Fix OOB read in process_l2cap_cmd

Bug: 74202041
Bug: 74196706
Bug: 74201143
Test: manual
Change-Id: Ic25f7f3777d0375f76cc91e4d129b1636f1c388d

diff --git a/stack/l2cap/l2c_main.cc b/stack/l2cap/l2c_main.cc
index 390cd2c..2574f88 100644 (file)
--- a/stack/l2cap/l2c_main.cc
+++ b/stack/l2cap/l2c_main.cc
@@ -321,9 +321,11 @@ static void process_l2cap_cmd(tL2C_LCB* p_lcb, uint8_t* p, uint16_t pkt_len) {
     switch (cmd_code) {
       case L2CAP_CMD_REJECT:
         uint16_t rej_reason;
+        if (p + 2 > p_next_cmd) return;
         STREAM_TO_UINT16(rej_reason, p);
         if (rej_reason == L2CAP_CMD_REJ_MTU_EXCEEDED) {
           uint16_t rej_mtu;
+          if (p + 2 > p_next_cmd) return;
           STREAM_TO_UINT16(rej_mtu, p);
           /* What to do with the MTU reject ? We have negotiated an MTU. For now
            * we will ignore it and let a higher protocol timeout take care of it
@@ -333,6 +335,7 @@ static void process_l2cap_cmd(tL2C_LCB* p_lcb, uint8_t* p, uint16_t pkt_len) {
         }
         if (rej_reason == L2CAP_CMD_REJ_INVALID_CID) {
           uint16_t lcid, rcid;
+          if (p + 4 > p_next_cmd) return;
           STREAM_TO_UINT16(rcid, p);
           STREAM_TO_UINT16(lcid, p);
 
@@ -368,6 +371,7 @@ static void process_l2cap_cmd(tL2C_LCB* p_lcb, uint8_t* p, uint16_t pkt_len) {
 
       case L2CAP_CMD_CONN_REQ: {
         uint16_t rcid;
+        if (p + 4 > p_next_cmd) return;
         STREAM_TO_UINT16(con_info.psm, p);
         STREAM_TO_UINT16(rcid, p);
         tL2C_RCB* p_rcb = l2cu_find_rcb_by_psm(con_info.psm);
@@ -401,6 +405,7 @@ static void process_l2cap_cmd(tL2C_LCB* p_lcb, uint8_t* p, uint16_t pkt_len) {
 
       case L2CAP_CMD_CONN_RSP: {
         uint16_t lcid;
+        if (p + 8 > p_next_cmd) return;
         STREAM_TO_UINT16(con_info.remote_cid, p);
         STREAM_TO_UINT16(lcid, p);
         STREAM_TO_UINT16(con_info.l2cap_result, p);
@@ -434,6 +439,7 @@ static void process_l2cap_cmd(tL2C_LCB* p_lcb, uint8_t* p, uint16_t pkt_len) {
         uint16_t cfg_rej_len = 0;
 
         uint16_t lcid;
+        if (p + 4 > p_next_cmd) return;
         STREAM_TO_UINT16(lcid, p);
         STREAM_TO_UINT16(cfg_info.flags, p);
 
@@ -445,22 +451,26 @@ static void process_l2cap_cmd(tL2C_LCB* p_lcb, uint8_t* p, uint16_t pkt_len) {
 
         while (p < p_cfg_end) {
           uint8_t cfg_code, cfg_len;
+          if (p + 2 > p_next_cmd) return;
           STREAM_TO_UINT8(cfg_code, p);
           STREAM_TO_UINT8(cfg_len, p);
 
           switch (cfg_code & 0x7F) {
             case L2CAP_CFG_TYPE_MTU:
               cfg_info.mtu_present = true;
+              if (p + 2 > p_next_cmd) return;
               STREAM_TO_UINT16(cfg_info.mtu, p);
               break;
 
             case L2CAP_CFG_TYPE_FLUSH_TOUT:
               cfg_info.flush_to_present = true;
+              if (p + 2 > p_next_cmd) return;
               STREAM_TO_UINT16(cfg_info.flush_to, p);
               break;
 
             case L2CAP_CFG_TYPE_QOS:
               cfg_info.qos_present = true;
+              if (p + 2 + 5 * 4 > p_next_cmd) return;
               STREAM_TO_UINT8(cfg_info.qos.qos_flags, p);
               STREAM_TO_UINT8(cfg_info.qos.service_type, p);
               STREAM_TO_UINT32(cfg_info.qos.token_rate, p);
@@ -472,6 +482,7 @@ static void process_l2cap_cmd(tL2C_LCB* p_lcb, uint8_t* p, uint16_t pkt_len) {
 
             case L2CAP_CFG_TYPE_FCR:
               cfg_info.fcr_present = true;
+              if (p + 3 + 3 * 2 > p_next_cmd) return;
               STREAM_TO_UINT8(cfg_info.fcr.mode, p);
               STREAM_TO_UINT8(cfg_info.fcr.tx_win_sz, p);
               STREAM_TO_UINT8(cfg_info.fcr.max_transmit, p);
@@ -482,11 +493,13 @@ static void process_l2cap_cmd(tL2C_LCB* p_lcb, uint8_t* p, uint16_t pkt_len) {
 
             case L2CAP_CFG_TYPE_FCS:
               cfg_info.fcs_present = true;
+              if (p + 1 > p_next_cmd) return;
               STREAM_TO_UINT8(cfg_info.fcs, p);
               break;
 
