[llvm] 6f44bb7 - [Object] Ensure header size not to underflow in `OffloadBinary::create`

[Antonio Frighetto via llvm-commits]

Author: Antonio Frighetto
Date: 2024-03-22T15:45:23+01:00
New Revision: 6f44bb7717897191be25aa01161831c67cdf5b84

URL: https://github.com/llvm/llvm-project/commit/6f44bb7717897191be25aa01161831c67cdf5b84
DIFF: https://github.com/llvm/llvm-project/commit/6f44bb7717897191be25aa01161831c67cdf5b84.diff

LOG: [Object] Ensure header size not to underflow in `OffloadBinary::create`

Prevent potential integer underflows when header size is not valid.

Fixes: https://github.com/llvm/llvm-project/issues/86280.

Added: 
    

Modified: 
    llvm/lib/Object/OffloadBinary.cpp

Removed: 
    


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diff  --git a/llvm/lib/Object/OffloadBinary.cpp b/llvm/lib/Object/OffloadBinary.cpp
index 4ab6536dc90b52..6e9f8bed513c19 100644
--- a/llvm/lib/Object/OffloadBinary.cpp
+++ b/llvm/lib/Object/OffloadBinary.cpp
@@ -189,7 +189,10 @@ OffloadBinary::create(MemoryBufferRef Buf) {
     return errorCodeToError(object_error::parse_failed);
 
   if (TheHeader->Size > Buf.getBufferSize() ||
-      TheHeader->EntryOffset > TheHeader->Size - sizeof(Entry) ||
+      TheHeader->Size < sizeof(Entry) || TheHeader->Size < sizeof(Header))
+    return errorCodeToError(object_error::unexpected_eof);
+
+  if (TheHeader->EntryOffset > TheHeader->Size - sizeof(Entry) ||
       TheHeader->EntrySize > TheHeader->Size - sizeof(Header))
     return errorCodeToError(object_error::unexpected_eof);