Fix OOB in avrc_pars_browse_rsp
- Check packet length before assign bytes to the pointer.
Bug: 111451066
Test: PoC test
Change-Id: I8ce4f4678a043fc16b0beeea2345253e7542b506
(cherry picked from commit 32a33dc12d4a9b21306510a98bcd039ca3be1dd3)
diff --git a/stack/avrc/avrc_pars_ct.cc b/stack/avrc/avrc_pars_ct.cc
index de7c2ca..99bb465 100644
--- a/stack/avrc/avrc_pars_ct.cc
+++ b/stack/avrc/avrc_pars_ct.cc
@@ -222,29 +222,42 @@
uint8_t* p = p_msg->p_browse_data;
/* read the pdu */
+ if (p_msg->browse_len < 3) {
+ android_errorWriteLog(0x534e4554, "111451066");
+ AVRC_TRACE_WARNING("%s: message length %d too short: must be at least 3",
+ __func__, p_msg->browse_len);
+ return AVRC_STS_BAD_PARAM;
+ }
BE_STREAM_TO_UINT8(pdu, p);
uint16_t pkt_len;
+ uint16_t min_len = 0;
/* read the entire packet len */
BE_STREAM_TO_UINT16(pkt_len, p);
- AVRC_TRACE_DEBUG("%s pdu %d", __func__, pdu);
+ AVRC_TRACE_DEBUG("%s pdu:%d, pkt_len:%d", __func__, pdu, pkt_len);
- /* used to track how much we have read, if we cannot read anymore but the
- * packet says so then we have a malformed packet. Also vice versa. */
- uint16_t pkt_len_read = 0;
+ if (p_msg->browse_len < (pkt_len + 3)) {
+ android_errorWriteLog(0x534e4554, "111451066");
+ AVRC_TRACE_WARNING("%s: message length %d too short: must be at least %d",
+ __func__, p_msg->browse_len, pkt_len + 3);
+ return AVRC_STS_INTERNAL_ERR;
+ }
switch (pdu) {
case AVRC_PDU_GET_FOLDER_ITEMS: {
tAVRC_GET_ITEMS_RSP* get_item_rsp = &(p_rsp->get_items);
/* Copy back the PDU */
get_item_rsp->pdu = pdu;
+
+ min_len += 5;
+ if (pkt_len < min_len) goto browse_length_error;
+
/* read the status */
BE_STREAM_TO_UINT8(get_item_rsp->status, p);
/* read the UID counter */
BE_STREAM_TO_UINT16(get_item_rsp->uid_counter, p);
/* read the number of items */
BE_STREAM_TO_UINT16(get_item_rsp->item_count, p);
- pkt_len_read += 5;
AVRC_TRACE_DEBUG(
"%s pdu %d status %d pkt_len %d uid counter %d item count %d",
@@ -262,29 +275,32 @@
get_item_rsp->item_count * (sizeof(tAVRC_ITEM)));
tAVRC_ITEM* curr_item = get_item_rsp->p_item_list;
for (int i = 0; i < get_item_rsp->item_count; i++) {
+ min_len += 1;
+ if (pkt_len < min_len) goto browse_length_error;
BE_STREAM_TO_UINT8(curr_item->item_type, p);
- pkt_len_read += 1;
AVRC_TRACE_DEBUG("%s item type %d", __func__, curr_item->item_type);
switch (curr_item->item_type) {
case AVRC_ITEM_PLAYER: {
/* Handle player */
tAVRC_ITEM_PLAYER* player = &(curr_item->u.player);
uint8_t player_len;
+ min_len += 10 + AVRC_FEATURE_MASK_SIZE;
+ if (pkt_len < min_len) goto browse_length_error;
BE_STREAM_TO_UINT16(player_len, p);
BE_STREAM_TO_UINT16(player->player_id, p);
BE_STREAM_TO_UINT8(player->major_type, p);
BE_STREAM_TO_UINT32(player->sub_type, p);
BE_STREAM_TO_UINT8(player->play_status, p);
BE_STREAM_TO_ARRAY(p, player->features, AVRC_FEATURE_MASK_SIZE);
- pkt_len_read += (10 + AVRC_FEATURE_MASK_SIZE);
