Prevent Out of bounds read in llcp code
Modifies llcp_util.cc & llcp_link.cc to fix the OOB issues.
Test: Nfc Enable/Disable, Android Beam, Tag reading
Bug: 114237888
Bug: 114238578
Bug: 111699773
Bug: 111660010
Merged-In: Ie28888ddb9a5a2605ae32a27e3dba01c35ab3913
Change-Id: Ie28888ddb9a5a2605ae32a27e3dba01c35ab3913
(cherry picked from commit 23eb85a028780af14f617e27938540a52c18a8d5)
(cherry picked from commit fe340aad0291879de8d3b33a9bdff4d6a5c8d36a)
diff --git a/src/nfc/llcp/llcp_link.cc b/src/nfc/llcp/llcp_link.cc
index cebabba..8a5ddf2 100644
--- a/src/nfc/llcp/llcp_link.cc
+++ b/src/nfc/llcp/llcp_link.cc
@@ -1131,7 +1131,7 @@
agf_length = p_agf->len;
p = (uint8_t*)(p_agf + 1) + p_agf->offset;
- while (agf_length > 0) {
+ while (agf_length >= LLCP_PDU_HEADER_SIZE) {
/* get length of PDU */
p_pdu_length = p;
BE_STREAM_TO_UINT16(pdu_length, p);
diff --git a/src/nfc/llcp/llcp_util.cc b/src/nfc/llcp/llcp_util.cc
index 8b582d8..973a1b9 100644
--- a/src/nfc/llcp/llcp_util.cc
+++ b/src/nfc/llcp/llcp_util.cc
@@ -26,6 +26,7 @@
#include <android-base/stringprintf.h>
#include <base/logging.h>
+#include <log/log.h>
#include "bt_types.h"
#include "gki.h"
@@ -49,20 +50,24 @@
bool llcp_util_parse_link_params(uint16_t length, uint8_t* p_bytes) {
uint8_t param_type, param_len, *p = p_bytes;
- while (length) {
+ while (length >= 2) {
BE_STREAM_TO_UINT8(param_type, p);
- length--;
+ BE_STREAM_TO_UINT8(param_len, p);
+ if (length < param_len + 2) {
+ android_errorWriteLog(0x534e4554, "114238578");
+ LOG(ERROR) << StringPrintf("Bad LTV's");
+ return false;
+ }
+ length -= param_len + 2;
switch (param_type) {
case LLCP_VERSION_TYPE:
- BE_STREAM_TO_UINT8(param_len, p);
BE_STREAM_TO_UINT8(llcp_cb.lcb.peer_version, p);
DLOG_IF(INFO, nfc_debug_enabled)
<< StringPrintf("Peer Version - 0x%02X", llcp_cb.lcb.peer_version);
break;
case LLCP_MIUX_TYPE:
- BE_STREAM_TO_UINT8(param_len, p);
BE_STREAM_TO_UINT16(llcp_cb.lcb.peer_miu, p);
llcp_cb.lcb.peer_miu &= LLCP_MIUX_MASK;
llcp_cb.lcb.peer_miu += LLCP_DEFAULT_MIU;
@@ -71,14 +76,12 @@
break;
case LLCP_WKS_TYPE:
- BE_STREAM_TO_UINT8(param_len, p);
BE_STREAM_TO_UINT16(llcp_cb.lcb.peer_wks, p);
DLOG_IF(INFO, nfc_debug_enabled)
<< StringPrintf("Peer WKS - 0x%04X", llcp_cb.lcb.peer_wks);
break;
case LLCP_LTO_TYPE:
- BE_STREAM_TO_UINT8(param_len, p);
BE_STREAM_TO_UINT8(llcp_cb.lcb.peer_lto, p);
llcp_cb.lcb.peer_lto *= LLCP_LTO_UNIT; /* 10ms unit */
DLOG_IF(INFO, nfc_debug_enabled)
@@ -86,7 +89,6 @@
break;
case LLCP_OPT_TYPE:
- BE_STREAM_TO_UINT8(param_len, p);
BE_STREAM_TO_UINT8(llcp_cb.lcb.peer_opt, p);
DLOG_IF(INFO, nfc_debug_enabled)
<< StringPrintf("Peer OPT - 0x%02X", llcp_cb.lcb.peer_opt);
