Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

mmap failure returning 0x00 instead of MAP_FAILED #3218

Closed
gimbling-away opened this issue Dec 10, 2023 · 0 comments · Fixed by #3219
Closed

mmap failure returning 0x00 instead of MAP_FAILED #3218

gimbling-away opened this issue Dec 10, 2023 · 0 comments · Fixed by #3219
Assignees
@saethlin

Comments

@gimbling-away
Copy link

gimbling-away commented Dec 10, 2023 •
edited

Upon failure, mmap is supposed to return MAP_FAILED, not nullptr.

miri/src/shims/unix/mem.rs

Line 75 in 12c868a

return Ok(Scalar::from_maybe_pointer(Pointer::null(), this));

Currently mmap returns null pointer in miri.

Is this intentional or accidental?
@saethlin saethlin linked a pull request Dec 10, 2023 that will close this issue
Return MAP_FAILED when mmap fails #3219
Merged
@saethlin saethlin self-assigned this Dec 10, 2023
@saethlin saethlin mentioned this issue Dec 10, 2023
Merged
bors added a commit that referenced this issue Dec 10, 2023
@bors
Auto merge of #3219 - saethlin:map-failed, r=RalfJung
02d5495 
Return MAP_FAILED when mmap fails

I don't properly remember why we ended up with a hodgepodge of return values, but #3218 correctly points out that we are supposed to return `MAP_FAILED`. This should fix that return value and also add sufficient tests to prevent making a similar mistake.
RalfJung pushed a commit to RalfJung/rust that referenced this issue Dec 17, 2023
@bors
Auto merge of rust-lang#3219 - saethlin:map-failed, r=RalfJung
5ade852 
Return MAP_FAILED when mmap fails

I don't properly remember why we ended up with a hodgepodge of return values, but rust-lang/miri#3218 correctly points out that we are supposed to return `MAP_FAILED`. This should fix that return value and also add sufficient tests to prevent making a similar mistake.
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Assignees

@saethlin saethlin

Labels
None yet
Projects
None yet
Milestone
No milestone
Development

Successfully merging a pull request may close this issue.

Return MAP_FAILED when mmap fails saethlin/miri
2 participants
@saethlin @gimbling-away