hevc: Fix memory leak related to a53_caption data

Signed-off-by: Will Kelleher <wkelleher@gogoair.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

libavcodec/hevc.c

@@ -3155,6 +3155,8 @@ static av_cold int hevc_init_context(AVCodecContext *avctx)
     s->context_initialized = 1;
     s->eos = 0;
 
+    ff_hevc_reset_sei(s);
+
     return 0;
 
 fail:

libavcodec/hevc.h

@@ -1054,6 +1054,15 @@ void ff_hevc_hls_mvd_coding(HEVCContext *s, int x0, int y0, int log2_cb_size);
 int ff_hevc_encode_nal_vps(HEVCVPS *vps, unsigned int id,
                            uint8_t *buf, int buf_size);
 
+/**
+ * Reset SEI values that are stored on the Context.
+ * e.g. Caption data that was extracted during NAL
+ * parsing.
+ *
+ * @param s HEVCContext.
+ */
+void ff_hevc_reset_sei(HEVCContext *s);
+
 extern const uint8_t ff_hevc_qpel_extra_before[4];
 extern const uint8_t ff_hevc_qpel_extra_after[4];
 extern const uint8_t ff_hevc_qpel_extra[4];

libavcodec/hevc_parser.c

@@ -211,6 +211,8 @@ static inline int parse_nal_units(AVCodecParserContext *s, const uint8_t *buf,
 
     h->avctx = avctx;
 
+    ff_hevc_reset_sei(h);
+
     if (!buf_size)
         return 0;
 

libavcodec/hevc_sei.c

@@ -373,3 +373,9 @@ int ff_hevc_decode_nal_sei(HEVCContext *s)
     } while (more_rbsp_data(&s->HEVClc->gb));
     return 1;
 }
+
+void ff_hevc_reset_sei(HEVCContext *s)
+{
+    s->a53_caption_size = 0;
+    av_freep(&s->a53_caption);
+}