fix: zero-fill NOBITS sections in ELF loader#1379
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ludfjig wants to merge 1 commit intohyperlight-dev:mainfrom
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fix: zero-fill NOBITS sections in ELF loader#1379ludfjig wants to merge 1 commit intohyperlight-dev:mainfrom
ludfjig wants to merge 1 commit intohyperlight-dev:mainfrom
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Some linkers emit PT_LOAD segments where filesz == memsz but contain .bss sections whose VMA range overlaps with file bytes from unrelated sections. The loader copies the full segment verbatim, leaving .bss with stale data instead of zeros. Collect NOBITS section ranges (excluding .tbss) during ELF parsing and zero-fill them after loading PT_LOAD segments. Signed-off-by: Ludvig Liljenberg <4257730+ludfjig@users.noreply.github.com> Co-authored-by: danbugs <danilochiarlone@gmail.com>
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This was referenced Apr 15, 2026
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Apr 15, 2026
| // Zero-fill NOBITS sections (e.g. .bss) that were not already | ||
| // covered by the filesz < memsz zeroing above. | ||
| for &(addr, size) in &self.nobits_ranges { | ||
| let sh_start = (addr - base_va) as usize; |
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Nit: I am not sure if it can happen, but is this guaranteed to not fail? Maybe a checked sub is better here
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Some linkers emit PT_LOAD segments where filesz == memsz but contain .bss sections whose VMA range overlaps with file bytes from unrelated sections. The loader copies the full segment verbatim, leaving .bss with stale data instead of zeros.
Collect NOBITS section ranges (excluding .tbss) during ELF parsing and zero-fill them after loading PT_LOAD segments.
This is needed for unikraft