[PATCH] D38777: [wasm] readSection: Avoid reading past eof (fixes oss-fuzz #3219)

[Sam Clegg via Phabricator via llvm-commits]

sbc100 added inline comments.


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Comment at: lib/Object/WasmObjectFile.cpp:190
   Ptr += Size;
+  if (Ptr > Eof)
+    return make_error<StringError>("Section too large",
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Perhaps do this before the ArrayRef is created and before Ptr is incremented?

`if (Ptr + Size > Eof) `


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Comment at: test/tools/llvm-dwarfdump/X86/fuzzer.test:2
+RUN: not llvm-dwarfdump %S/Inputs/oss-fuzz-3219 2>&1 | FileCheck --check-prefix=FUZZ3219 %s
+FUZZ3219: oss-fuzz-3219: Invalid data was encountered while parsing the file
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Any reason this lives in 'X86'?


https://reviews.llvm.org/D38777