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Description of problem:
libreswan uses pthreads to call pam. When this call is canceled, there is a cleanup callback. This callback is not called when compiled with -fexceptions.
If -fexceptions is specified on GLIBC based GNU/Linux systems, pthread_cleanup_push() et.al. are implemented using GLIBC's unwinder.
Unfortunately, it seems to fail when unwinding from a custom built shared object (is the object built correctly?).
Removing -fexceptions causes pthread_cleanup_push() et.al. to be implemented using setjmp / longjmp which seems to be more robust.
This seems related to this unresolved upstream bug:
https://sourceware.org/bugzilla/show_bug.cgi?id=14266
Our problem case was extracted into the following example code that shows the bug:
https://github.com/cagney/pthread-cancel
If -fexceptions is specified on GLIBC based GNU/Linux systems,
pthread_cleanup_push() et.al. are implemented using GLIBC's unwinder.
Unfortunately, it seems to fail when unwinding from a custom built
shared object (is the object built correctly?).
Removing -fexceptions causes pthread_cleanup_push() et.al. to be
implemented using setjmp / longjmp which seems to be more robust.
Would you please post a backtrace at the time of cancellation (with debuginfo packages installed), and the exact versions of the packages involved.
Note that PAM does not support thread cancellation. There will be resource leaks if you cancel a thread while it is executing PAM functions. If you need to cancel PAM operations, you should spawn a separate process for that.
Description of problem: libreswan uses pthreads to call pam. When this call is canceled, there is a cleanup callback. This callback is not called when compiled with -fexceptions. If -fexceptions is specified on GLIBC based GNU/Linux systems, pthread_cleanup_push() et.al. are implemented using GLIBC's unwinder. Unfortunately, it seems to fail when unwinding from a custom built shared object (is the object built correctly?). Removing -fexceptions causes pthread_cleanup_push() et.al. to be implemented using setjmp / longjmp which seems to be more robust. This seems related to this unresolved upstream bug: https://sourceware.org/bugzilla/show_bug.cgi?id=14266 Our problem case was extracted into the following example code that shows the bug: https://github.com/cagney/pthread-cancel If -fexceptions is specified on GLIBC based GNU/Linux systems, pthread_cleanup_push() et.al. are implemented using GLIBC's unwinder. Unfortunately, it seems to fail when unwinding from a custom built shared object (is the object built correctly?). Removing -fexceptions causes pthread_cleanup_push() et.al. to be implemented using setjmp / longjmp which seems to be more robust.