From ca2209d67af0a73fe0edb2fce1cea2445dbfd8db Mon Sep 17 00:00:00 2001
From: "Ronald S. Bultje" <rsbultje@gmail.com>
Date: Wed, 24 May 2017 11:46:07 -0400
Subject: [PATCH] hevc: fix race condition in max_ra/seq_decode.

These variables are shared between frame threads, but they are updated
post-setup_finished() if a EOB/EOS slice type occurs. Moving the EOB/EOS
slices to the next frame thread instance (by parsing them leading into
the next picture instead of trailing behind the last picture) effectively
prevents this race condition.

This fixes tsan failures on hevc-conformance-NoOutPrior_A_Qualcomm_1.
---
 libavcodec/hevc_parser.c |  2 +-
 libavcodec/hevcdec.c     | 12 ++++++++++--
 2 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/libavcodec/hevc_parser.c b/libavcodec/hevc_parser.c
index c72b1465f1..2b58eb62fe 100644
--- a/libavcodec/hevc_parser.c
+++ b/libavcodec/hevc_parser.c
@@ -267,7 +267,7 @@ static int hevc_find_frame_end(AVCodecParserContext *s, const uint8_t *buf,
 
         nut = (pc->state64 >> 2 * 8 + 1) & 0x3F;
         // Beginning of access unit
-        if ((nut >= HEVC_NAL_VPS && nut <= HEVC_NAL_AUD) || nut == HEVC_NAL_SEI_PREFIX ||
+        if ((nut >= HEVC_NAL_VPS && nut <= HEVC_NAL_EOB_NUT) || nut == HEVC_NAL_SEI_PREFIX ||
             (nut >= 41 && nut <= 44) || (nut >= 48 && nut <= 55)) {
             if (pc->frame_start_found) {
                 pc->frame_start_found = 0;
diff --git a/libavcodec/hevcdec.c b/libavcodec/hevcdec.c
index ee001fd9f2..fc9a5b749e 100644
--- a/libavcodec/hevcdec.c
+++ b/libavcodec/hevcdec.c
@@ -2890,6 +2890,7 @@ fail:
 static int decode_nal_units(HEVCContext *s, const uint8_t *buf, int length)
 {
     int i, ret = 0;
+    int eos_at_start = 1;
 
     s->ref = NULL;
     s->last_eos = s->eos;
@@ -2907,8 +2908,15 @@ static int decode_nal_units(HEVCContext *s, const uint8_t *buf, int length)
 
     for (i = 0; i < s->pkt.nb_nals; i++) {
         if (s->pkt.nals[i].type == HEVC_NAL_EOB_NUT ||
-            s->pkt.nals[i].type == HEVC_NAL_EOS_NUT)
-            s->eos = 1;
+            s->pkt.nals[i].type == HEVC_NAL_EOS_NUT) {
+            if (eos_at_start) {
+                s->last_eos = 1;
+            } else {
+                s->eos = 1;
+            }
+        } else {
+            eos_at_start = 0;
+        }
     }
 
     /* decode the NAL units */