specs: document ELF note-merging semantics for dlopen and package metadata - #222
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xnox wants to merge 2 commits into
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specs: document ELF note-merging semantics for dlopen and package metadata#222xnox wants to merge 2 commits into
xnox wants to merge 2 commits into
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…adata Linkers concatenate same-named sections from multiple input files, so a linked binary can carry multiple .note.dlopen or .note.package notes even when each producer emitted only one. Parsers must therefore iterate over one or more Note structures rather than assuming a single note. Add a "Guidance on parsing ELF sections" section to both specs describing this, with a readelf example. Make the two specs share the same parsing procedure: this behavior is forced by the ELF spec and by the binutils ld and LLVM lld implementations, and was already the long-standing status quo for dlopen metadata (one note per dependency or one combined note), so the package metadata spec now inherits it. For package metadata, note the SCA/SBOM/vulnerability-matching implication: multiple notes indicate a likely statically linked binary composed from several packages, all of which must be enumerated.
poettering
reviewed
Jul 8, 2026
poettering
reviewed
Jul 8, 2026
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lgtm, but be more precise regarding the padding/alignment, as suggested |
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Linkers concatenate same-named sections from multiple input files, so a
linked binary can carry multiple .note.dlopen or .note.package notes even
when each producer emitted only one. Parsers must therefore iterate over
one or more Note structures rather than assuming a single note.
Add a "Guidance on parsing ELF sections" section to both specs describing
this, with a readelf example. Make the two specs share the same parsing
procedure: this behavior is forced by the ELF spec and by the binutils ld
and LLVM lld implementations, and was already the long-standing status quo
for dlopen metadata (one note per dependency or one combined note), so the
package metadata spec now inherits it.
For package metadata, note the SCA/SBOM/vulnerability-matching implication:
multiple notes indicate a likely statically linked binary composed from
several packages, all of which must be enumerated.