avoid integer overflow for cache-limit #620
Open
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
ossilator
reviewed
Jun 21, 2023
Without this, "mb * 1024 * 1024" overflows for mb >= 2048. The result is then cast into size_t, which is unsigned and usually a 64-bit integer. The end result is, that the cache is now basically unlimited. Fix this by making sure that the multiplication operated on 64-bit values.
ossilator
reviewed
Jun 21, 2023
There was a problem hiding this comment.
"operate_s_" in the commit message.
also, the statement isn't true on 32-bit systems.
hmm. so pedantically, this is all wrong anyway. it shouldn't be size_t, but off64_t or some such. but i suspect that the code is full of such bugs anyway, so whatever. "nobody" still builds on 32-bit machines anyway.
some error handling would be nice, though. but that's a separate thing.
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Outdated suggestions cannot be applied.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.
Without this, "mb * 1024 * 1024" overflows for mb >= 2048. The result is then cast into size_t, which is unsigned and usually a 64-bit integer. The end result is, that the cache is now basically unlimited.
Fix this by making mb a size_t as well to avoid the overflow.