From bd57f72f396d0ad7368c784eb89e9bd89fba5037 Mon Sep 17 00:00:00 2001
From: Ryan Oldenburg <ryan@guzba.com>
Date: Wed, 8 Jun 2022 20:04:18 -0500
Subject: [PATCH] ensure we only ever see one sof

---
 src/pixie/fileformats/jpeg.nim | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/src/pixie/fileformats/jpeg.nim b/src/pixie/fileformats/jpeg.nim
index 442661a..c91fcf9 100644
--- a/src/pixie/fileformats/jpeg.nim
+++ b/src/pixie/fileformats/jpeg.nim
@@ -68,6 +68,7 @@ type
     len, pos: int
     bitsBuffered: int
     bitBuffer: uint32
+    foundSOF: bool
     imageHeight, imageWidth: int
     progressive: bool
     quantizationTables: array[4, array[64, uint8]]
@@ -243,6 +244,10 @@ proc decodeDHT(state: var DecoderState) =
 
 proc decodeSOF0(state: var DecoderState) =
   ## Decode start of Frame
+  if state.foundSOF:
+    failInvalid()
+  state.foundSOF = true
+
   var len = state.readUint16be().int - 2
 
   let precision = state.readUint8()