msm: IPA: add the check on intf query

The ipa_ioc_query_intf_rx_props structure comes
from the ioctl handler, and it is verified that
the size of rx buffer does not exceed the
IPA_NUM_PROPS_MAX elements. It is also verified
that the "entry->rx" buffer does not exceed
IPA_NUM_PROPS_MAX when "entry" is allocated.
However, the sizes of the buffer "rx->rx" and
the buffer "entry->rx" are not guaranteed to
be the same and will lead memory corruption
issue. The fix is to add the check before
memcpy.

Bug: 34026243
Bug: 35048450
Bug: 35047780
Bug: 35047217

Change-Id: Idf5c2d32f47c1a1cffeaa5607193855188893ddb
Signed-off-by: Skylar Chang <chiaweic@codeaurora.org>

drivers/platform/msm/ipa/ipa_intf.c

-/* Copyright (c) 2013-2015, The Linux Foundation. All rights reserved.
+/* Copyright (c) 2013-2017, 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
@@ -275,6 +275,14 @@ int ipa_query_intf_tx_props(struct ipa_ioc_query_intf_tx_props *tx)
 	mutex_lock(&ipa_ctx->lock);
 	list_for_each_entry(entry, &ipa_ctx->intf_list, link) {
 		if (!strncmp(entry->name, tx->name, IPA_RESOURCE_NAME_MAX)) {
+			/* add the entry check */
+			if (entry->num_tx_props != tx->num_tx_props) {
+				IPAERR("invalid entry number(%u %u)\n",
+					entry->num_tx_props,
+						tx->num_tx_props);
+				mutex_unlock(&ipa_ctx->lock);
+				return result;
+			}
 			memcpy(tx->tx, entry->tx, entry->num_tx_props *
 			       sizeof(struct ipa_ioc_tx_intf_prop));
 			result = 0;
@@ -308,6 +316,14 @@ int ipa_query_intf_rx_props(struct ipa_ioc_query_intf_rx_props *rx)
 	mutex_lock(&ipa_ctx->lock);
 	list_for_each_entry(entry, &ipa_ctx->intf_list, link) {
 		if (!strncmp(entry->name, rx->name, IPA_RESOURCE_NAME_MAX)) {
+			/* add the entry check */
+			if (entry->num_rx_props != rx->num_rx_props) {
+				IPAERR("invalid entry number(%u %u)\n",
+					entry->num_rx_props,
+						rx->num_rx_props);
+				mutex_unlock(&ipa_ctx->lock);
+				return result;
+			}
 			memcpy(rx->rx, entry->rx, entry->num_rx_props *
 					sizeof(struct ipa_ioc_rx_intf_prop));
 			result = 0;
@@ -341,6 +357,14 @@ int ipa_query_intf_ext_props(struct ipa_ioc_query_intf_ext_props *ext)
 	mutex_lock(&ipa_ctx->lock);
 	list_for_each_entry(entry, &ipa_ctx->intf_list, link) {
 		if (!strcmp(entry->name, ext->name)) {
+			/* add the entry check */
+			if (entry->num_ext_props != ext->num_ext_props) {
+				IPAERR("invalid entry number(%u %u)\n",
+					entry->num_ext_props,
+						ext->num_ext_props);
+				mutex_unlock(&ipa_ctx->lock);
+				return result;
+			}
 			memcpy(ext->ext, entry->ext, entry->num_ext_props *
 					sizeof(struct ipa_ioc_ext_intf_prop));
 			result = 0;