/* read str */
+ min_len += 4 + player->name.str_len;
+ if (pkt_len < min_len) goto browse_length_error;
BE_STREAM_TO_UINT16(player->name.charset_id, p);
BE_STREAM_TO_UINT16(player->name.str_len, p);
player->name.p_str = (uint8_t*)osi_malloc(
(player->name.str_len + 1) * sizeof(uint8_t));
BE_STREAM_TO_ARRAY(p, player->name.p_str, player->name.str_len);
- pkt_len_read += (4 + player->name.str_len);
AVRC_TRACE_DEBUG(
"%s type %d id %d mtype %d stype %d ps %d cs %d name len %d",
__func__, curr_item->item_type, player->player_id,
@@ -295,20 +311,22 @@
case AVRC_ITEM_FOLDER: {
tAVRC_ITEM_FOLDER* folder = &(curr_item->u.folder);
uint16_t folder_len;
+ min_len += 4 + AVRC_UID_SIZE;
+ if (pkt_len < min_len) goto browse_length_error;
BE_STREAM_TO_UINT16(folder_len, p);
BE_STREAM_TO_ARRAY(p, folder->uid, AVRC_UID_SIZE);
BE_STREAM_TO_UINT8(folder->type, p);
BE_STREAM_TO_UINT8(folder->playable, p);
- pkt_len_read += (4 + AVRC_UID_SIZE);
/* read str, encoding to be handled by upper layers */
+ min_len += 4 + folder->name.str_len;
+ if (pkt_len < min_len) goto browse_length_error;
BE_STREAM_TO_UINT16(folder->name.charset_id, p);
BE_STREAM_TO_UINT16(folder->name.str_len, p);
folder->name.p_str = (uint8_t*)osi_malloc(
(folder->name.str_len + 1) * sizeof(uint8_t));
BE_STREAM_TO_ARRAY(p, folder->name.p_str, folder->name.str_len);
- pkt_len_read += (4 + folder->name.str_len);
AVRC_TRACE_DEBUG("%s type %d playable %d cs %d name len %d",
__func__, folder->type, folder->playable,
folder->name.charset_id, folder->name.str_len);
@@ -317,12 +335,15 @@
case AVRC_ITEM_MEDIA: {
tAVRC_ITEM_MEDIA* media = &(curr_item->u.media);
uint8_t media_len;
+ min_len += 3 + AVRC_UID_SIZE;
+ if (pkt_len < min_len) goto browse_length_error;
BE_STREAM_TO_UINT16(media_len, p);
BE_STREAM_TO_ARRAY(p, media->uid, AVRC_UID_SIZE);
BE_STREAM_TO_UINT8(media->type, p);
- pkt_len_read += (3 + AVRC_UID_SIZE);
/* read str, encoding to be handled by upper layers */
+ min_len += 5 + media->name.str_len;
+ if (pkt_len < min_len) goto browse_length_error;
BE_STREAM_TO_UINT16(media->name.charset_id, p);
BE_STREAM_TO_UINT16(media->name.str_len, p);
media->name.p_str =
@@ -333,12 +354,13 @@
AVRC_TRACE_DEBUG("%s media type %d charset id %d len %d attr ct %d",
__func__, media->type, media->name.charset_id,
media->name.str_len, media->attr_count);
- pkt_len_read += (5 + media->name.str_len);
media->p_attr_list = (tAVRC_ATTR_ENTRY*)osi_malloc(
media->attr_count * sizeof(tAVRC_ATTR_ENTRY));
for (int jk = 0; jk < media->attr_count; jk++) {
tAVRC_ATTR_ENTRY* attr_entry = &(media->p_attr_list[jk]);
+ min_len += 8 + attr_entry->name.str_len;
+ if (pkt_len < min_len) goto browse_length_error;
BE_STREAM_TO_UINT32(attr_entry->attr_id, p);
/* Parse the name now */
@@ -348,7 +370,6 @@
attr_entry->name.str_len * sizeof(uint8_t));
BE_STREAM_TO_ARRAY(p, attr_entry->name.p_str,
attr_entry->name.str_len);
