Commit 8e2e2312 authored Jan 12, 2017 by Conner Huff Committed by Gerrit - the friendly Code Review server Jan 24, 2017

net: rmnet_data: Fix incorrect netlink handling



rmnet_data netlink handler currently does not check for the
incoming process pid and instead just loops back the pid.
A malicious root user could potentially send a message with
source pid 0 and this could cause rmnet_data to loop the message
back till an out of memory situation occurs.

rmnet_data also does not check for the message length of the
incoming netlink messages and instead casts the netlink message
without checking for the boundary.

Fix these two scenarios by adding the pid and message length checks
respectively.

Bug: 31252965
CRs-Fixed: 1098801
Change-Id: I172c1a7112e67e82959b397af7ddfd963d819bdc
Signed-off-by: Conner Huff <chuff@codeaurora.org>

parent a1c3a94c

net/rmnet_data/rmnet_data_config.c

+6 −1

Original line number	Diff line number	Diff line
		/*
		* Copyright (c) 2013-2015, The Linux Foundation. All rights reserved.
		* Copyright (c) 2013-2015, 2017 The Linux Foundation. All rights reserved.
		*
		* This program is free software; you can redistribute it and/or modify
		* it under the terms of the GNU General Public License version 2 and
		@@ -531,6 +531,11 @@ void rmnet_config_netlink_msg_handler(struct sk_buff *skb)
		nlmsg_header = (struct nlmsghdr *) skb->data;
		rmnet_header = (struct rmnet_nl_msg_s *) nlmsg_data(nlmsg_header);

		if (!nlmsg_header->nlmsg_pid \|\|
		(nlmsg_header->nlmsg_len < sizeof(struct nlmsghdr) +
		sizeof(struct rmnet_nl_msg_s)))
		return;

		LOGL("Netlink message pid=%d, seq=%d, length=%d, rmnet_type=%d",
		nlmsg_header->nlmsg_pid,
		nlmsg_header->nlmsg_seq,