classification
Title: Interpreter crash upon accessing frame.f_restricted of a frame from a dead thread
Type: crash Stage: resolved
Components: Interpreter Core Versions: Python 2.7
process
Status: closed Resolution: duplicate
Dependencies: Superseder: 2.7 core crashes with generator.gi_frame.f_restricted
View: 22851
Assigned To: Nosy List: anselm.kruis, serhiy.storchaka
Priority: normal Keywords:

Created on 2014-07-12 16:31 by anselm.kruis, last changed 2018-10-26 08:14 by serhiy.storchaka. This issue is now closed.

Files
File name Uploaded Description Edit
crash_on_f_restricted.py anselm.kruis, 2014-07-12 16:31 test programm that eventually causes a crash
Messages (2)
msg222852 - (view) Author: Anselm Kruis (anselm.kruis) * Date: 2014-07-12 16:31
If you store a reference to a frame from a dead thread and then access 
frame.f_restricted python eventually crashed.

I didn't investigate this bug in depth. Here is my preliminary explanation.

The access of frame.f_restricted causes a call of PyFrame_IsRestricted(f). 

PyFrame_IsRestricted is a macro and expands to 
((f)->f_builtins != (f)->f_tstate->interp->builtins) 

Now, if the thread that created f is already dead, the f_tstate points to an invalid structure. Depending on the content of the memory the access of f_tstate->interp causes an access violation. I use a Win32 debug build to reliable reproduce the issue.
msg328521 - (view) Author: Serhiy Storchaka (serhiy.storchaka) * (Python committer) Date: 2018-10-26 08:14
Thank you for your report Anselm. Seems this bug is fixed in issue22851.
History
Date User Action Args
2018-10-26 08:14:40serhiy.storchakasetstatus: open -> closed

superseder: 2.7 core crashes with generator.gi_frame.f_restricted

nosy: + serhiy.storchaka
messages: + msg328521
resolution: duplicate
stage: resolved
2014-07-12 16:31:09anselm.kruiscreate