File ffmpeg-4-CVE-2026-64833.patch of Package A_tw-ffmpeg-4

From 385ac2fadcb4394ec4f65e5c4d3d24003e090f36 Mon Sep 17 00:00:00 2001
From: Michael Niedermayer <michael@niedermayer.cc>
Date: Tue, 30 Jun 2026 00:11:50 +0200
Subject: [PATCH] avformat/spdifenc: bound DTS core_size against the packet
 size in the HD path

Fixes: out of array read
Fixes: yBSax492UIB9
Fixes: 482d98f69b2 (spdifenc: IEC 61937 encapsulation of DTS-HD for HDMI)
Found-by: Pavel Kohout (Aisle Research)
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
(cherry picked from commit 6f80e2765492700622596af720534cef33dd31b4)
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
---
 libavformat/spdifenc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libavformat/spdifenc.c b/libavformat/spdifenc.c
index ab3f73da0d..16eebda01c 100644
--- a/libavformat/spdifenc.c
+++ b/libavformat/spdifenc.c
@@ -225,7 +225,7 @@ static int spdif_header_dts4(AVFormatContext *s, AVPacket *pkt, int core_size,
              * (dtshd_fallback == 0) */
             ctx->dtshd_skip = 1;
     }
-    if (ctx->dtshd_skip && core_size) {
+    if (ctx->dtshd_skip && core_size && core_size <= pkt->size) {
         pkt_size = core_size;
         if (ctx->dtshd_fallback >= 0)
             --ctx->dtshd_skip;
-- 
2.49.0