Fix dyldcache parsing for iOS 18 beta changes #23033
Merged
Conversation
This file contains 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
So it can represent the size of big dyld caches, which as of iOS 18.0 beta start to need 33 bits.
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
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Outdated suggestions cannot be applied.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.
Description
iOS 18 beta introduces a couple new fields to the dyldcache header, the purpose of which is still unclear to me (and it reflects on the bad names i gave 'em) but broke the heuristics for detecting the subcache info format. This change leverages the first of the two new fields to update the format detection logic.
The other big issue was that r2's Mach-O size was represented as an
int, but the new dyldcache have a logical combined size which now requires 33 bits 😅 , so our bounds checking code was overreacting. Fixed by bringing thesizefield up tout64capacity.