek Lindner To: davem@davemloft.net Return-path: Received: from nm15.bullet.mail.ukl.yahoo.com ([217.146.183.189]:34901 "HELO nm15.bullet.mail.ukl.yahoo.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1752546Ab1LLLdQ (ORCPT ); Mon, 12 Dec 2011 06:33:16 -0500 In-Reply-To: <1323689516-24427-1-git-send-email-lindner_marek@yahoo.de> Sender: netdev-owner@vger.kernel.org List-ID: From: Sven Eckelmann 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 Signed-off-by: Marek Lindner --- net/batman-adv/icmp_socket.c | 5 ++--- 1 files changed, 2 insertions(+), 3 deletions(-) diff --git a/net/batman-adv/icmp_socket.c b/net/batman-adv/icmp_socket.c index 3b04fff..d9c1e7b 100644 --- a/net/batman-adv/icmp_socket.c +++ b/net/batman-adv/icmp_socket.c @@ -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) -- 1.7.5.4