- pkt_len_read += (8 + attr_entry->name.str_len);
AVRC_TRACE_DEBUG("%s media attr id %d cs %d name len %d",
__func__, attr_entry->attr_id,
attr_entry->name.charset_id,
@@ -362,14 +383,8 @@
return AVRC_STS_INTERNAL_ERR;
}
- /* we check if we have overrun */
- if (pkt_len_read > pkt_len) {
- AVRC_TRACE_ERROR("%s overflow in read pkt_len %d pkt_len_read %d",
- __func__, pkt_len, pkt_len_read);
- return AVRC_STS_BAD_CMD;
- }
- AVRC_TRACE_DEBUG("%s pkt_len %d pkt_len_read %d", __func__, pkt_len,
- pkt_len_read);
+ AVRC_TRACE_DEBUG("%s pkt_len %d min_len %d", __func__, pkt_len,
+ min_len);
/* advance to populate the next item */
curr_item++;
@@ -379,13 +394,14 @@
case AVRC_PDU_CHANGE_PATH: {
tAVRC_CHG_PATH_RSP* change_path_rsp = &(p_rsp->chg_path);
+ min_len += 5;
+ if (pkt_len < min_len) goto browse_length_error;
/* Copyback the PDU */
change_path_rsp->pdu = pdu;
/* Read the status */
BE_STREAM_TO_UINT8(change_path_rsp->status, p);
/* Read the number of items in folder */
BE_STREAM_TO_UINT32(change_path_rsp->num_items, p);
- pkt_len_read += 5;
AVRC_TRACE_DEBUG("%s pdu %d status %d item count %d", __func__,
change_path_rsp->pdu, change_path_rsp->status,
@@ -399,6 +415,8 @@
set_br_pl_rsp->pdu = pdu;
/* Read the status */
+ min_len += 10;
+ if (pkt_len < min_len) goto browse_length_error;
BE_STREAM_TO_UINT8(set_br_pl_rsp->status, p);
if (set_br_pl_rsp->status != AVRC_STS_NO_ERROR) {
@@ -415,7 +433,6 @@
"%s AVRC_PDU_SET_BROWSED_PLAYER status %d items %d cs %d depth %d",
__func__, set_br_pl_rsp->status, set_br_pl_rsp->num_items,
set_br_pl_rsp->charset_id, set_br_pl_rsp->folder_depth);
- pkt_len_read += 10;
set_br_pl_rsp->p_folders = (tAVRC_NAME*)osi_malloc(
set_br_pl_rsp->num_items * sizeof(tAVRC_NAME));
@@ -423,13 +440,14 @@
/* Read each of the folder in the depth */
for (uint32_t i = 0; i < set_br_pl_rsp->folder_depth; i++) {
tAVRC_NAME* folder_name = &(set_br_pl_rsp->p_folders[i]);
+ min_len += 2 + folder_name->str_len;
+ if (pkt_len < min_len) goto browse_length_error;
BE_STREAM_TO_UINT16(folder_name->str_len, p);
AVRC_TRACE_DEBUG("%s AVRC_PDU_SET_BROWSED_PLAYER item: %d len: %d",
__func__, i, folder_name->str_len);
folder_name->p_str =
(uint8_t*)osi_malloc((folder_name->str_len + 1) * sizeof(uint8_t));
BE_STREAM_TO_ARRAY(p, folder_name->p_str, folder_name->str_len);
- pkt_len_read += (2 + folder_name->str_len);
}
break;
}
@@ -438,12 +456,13 @@
AVRC_TRACE_ERROR("%s pdu %d not handled", __func__, pdu);
}
- if (pkt_len != pkt_len_read) {
- AVRC_TRACE_ERROR("%s finished pkt_len %d pkt_len_read %d", __func__,
- pkt_len, pkt_len_read);
- return AVRC_STS_BAD_CMD;
- }
return status;
+
+browse_length_error:
+ android_errorWriteLog(0x534e4554, "111451066");
+ AVRC_TRACE_WARNING("%s: invalid parameter length %d: must be at least %d",
+ __func__, pkt_len, min_len);
+ return AVRC_STS_BAD_CMD;
}
/*******************************************************************************
