dvbsubdec: check memory allocations and propagate errors

libavcodec/dvbsubdec.c

@@ -832,7 +832,7 @@ static void dvbsub_parse_pixel_data_block(AVCodecContext *avctx, DVBSubObjectDis
 
 }
 
-static void dvbsub_parse_object_segment(AVCodecContext *avctx,
+static int dvbsub_parse_object_segment(AVCodecContext *avctx,
                                        const uint8_t *buf, int buf_size)
 {
     DVBSubContext *ctx = avctx->priv_data;
@@ -852,7 +852,7 @@ static void dvbsub_parse_object_segment(AVCodecContext *avctx,
     object = get_object(ctx, object_id);
 
     if (!object)
-        return;
+        return AVERROR_INVALIDDATA;
 
     coding_method = ((*buf) >> 2) & 3;
     non_modifying_color = ((*buf++) >> 1) & 1;
@@ -865,7 +865,7 @@ static void dvbsub_parse_object_segment(AVCodecContext *avctx,
 
         if (buf + top_field_len + bottom_field_len > buf_end) {
             av_log(avctx, AV_LOG_ERROR, "Field data size too large\n");
-            return;
+            return AVERROR_INVALIDDATA;
         }
 
         for (display = object->display_list; display; display = display->object_list_next) {
@@ -889,9 +889,10 @@ static void dvbsub_parse_object_segment(AVCodecContext *avctx,
         av_log(avctx, AV_LOG_ERROR, "Unknown object coding %d\n", coding_method);
     }
 
+    return 0;
 }
 
-static void dvbsub_parse_clut_segment(AVCodecContext *avctx,
+static int dvbsub_parse_clut_segment(AVCodecContext *avctx,
                                      const uint8_t *buf, int buf_size)
 {
     DVBSubContext *ctx = avctx->priv_data;
@@ -921,6 +922,8 @@ static void dvbsub_parse_clut_segment(AVCodecContext *avctx,
 
     if (!clut) {
         clut = av_malloc(sizeof(DVBSubCLUT));
+        if (!clut)
+            return AVERROR(ENOMEM);
 
         memcpy(clut, &default_clut, sizeof(DVBSubCLUT));
 
@@ -937,7 +940,7 @@ static void dvbsub_parse_clut_segment(AVCodecContext *avctx,
 
         if (depth == 0) {
             av_log(avctx, AV_LOG_ERROR, "Invalid clut depth 0x%x!\n", *buf);
-            return;
+            return AVERROR_INVALIDDATA;
         }
 
         full_range = (*buf++) & 1;
@@ -971,10 +974,12 @@ static void dvbsub_parse_clut_segment(AVCodecContext *avctx,
         if (depth & 0x20)
             clut->clut256[entry_id] = RGBA(r,g,b,255 - alpha);
     }
+
+    return 0;
 }
 
 
-static void dvbsub_parse_region_segment(AVCodecContext *avctx,
+static int dvbsub_parse_region_segment(AVCodecContext *avctx,
                                        const uint8_t *buf, int buf_size)
 {
     DVBSubContext *ctx = avctx->priv_data;
@@ -987,7 +992,7 @@ static void dvbsub_parse_region_segment(AVCodecContext *avctx,
     int fill;
 
     if (buf_size < 10)
-        return;
+        return AVERROR_INVALIDDATA;
 
     region_id = *buf++;
 
@@ -995,6 +1000,8 @@ static void dvbsub_parse_region_segment(AVCodecContext *avctx,
 
     if (!region) {
         region = av_mallocz(sizeof(DVBSubRegion));
+        if (!region)
+            return AVERROR(ENOMEM);
 
         region->id = region_id;
 
@@ -1015,6 +1022,8 @@ static void dvbsub_parse_region_segment(AVCodecContext *avctx,
         region->buf_size = region->width * region->height;
 
         region->pbuf = av_malloc(region->buf_size);
+        if (!region->pbuf)
+            return AVERROR(ENOMEM);
 
         fill = 1;
     }
@@ -1054,6 +1063,8 @@ static void dvbsub_parse_region_segment(AVCodecContext *avctx,
 
         if (!object) {
             object = av_mallocz(sizeof(DVBSubObject));
+            if (!object)
+                return AVERROR(ENOMEM);
 
             object->id = object_id;
             object->next = ctx->object_list;
@@ -1063,6 +1074,8 @@ static void dvbsub_parse_region_segment(AVCodecContext *avctx,
         object->type = (*buf) >> 6;
 
         display = av_mallocz(sizeof(DVBSubObjectDisplay));
+        if (!display)
+            return AVERROR(ENOMEM);
 
         display->object_id = object_id;
         display->region_id = region_id;
@@ -1083,9 +1096,11 @@ static void dvbsub_parse_region_segment(AVCodecContext *avctx,
         display->object_list_next = object->display_list;
         object->display_list = display;
     }
+
+    return 0;
 }
 
-static void dvbsub_parse_page_segment(AVCodecContext *avctx,
+static int dvbsub_parse_page_segment(AVCodecContext *avctx,
                                      const uint8_t *buf, int buf_size)
 {
     DVBSubContext *ctx = avctx->priv_data;
@@ -1097,7 +1112,7 @@ static void dvbsub_parse_page_segment(AVCodecContext *avctx,
     int page_state;
 
     if (buf_size < 1)
-        return;
+        return AVERROR_INVALIDDATA;
 
     ctx->time_out = *buf++;
     page_state = ((*buf++) >> 2) & 3;
@@ -1124,8 +1139,11 @@ static void dvbsub_parse_page_segment(AVCodecContext *avctx,
             display = display->next;
         }
 