@@ -94,17 +96,9 @@
default:
LOG(ERROR) << StringPrintf("Unexpected type 0x%x", param_type);
- BE_STREAM_TO_UINT8(param_len, p);
p += param_len;
break;
}
-
- if (length >= param_len + 1)
- length -= param_len + 1;
- else {
- LOG(ERROR) << StringPrintf("Bad LTV's");
- return false;
- }
}
return true;
}
@@ -474,13 +468,19 @@
p_params->sn[0] = 0;
p_params->sn[1] = 0;
- while (length) {
+ while (length >= 2) {
BE_STREAM_TO_UINT8(param_type, p);
- length--;
+ BE_STREAM_TO_UINT8(param_len, p);
+ /* check remaining lengh */
+ if (length < param_len + 2) {
+ android_errorWriteLog(0x534e4554, "111660010");
+ LOG(ERROR) << StringPrintf("Bad LTV's");
+ return LLCP_STATUS_FAIL;
+ }
+ length -= param_len + 2;
switch (param_type) {
case LLCP_MIUX_TYPE:
- BE_STREAM_TO_UINT8(param_len, p);
BE_STREAM_TO_UINT16(p_params->miu, p);
p_params->miu &= LLCP_MIUX_MASK;
p_params->miu += LLCP_DEFAULT_MIU;
@@ -490,7 +490,6 @@
break;
case LLCP_RW_TYPE:
- BE_STREAM_TO_UINT8(param_len, p);
BE_STREAM_TO_UINT8(p_params->rw, p);
p_params->rw &= 0x0F;
@@ -499,8 +498,6 @@
break;
case LLCP_SN_TYPE:
- BE_STREAM_TO_UINT8(param_len, p);
-
if (param_len == 0) {
/* indicate that SN type is included without SN */
p_params->sn[1] = LLCP_SN_TYPE;
@@ -519,18 +516,9 @@
default:
LOG(ERROR) << StringPrintf("Unexpected type 0x%x", param_type);
- BE_STREAM_TO_UINT8(param_len, p);
p += param_len;
break;
}
-
- /* check remaining lengh */
- if (length >= param_len + 1) {
- length -= param_len + 1;
- } else {
- LOG(ERROR) << StringPrintf("Bad LTV's");
- return LLCP_STATUS_FAIL;
- }
}
return LLCP_STATUS_SUCCESS;
}
@@ -607,13 +595,18 @@
*p_miu = LLCP_DEFAULT_MIU;
*p_rw = LLCP_DEFAULT_RW;
- while (length) {
+ while (length >= 2) {
BE_STREAM_TO_UINT8(param_type, p);
- length--;
+ BE_STREAM_TO_UINT8(param_len, p);
+ if (length < param_len + 2) {
+ android_errorWriteLog(0x534e4554, "114237888");
+ LOG(ERROR) << StringPrintf("Bad LTV's");
+ return LLCP_STATUS_FAIL;
+ }
+ length -= param_len + 2;
switch (param_type) {
case LLCP_MIUX_TYPE:
- BE_STREAM_TO_UINT8(param_len, p);
BE_STREAM_TO_UINT16((*p_miu), p);
(*p_miu) &= LLCP_MIUX_MASK;
(*p_miu) += LLCP_DEFAULT_MIU;
@@ -623,7 +616,6 @@
break;
case LLCP_RW_TYPE:
- BE_STREAM_TO_UINT8(param_len, p);
BE_STREAM_TO_UINT8((*p_rw), p);
(*p_rw) &= 0x0F;
@@ -633,17 +625,9 @@
default:
LOG(ERROR) << StringPrintf("Unexpected type 0x%x", param_type);
- BE_STREAM_TO_UINT8(param_len, p);
p += param_len;
break;
}
-
- if (length >= param_len + 1)
- length -= param_len + 1;
- else {
- LOG(ERROR) << StringPrintf("Bad LTV's");
- return LLCP_STATUS_FAIL;
- }
}
return LLCP_STATUS_SUCCESS;
}
