From caa9b4ff89c00591a0730d2cc5db8693da8dffba Mon Sep 17 00:00:00 2001
From: Michael Niedermayer <michael@niedermayer.cc>
Date: Tue, 2 Apr 2019 20:27:13 +0200
Subject: [PATCH] avcodec/agm: Check that there is available input in
 read_code()

Fixes: Timeout (46sec -> 7ms)
Fixes: 14030/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_AGM_fuzzer-5721258760601600

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
---
 libavcodec/agm.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/libavcodec/agm.c b/libavcodec/agm.c
index 7dcfaff4adc..332e33897c0 100644
--- a/libavcodec/agm.c
+++ b/libavcodec/agm.c
@@ -103,6 +103,9 @@ static int read_code(GetBitContext *gb, int *oskip, int *level, int *map, int mo
 {
     int len = 0, skip = 0, max;
 
+    if (get_bits_left(gb) < 2)
+        return AVERROR_INVALIDDATA;
+
     if (show_bits(gb, 2)) {
         switch (show_bits(gb, 4)) {
         case 1:
-- 
2.39.5