[llvm] [llvm-objcopy] Add possibility to verify .note section format (PR #90458)

[James Henderson via llvm-commits]

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@@ -0,0 +1,45 @@
+## Verify that --add-section warns on invalid note sections.
+
+## Add [namesz, descsz, type, name, desc] for a build id.
+
+## Notes should be padded on 8 bytes.
+# RUN: printf "\x04\x00\x00\x00" >  %t-miss-padding-note.bin
+# RUN: printf "\x07\x00\x00\x00" >> %t-miss-padding-note.bin
+# RUN: printf "\x03\x00\x00\x00" >> %t-miss-padding-note.bin
+# RUN: printf "GNU\x00"          >> %t-miss-padding-note.bin
+# RUN: printf "\x0c\x0d\x0e"     >> %t-miss-padding-note.bin
+
+## The namesz field bit is incorrect.
+# RUN: printf "\x08\x00\x00\x00" >  %t-invalid-size-note.bin
+# RUN: printf "\x07\x00\x00\x00" >> %t-invalid-size-note.bin
+# RUN: printf "\x03\x00\x00\x00" >> %t-invalid-size-note.bin
+# RUN: printf "GNU\x00"          >> %t-invalid-size-note.bin
+# RUN: printf "\x0c\x0d\x0e\x00" >> %t-invalid-size-note.bin
+
+## Missing type field.
+# RUN: printf "\x08\x00\x00\x00" >  %t-short-note.bin
+# RUN: printf "\x07\x00\x00\x00" >> %t-short-note.bin
+
+# RUN: yaml2obj %s -o %t.o
+
+## Test each invalid note.
+# RUN: not llvm-objcopy --add-section=.note.miss.padding=%t-miss-padding-note.bin %t.o %t-with-note.o 2>&1 | FileCheck --check-prefix=CHECK-MISS-PADDING %s
+# CHECK-MISS-PADDING: .note.miss.padding data size must be a multiple of 4 bytes
+
+# RUN: not llvm-objcopy --add-section=.note.invalid.size=%t-invalid-size-note.bin %t.o %t-with-note.o 2>&1 | FileCheck --check-prefix=CHECK-INVALID-SIZE %s
+# CHECK-INVALID-SIZE: .note.invalid.size data size is incompatible with the content of the name and description size fields: expecting 28, found 20
+
+# RUN: not llvm-objcopy --add-section=.note.short=%t-short-note.bin %t.o %t-with-note.o 2>&1 | FileCheck --check-prefix=CHECK-SHORT %s
+# CHECK-SHORT: .note.short data must be either empty or at least 12 bytes long
+
+## Test that verification can be disabled.
+# RUN: llvm-objcopy --add-section=.note.short=%t-short-note.bin --no-verify-note-sections %t.o %t-with-note.o
+
+## Test that last argument has precedence.
+# RUN: llvm-objcopy --add-section=.note.short=%t-short-note.bin --verify-note-sections --no-verify-note-sections %t.o %t-with-note.o
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jh7370 wrote:

I'd do this test case both ways round, since this is no different to doing it without `--verify-note-sections`.

https://github.com/llvm/llvm-project/pull/90458