-        if (!display)
+        if (!display) {
             display = av_mallocz(sizeof(DVBSubRegionDisplay));
+            if (!display)
+                return AVERROR(ENOMEM);
+        }
 
         display->region_id = region_id;
 
@@ -1151,6 +1169,7 @@ static void dvbsub_parse_page_segment(AVCodecContext *avctx,
         av_free(display);
     }
 
+    return 0;
 }
 
 
@@ -1204,6 +1223,8 @@ static void save_display_set(DVBSubContext *ctx)
     if (x_pos >= 0) {
 
         pbuf = av_malloc(width * height * 4);
+        if (!pbuf)
+            return AVERROR(ENOMEM);
 
         for (display = ctx->display_list; display; display = display->next) {
             region = get_region(ctx, display->region_id);
@@ -1249,7 +1270,7 @@ static void save_display_set(DVBSubContext *ctx)
 }
 #endif
 
-static void dvbsub_parse_display_definition_segment(AVCodecContext *avctx,
+static int dvbsub_parse_display_definition_segment(AVCodecContext *avctx,
                                                    const uint8_t *buf,
                                                    int buf_size)
 {
@@ -1258,19 +1279,19 @@ static void dvbsub_parse_display_definition_segment(AVCodecContext *avctx,
     int dds_version, info_byte;
 
     if (buf_size < 5)
-        return;
+        return AVERROR_INVALIDDATA;
 
     info_byte   = bytestream_get_byte(&buf);
     dds_version = info_byte >> 4;
     if (display_def && display_def->version == dds_version)
-        return; // already have this display definition version
+        return 0; // already have this display definition version
 
     if (!display_def) {
         display_def             = av_mallocz(sizeof(*display_def));
+        if (!display_def)
+            return AVERROR(ENOMEM);
         ctx->display_definition = display_def;
     }
-    if (!display_def)
-        return;
 
     display_def->version = dds_version;
     display_def->x       = 0;
@@ -1279,7 +1300,7 @@ static void dvbsub_parse_display_definition_segment(AVCodecContext *avctx,
     display_def->height  = bytestream_get_be16(&buf) + 1;
 
     if (buf_size < 13)
-        return;
+        return AVERROR_INVALIDDATA;
 
     if (info_byte & 1<<3) { // display_window_flag
         display_def->x = bytestream_get_be16(&buf);
@@ -1287,6 +1308,8 @@ static void dvbsub_parse_display_definition_segment(AVCodecContext *avctx,
         display_def->width  = bytestream_get_be16(&buf) - display_def->x + 1;
         display_def->height = bytestream_get_be16(&buf) - display_def->y + 1;
     }
+
+    return 0;
 }
 
 static int dvbsub_display_end_segment(AVCodecContext *avctx, const uint8_t *buf,
@@ -1411,7 +1434,7 @@ static int dvbsub_decode(AVCodecContext *avctx,
 
     if (buf_size <= 6 || *buf != 0x0f) {
         av_dlog(avctx, "incomplete or broken packet");
-        return -1;
+        return AVERROR_INVALIDDATA;
     }
 
     p = buf;
@@ -1432,30 +1455,35 @@ static int dvbsub_decode(AVCodecContext *avctx,
 
         if (page_id == ctx->composition_id || page_id == ctx->ancillary_id ||
             ctx->composition_id == -1 || ctx->ancillary_id == -1) {
+            int ret = 0;
             switch (segment_type) {
             case DVBSUB_PAGE_SEGMENT:
-                dvbsub_parse_page_segment(avctx, p, segment_length);
+                ret = dvbsub_parse_page_segment(avctx, p, segment_length);
                 break;
             case DVBSUB_REGION_SEGMENT:
-                dvbsub_parse_region_segment(avctx, p, segment_length);
+                ret = dvbsub_parse_region_segment(avctx, p, segment_length);
                 break;
             case DVBSUB_CLUT_SEGMENT:
-                dvbsub_parse_clut_segment(avctx, p, segment_length);
+                ret = dvbsub_parse_clut_segment(avctx, p, segment_length);
                 break;
             case DVBSUB_OBJECT_SEGMENT:
-                dvbsub_parse_object_segment(avctx, p, segment_length);
+                ret = dvbsub_parse_object_segment(avctx, p, segment_length);
                 break;
             case DVBSUB_DISPLAYDEFINITION_SEGMENT:
-                dvbsub_parse_display_definition_segment(avctx, p, segment_length);
+                ret = dvbsub_parse_display_definition_segment(avctx, p,
+                                                              segment_length);
                 break;
             case DVBSUB_DISPLAY_SEGMENT:
-                *data_size = dvbsub_display_end_segment(avctx, p, segment_length, sub);
+                ret = dvbsub_display_end_segment(avctx, p, segment_length, sub);
+                *data_size = ret;
                 break;
             default:
                 av_dlog(avctx, "Subtitling segment type 0x%x, page id %d, length %d\n",
                         segment_type, page_id, segment_length);
                 break;
             }
+            if (ret < 0)
+                return ret;
         }
 
         p += segment_length;