From abef977ad5bc77a6d20df9f44ce1319b074e6c73 Mon Sep 17 00:00:00 2001
From: Alessandro Ros <aler9.dev@gmail.com>
Date: Thu, 27 Mar 2025 11:38:28 +0100
Subject: [PATCH] improve NALU size limit errors (#741)

---
 pkg/format/rtpav1/decoder.go       | 5 +++--
 pkg/format/rtpav1/decoder_test.go  | 2 +-
 pkg/format/rtph264/decoder.go      | 5 +++--
 pkg/format/rtph264/decoder_test.go | 2 +-
 pkg/format/rtph265/decoder.go      | 5 +++--
 pkg/format/rtph265/decoder_test.go | 2 +-
 6 files changed, 12 insertions(+), 9 deletions(-)

diff --git a/pkg/format/rtpav1/decoder.go b/pkg/format/rtpav1/decoder.go
index 11791d7b..fb24dd2e 100644
--- a/pkg/format/rtpav1/decoder.go
+++ b/pkg/format/rtpav1/decoder.go
@@ -143,11 +143,12 @@ func (d *Decoder) Decode(pkt *rtp.Packet) ([][]byte, error) {
 	l := len(obus)
 
 	if (d.frameBufferLen + l) > av1.MaxOBUsPerTemporalUnit {
+		errCount := d.frameBufferLen + l
 		d.frameBuffer = nil
 		d.frameBufferLen = 0
 		d.frameBufferSize = 0
-		return nil, fmt.Errorf("OBU count exceeds maximum allowed (%d)",
-			av1.MaxOBUsPerTemporalUnit)
+		return nil, fmt.Errorf("OBU count (%d) exceeds maximum allowed (%d)",
+			errCount, av1.MaxOBUsPerTemporalUnit)
 	}
 
 	addSize := 0
diff --git a/pkg/format/rtpav1/decoder_test.go b/pkg/format/rtpav1/decoder_test.go
index 5e1b722d..4c43b263 100644
--- a/pkg/format/rtpav1/decoder_test.go
+++ b/pkg/format/rtpav1/decoder_test.go
@@ -52,7 +52,7 @@ func TestDecoderErrorLimit(t *testing.T) {
 		})
 	}
 
-	require.EqualError(t, err, "OBU count exceeds maximum allowed (10)")
+	require.EqualError(t, err, "OBU count (11) exceeds maximum allowed (10)")
 }
 
 func TestDecodeErrorMissingPacket(t *testing.T) {
diff --git a/pkg/format/rtph264/decoder.go b/pkg/format/rtph264/decoder.go
index f5a37e61..8ccc781b 100644
--- a/pkg/format/rtph264/decoder.go
+++ b/pkg/format/rtph264/decoder.go
@@ -215,11 +215,12 @@ func (d *Decoder) Decode(pkt *rtp.Packet) ([][]byte, error) {
 	l := len(nalus)
 
 	if (d.frameBufferLen + l) > h264.MaxNALUsPerAccessUnit {
+		errCount := d.frameBufferLen + l
 		d.frameBuffer = nil
 		d.frameBufferLen = 0
 		d.frameBufferSize = 0
-		return nil, fmt.Errorf("NALU count exceeds maximum allowed (%d)",
-			h264.MaxNALUsPerAccessUnit)
+		return nil, fmt.Errorf("NALU count (%d) exceeds maximum allowed (%d)",
+			errCount, h264.MaxNALUsPerAccessUnit)
 	}
 
 	addSize := 0
diff --git a/pkg/format/rtph264/decoder_test.go b/pkg/format/rtph264/decoder_test.go
index b092d205..b4dd2b99 100644
--- a/pkg/format/rtph264/decoder_test.go
+++ b/pkg/format/rtph264/decoder_test.go
@@ -241,7 +241,7 @@ func TestDecoderErrorLimit(t *testing.T) {
 		})
 	}
 
-	require.EqualError(t, err, "NALU count exceeds maximum allowed (25)")
+	require.EqualError(t, err, "NALU count (26) exceeds maximum allowed (25)")
 }
 
 func TestDecodeErrorMissingPacket(t *testing.T) {
diff --git a/pkg/format/rtph265/decoder.go b/pkg/format/rtph265/decoder.go
index 781f3ca1..4777a06c 100644
--- a/pkg/format/rtph265/decoder.go
+++ b/pkg/format/rtph265/decoder.go
@@ -174,11 +174,12 @@ func (d *Decoder) Decode(pkt *rtp.Packet) ([][]byte, error) {
 	l := len(nalus)
 
 	if (d.frameBufferLen + l) > h265.MaxNALUsPerAccessUnit {
+		errCount := d.frameBufferLen + l
 		d.frameBuffer = nil
 		d.frameBufferLen = 0
 		d.frameBufferSize = 0
-		return nil, fmt.Errorf("NALU count exceeds maximum allowed (%d)",
-			h265.MaxNALUsPerAccessUnit)
+		return nil, fmt.Errorf("NALU count (%d) exceeds maximum allowed (%d)",
+			errCount, h265.MaxNALUsPerAccessUnit)
 	}
 
 	addSize := 0
diff --git a/pkg/format/rtph265/decoder_test.go b/pkg/format/rtph265/decoder_test.go
index dcb50f55..c6599328 100644
--- a/pkg/format/rtph265/decoder_test.go
+++ b/pkg/format/rtph265/decoder_test.go
@@ -58,7 +58,7 @@ func TestDecoderErrorLimit(t *testing.T) {
 		})
 	}
 
-	require.EqualError(t, err, "NALU count exceeds maximum allowed (21)")
+	require.EqualError(t, err, "NALU count (22) exceeds maximum allowed (21)")
 }
 
 func TestDecodeErrorMissingPacket(t *testing.T) {