dwarf: Fix SEGV when accessing uninitialized skeleton CU#475
Merged
EricRahm merged 2 commits intogoogle:mainfrom Jan 6, 2026
Merged
dwarf: Fix SEGV when accessing uninitialized skeleton CU#475EricRahm merged 2 commits intogoogle:mainfrom
EricRahm merged 2 commits intogoogle:mainfrom
Conversation
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
Collaborator
Author
|
@haberman This is a very small fix that fixes at least 3 reported issues. |
haberman
approved these changes
Jan 6, 2026
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
2 participants
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
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