Fix #2782: heap-use-after-free in expand.cpp

[glebm]

Selector stack got popped during eval, resulting in extender deletion.

[xzyfer]

Appveyor build timed out. Kicked off a rebuild.

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On Tue., 4 Dec. 2018, 8:26 am Gleb Mazovetskiy ***@***.*** wrote: Selector stack got popped during eval, resulting in extender deletion. ------------------------------ You can view, comment on, or merge this pull request online at: #2784 Commit Summary - Fix #2782: heap-use-after-free in expand.cpp File Changes - *M* src/expand.cpp <https://github.com/sass/libsass/pull/2784/files#diff-0> (2) Patch Links: - https://github.com/sass/libsass/pull/2784.patch - https://github.com/sass/libsass/pull/2784.diff — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#2784>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AAjZWDQB76UOg-AtdIXJB3_WHByXtHVCks5u1ZbrgaJpZM4Y_cim> .

[glebm]

AppVeyor is broken because of @mgreter's recent changes. The fix is in #2775.

[glebm]

By the way, the broken windows build is tracked in #2776

[glebm]

Now green.

[xzyfer]

Thanks for following up. Is there anyway to scan or lint for this kind of mistake across th codebase. The introduction of _Obj and _Ptr types was fairly jarring and I suspect more of these have slipped through the cracks.

[glebm]

I'm hoping that #2785 will at least make it obvious.
I don't think an automatic lint is possible here (as _Ptr is better for performance when it is safe).

I'm following this Rust Sass compiler closely btw: https://github.com/kaj/rsass.

[xzyfer]

Oh cool. I've started hacking on a rust port a couple times but never really had the time to commit to it. Excited to see where it goes.

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On Thu., 6 Dec. 2018, 2:52 pm Gleb Mazovetskiy ***@***.*** wrote: I'm hoping that #2785 <#2785> will at least make it obvious. I don't think an automatic lint is possible here (as _Ptr is better for performance when it is safe). I'm following this Rust Sass compiler closely btw: https://github.com/kaj/rsass. — You are receiving this because you modified the open/close state. Reply to this email directly, view it on GitHub <#2784 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AAjZWCrfq4X1b7_8Oz3OafPq0YmorRckks5u2JRvgaJpZM4Y_cim> .