dwarf: Fix SEGV when accessing uninitialized skeleton CU #475
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When processing malformed DWARF data, specifically a compile unit where a top-level DIE attribute requires indirect address resolution (e.g., DW_AT_GNU_dwo_id using DW_FORM_addrx), Bloaty would crash. This occurred because `ReadTopLevelDIE` was called before `skeleton_` was initialized in `CU::ReadHeader`, leading to a null pointer dereference in `ReadIndirectAddress`. This patch moves the initialization of `skeleton_` to the beginning of `CU::ReadHeader` to ensure it is available when reading top-level attributes. Fixes google#402
This was referenced Jan 5, 2026
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@haberman This is a very small fix that fixes at least 3 reported issues. |
haberman
approved these changes
Jan 6, 2026
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When processing malformed DWARF data, specifically a compile unit
where a top-level DIE attribute requires indirect address resolution
(e.g., DW_AT_GNU_dwo_id using DW_FORM_addrx), Bloaty would crash.
This occurred because
ReadTopLevelDIEwas called beforeskeleton_was initialized in
CU::ReadHeader, leading to a null pointerdereference in
ReadIndirectAddress.This patch moves the initialization of
skeleton_to the beginningof
CU::ReadHeaderto ensure it is available when reading top-levelattributes.
Fixes #402
Fixes #409
Fixes #463