[issue36856] faulthandler._stack_overflow doesn't work on x86-linux with KPTI enabled

STINNER Victor added the comment: Thanks Xi Ruoyao, I applied your fix to 3.7 and master branches. -- resolution: -> fixed stage: patch review -> resolved status: open -> closed ___ Python tracker _

[issue36856] faulthandler._stack_overflow doesn't work on x86-linux with KPTI enabled

miss-islington added the comment: New changeset 1062cf71faa14b90185cf159877083910df10f27 by Miss Islington (bot) in branch '3.7': bpo-36856: Handle possible overflow in faulthandler_stack_overflow (GH-13205) https://github.com/python/cpython/commit/1062cf71faa14b90185cf159877083910df10f27 -

[issue36856] faulthandler._stack_overflow doesn't work on x86-linux with KPTI enabled

Change by miss-islington : -- pull_requests: +13511 pull_request: https://github.com/python/cpython/pull/13605 ___ Python tracker ___ __

[issue36856] faulthandler._stack_overflow doesn't work on x86-linux with KPTI enabled

STINNER Victor added the comment: New changeset 6236c9823ef3e8e2229b0598d3d8189adf5e00f2 by Victor Stinner (Xi Ruoyao) in branch 'master': bpo-36856: Handle possible overflow in faulthandler_stack_overflow (GH-13205) https://github.com/python/cpython/commit/6236c9823ef3e8e2229b0598d3d8189adf5

[issue36856] faulthandler._stack_overflow doesn't work on x86-linux with KPTI enabled

Pablo Galindo Salgado added the comment: Are uintptr_t overflow/underflow semantics a defined behavior? -- nosy: +pablogsal ___ Python tracker ___

[issue36856] faulthandler._stack_overflow doesn't work on x86-linux with KPTI enabled

Xi Ruoyao added the comment: > Are uintptr_t overflow/underflow semantics a defined behavior? Yes. Unlike signed overflow, unsigned overflow is defined to be 2's complement. The problem is this overflow results a wrong stack pointer limit and breaks _stack_overflow. -- __

[issue36856] faulthandler._stack_overflow doesn't work on x86-linux with KPTI enabled

Change by Xi Ruoyao : -- keywords: +patch pull_requests: +13116 stage: -> patch review ___ Python tracker ___ ___ Python-bugs-list

[issue36856] faulthandler._stack_overflow doesn't work on x86-linux with KPTI enabled

Change by SilentGhost : -- nosy: +vstinner ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.pytho

[issue36856] faulthandler._stack_overflow doesn't work on x86-linux with KPTI enabled

New submission from Xi Ruoyao : In faulthandler.c STACK_OVERFLOW_MAX_SIZE is defined to 100 * 1024 * 1024 (100MB). But recently KPTI has been applied to mitigate Meltdown (CVE-2017-5754) so the userspace stack pointer may be very close to 0x on Linux systems with 32-bit x86. For exa