             case L2CAP_CFG_TYPE_EXT_FLOW:
               cfg_info.ext_flow_spec_present = true;
+              if (p + 2 + 2 + 3 * 4 > p_next_cmd) return;
               STREAM_TO_UINT8(cfg_info.ext_flow_spec.id, p);
               STREAM_TO_UINT8(cfg_info.ext_flow_spec.stype, p);
               STREAM_TO_UINT16(cfg_info.ext_flow_spec.max_sdu_size, p);
@@ -533,6 +546,7 @@ static void process_l2cap_cmd(tL2C_LCB* p_lcb, uint8_t* p, uint16_t pkt_len) {
       case L2CAP_CMD_CONFIG_RSP: {
         uint8_t* p_cfg_end = p + cmd_len;
         uint16_t lcid;
+        if (p + 6 > p_next_cmd) return;
         STREAM_TO_UINT16(lcid, p);
         STREAM_TO_UINT16(cfg_info.flags, p);
         STREAM_TO_UINT16(cfg_info.result, p);
@@ -543,22 +557,26 @@ static void process_l2cap_cmd(tL2C_LCB* p_lcb, uint8_t* p, uint16_t pkt_len) {
 
         while (p < p_cfg_end) {
           uint8_t cfg_code, cfg_len;
+          if (p + 2 > p_next_cmd) return;
           STREAM_TO_UINT8(cfg_code, p);
           STREAM_TO_UINT8(cfg_len, p);
 
           switch (cfg_code & 0x7F) {
             case L2CAP_CFG_TYPE_MTU:
               cfg_info.mtu_present = true;
+              if (p + 2 > p_next_cmd) return;
               STREAM_TO_UINT16(cfg_info.mtu, p);
               break;
 
             case L2CAP_CFG_TYPE_FLUSH_TOUT:
               cfg_info.flush_to_present = true;
+              if (p + 2 > p_next_cmd) return;
               STREAM_TO_UINT16(cfg_info.flush_to, p);
               break;
 
             case L2CAP_CFG_TYPE_QOS:
               cfg_info.qos_present = true;
+              if (p + 2 + 5 * 4 > p_next_cmd) return;
               STREAM_TO_UINT8(cfg_info.qos.qos_flags, p);
               STREAM_TO_UINT8(cfg_info.qos.service_type, p);
               STREAM_TO_UINT32(cfg_info.qos.token_rate, p);
@@ -570,6 +588,7 @@ static void process_l2cap_cmd(tL2C_LCB* p_lcb, uint8_t* p, uint16_t pkt_len) {
 
             case L2CAP_CFG_TYPE_FCR:
               cfg_info.fcr_present = true;
+              if (p + 3 + 3 * 2 > p_next_cmd) return;
               STREAM_TO_UINT8(cfg_info.fcr.mode, p);
               STREAM_TO_UINT8(cfg_info.fcr.tx_win_sz, p);
               STREAM_TO_UINT8(cfg_info.fcr.max_transmit, p);
@@ -580,11 +599,13 @@ static void process_l2cap_cmd(tL2C_LCB* p_lcb, uint8_t* p, uint16_t pkt_len) {
 
             case L2CAP_CFG_TYPE_FCS:
               cfg_info.fcs_present = true;
+              if (p + 1 > p_next_cmd) return;
               STREAM_TO_UINT8(cfg_info.fcs, p);
               break;
 
             case L2CAP_CFG_TYPE_EXT_FLOW:
               cfg_info.ext_flow_spec_present = true;
+              if (p + 2 + 2 + 3 * 4 > p_next_cmd) return;
               STREAM_TO_UINT8(cfg_info.ext_flow_spec.id, p);
               STREAM_TO_UINT8(cfg_info.ext_flow_spec.stype, p);
               STREAM_TO_UINT16(cfg_info.ext_flow_spec.max_sdu_size, p);
@@ -616,6 +637,7 @@ static void process_l2cap_cmd(tL2C_LCB* p_lcb, uint8_t* p, uint16_t pkt_len) {
 
       case L2CAP_CMD_DISC_REQ: {
         uint16_t lcid, rcid;
+        if (p + 4 > p_next_cmd) return;
         STREAM_TO_UINT16(lcid, p);
         STREAM_TO_UINT16(rcid, p);
 
@@ -633,6 +655,7 @@ static void process_l2cap_cmd(tL2C_LCB* p_lcb, uint8_t* p, uint16_t pkt_len) {
 
       case L2CAP_CMD_DISC_RSP: {
         uint16_t lcid, rcid;
+        if (p + 4 > p_next_cmd) return;
         STREAM_TO_UINT16(rcid, p);
         STREAM_TO_UINT16(lcid, p);
 
@@ -662,6 +685,7 @@ static void process_l2cap_cmd(tL2C_LCB* p_lcb, uint8_t* p, uint16_t pkt_len) {
 
       case L2CAP_CMD_INFO_REQ: {
         uint16_t info_type;
+        if (p + 2 > p_next_cmd) return;
         STREAM_TO_UINT16(info_type, p);
         l2cu_send_peer_info_rsp(p_lcb, id, info_type);
         break;
@@ -675,6 +699,7 @@ static void process_l2cap_cmd(tL2C_LCB* p_lcb, uint8_t* p, uint16_t pkt_len) {
         }
 
         uint16_t info_type, result;
+        if (p + 4 > p_next_cmd) return;
         STREAM_TO_UINT16(info_type, p);
         STREAM_TO_UINT16(result, p);
 
@@ -682,6 +707,7 @@ static void process_l2cap_cmd(tL2C_LCB* p_lcb, uint8_t* p, uint16_t pkt_len) {
 
         if ((info_type == L2CAP_EXTENDED_FEATURES_INFO_TYPE) &&
             (result == L2CAP_INFO_RESP_RESULT_SUCCESS)) {
+          if (p + 4 > p_next_cmd) return;
           STREAM_TO_UINT32(p_lcb->peer_ext_fea, p);
 
 #if (L2CAP_NUM_FIXED_CHNLS > 0)