From 063a881e7a5cd57156dbd0c9b6ad4d30f7023e55 Mon Sep 17 00:00:00 2001
From: Kimball Thurston <kdt3rd@gmail.com>
Date: Thu, 2 Feb 2023 14:04:12 +1300
Subject: [PATCH] Fix missing guard check (#1329)

Addresses OSS-FUZZ
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=52730

Signed-off-by: Kimball Thurston <kdt3rd@gmail.com>
---
 src/lib/OpenEXRCore/internal_huf.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/src/lib/OpenEXRCore/internal_huf.c b/src/lib/OpenEXRCore/internal_huf.c
index fa769c9ef..92fcc3233 100644
--- a/src/lib/OpenEXRCore/internal_huf.c
+++ b/src/lib/OpenEXRCore/internal_huf.c
@@ -1280,9 +1280,21 @@ fasthuf_initialize (
             codeCount[codeLen]++;
         }
         else if (codeLen == (uint64_t) LONG_ZEROCODE_RUN)
+        {
+            if (currByte >= topByte)
+            {
+                if (pctxt)
+                    pctxt->print_error (
+                        pctxt,
+                        EXR_ERR_CORRUPT_CHUNK,
+                        "Error decoding Huffman table (Truncated table data).");
+                return EXR_ERR_CORRUPT_CHUNK;
+            }
+
             symbol +=
                 fasthuf_read_bits (8, &currBits, &currBitCount, &currByte) +
                 SHORTEST_LONG_RUN - 1;
+        }
         else
             symbol += codeLen - SHORT_ZEROCODE_RUN + 1;