Fix: fix and refactor st41 possible errors (#972)

* Fix possible null pointer reference in app_tx_fmd_init

* Fix: coveriy out of band issue

* Increate quality of tx_fastmetadata_session_build_packet code

* coverity fix:  fixing less-than-zero comparison

* add st41 context app multithread access error

* Add error message when the st41 functionality of RxTx app detects
multithread access to the contex
app resource, which should not be shared.

Fixes: c43152d

Co-developed-by: Aleksandr Ivanov <aleksandr.ivanov@intel.com>
Co-developed-by: Kolelis, Szymon <szymon.kolelis@intel.com>

app/src/parse_json.c

@@ -1255,7 +1255,7 @@ static int st_json_parse_tx_fmd(int idx, json_object* fmd_obj,
       st_json_object_object_get(fmd_obj, "fastmetadata_data_item_type");
   if (fmd_dit_obj) {
     uint32_t fmd_dit = json_object_get_int(fmd_dit_obj);
-    if (fmd_dit < 0 || fmd_dit > 0x3fffff) {
+    if (fmd_dit > 0x3fffff) {
       err("%s, invalid fastmetadata_data_item_type 0x%x\n", __func__, fmd_dit);
       return -ST_JSON_NOT_VALID;
     }
@@ -1269,8 +1269,10 @@ static int st_json_parse_tx_fmd(int idx, json_object* fmd_obj,
   /* parse fmd data item K-bit */
   json_object* fmd_k_bit_obj = st_json_object_object_get(fmd_obj, "fastmetadata_k_bit");
   if (fmd_k_bit_obj) {
+    /* assign to uint and check if the value more then 1
+     * (the value should be in range of [0,1]) */
     uint8_t fmd_k_bit = json_object_get_int(fmd_k_bit_obj);
-    if (fmd_k_bit < 0 || fmd_k_bit > 1) {
+    if (fmd_k_bit > 1) {
       err("%s, invalid fastmetadata_k_bit 0x%x\n", __func__, fmd_k_bit);
       return -ST_JSON_NOT_VALID;
     }

app/src/tx_fastmetadata_app.c

@@ -94,21 +94,29 @@ static void* app_tx_fmd_frame_thread(void* arg) {
   info("%s(%d), start\n", __func__, idx);
   while (!s->st41_app_thread_stop) {
     st_pthread_mutex_lock(&s->st41_wake_mutex);
-    producer_idx = s->framebuff_producer_idx;
-    framebuff = &s->framebuffs[producer_idx];
-    if (ST_TX_FRAME_FREE != framebuff->stat) {
-      /* not in free */
-      if (!s->st41_app_thread_stop)
+    framebuff = &s->framebuffs[s->framebuff_producer_idx];
+
+    if (framebuff->stat != ST_TX_FRAME_FREE) {
+      if (!s->st41_app_thread_stop) {
         st_pthread_cond_wait(&s->st41_wake_cond, &s->st41_wake_mutex);
+      }
       st_pthread_mutex_unlock(&s->st41_wake_mutex);
       continue;
     }
+
+    producer_idx = s->framebuff_producer_idx;
     st_pthread_mutex_unlock(&s->st41_wake_mutex);
 
     struct st41_frame* frame_addr = st41_tx_get_framebuffer(s->handle, producer_idx);
     app_tx_fmd_build_frame(s, frame_addr);
 
     st_pthread_mutex_lock(&s->st41_wake_mutex);
+    if (producer_idx != s->framebuff_producer_idx) {
+      err("%s(%d), Apps can't share the context app structure\n", __func__, idx);
+      st_pthread_mutex_unlock(&s->st41_wake_mutex);
+      return NULL;
+    }
+
     framebuff->size = sizeof(*frame_addr);
     framebuff->stat = ST_TX_FRAME_READY;
     /* point to next */
@@ -440,8 +448,8 @@ static int app_tx_fmd_init(struct st_app_context* ctx,
   ops.notify_rtp_done = app_tx_fmd_rtp_done;
   ops.framebuff_cnt = s->framebuff_cnt;
   ops.fps = fmd ? fmd->info.fmd_fps : ST_FPS_P59_94;
-  ops.fmd_dit = fmd->info.fmd_dit;
-  ops.fmd_k_bit = fmd->info.fmd_k_bit;
+  ops.fmd_dit = fmd ? fmd->info.fmd_dit : 0;
+  ops.fmd_k_bit = fmd ? fmd->info.fmd_k_bit : 0;
   s->st41_pcap_input = false;
   ops.type = fmd ? fmd->info.type : ST41_TYPE_FRAME_LEVEL;
   ops.interlaced = fmd ? fmd->info.interlaced : false;

lib/src/st2110/st_tx_fastmetadata_session.c

@@ -389,15 +389,20 @@ static int tx_fastmetadata_session_update_redundant(
 
 static void tx_fastmetadata_session_build_packet(
     struct st_tx_fastmetadata_session_impl* s, struct rte_mbuf* pkt) {
-  struct mt_udp_hdr* hdr;
+  struct st41_fmd_hdr* hdr;
   struct rte_ipv4_hdr* ipv4;
   struct rte_udp_hdr* udp;
   struct st41_rtp_hdr* rtp;
 
-  hdr = rte_pktmbuf_mtod(pkt, struct mt_udp_hdr*);
+  if (rte_pktmbuf_data_len(pkt) < sizeof(*hdr)) {
+    err("%s: packet is less than fmd hdr size", __func__);
+    return;
+  }
+
+  hdr = rte_pktmbuf_mtod(pkt, struct st41_fmd_hdr*);
   ipv4 = &hdr->ipv4;
   udp = &hdr->udp;
-  rtp = (struct st41_rtp_hdr*)&udp[1];
+  rtp = &hdr->rtp;
 
   /* copy the hdr: eth, ip, udp */
   rte_memcpy(&hdr->eth, &s->hdr[MTL_SESSION_PORT_P].eth, sizeof(hdr->eth));
@@ -417,7 +422,6 @@ static void tx_fastmetadata_session_build_packet(
   rtp->base.tmstamp = htonl(s->pacing.rtp_time_stamp);
 
   /* Set place for payload just behind rtp header */
-  uint8_t* payload = (uint8_t*)&rtp[1];
   struct st_frame_trans* frame_info = &s->st41_frames[s->st41_frame_idx];
   uint32_t offset = s->st41_pkt_idx * s->max_pkt_len;
   void* src_addr = frame_info->addr + offset;
@@ -426,6 +430,12 @@ static void tx_fastmetadata_session_build_packet(
   uint16_t data_item_length =
       (data_item_length_bytes + 3) / 4; /* expressed in number of 4-byte words */
 
+  if (rte_pktmbuf_data_len(pkt) < sizeof(*hdr) + data_item_length) {
+    err("%s: packet doesn't contain RTP payload", __func__);
+    return;
+  }
+
+  uint8_t* payload = (uint8_t*)(rtp + 1);
   if (!(data_item_length_bytes > s->max_pkt_len)) {
     int offset = 0;
     for (int i = 0; i < data_item_length_bytes; i++) {