From 4abf3e1264bdc0c89fed172b8657dc886e41552c Mon Sep 17 00:00:00 2001
From: Adam Lesinski <adam@runloop.ai>
Date: Thu, 14 Aug 2025 12:08:27 -0700
Subject: [PATCH] Fix buffer-overflow in sha256 string construction

Need to leave room for the last null-byte.
---
 src/tools/sha256file.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/tools/sha256file.cpp b/src/tools/sha256file.cpp
index 2878db8e..47ad7979 100644
--- a/src/tools/sha256file.cpp
+++ b/src/tools/sha256file.cpp
@@ -103,7 +103,7 @@ string sha256sum(const char *fn) {
         }
     }
     SHA256_Final(sha, &ctx);
-    char res[SHA256_DIGEST_LENGTH * 2];
+    char res[SHA256_DIGEST_LENGTH * 2 + 1];
     for (int i = 0; i < SHA256_DIGEST_LENGTH; i++)
         sprintf(res + (i * 2), "%02x", sha[i]);
     return "sha256:" + std::string(res, SHA256_DIGEST_LENGTH * 2);