How to temporary change 'current' (task)

Vasiliy Kulikov
2011-06-17T08:37:00Z

Hi,

I wonder whether there is a simple way to temporary switch 'current' to
another task and then switch it back with minimum side effects? I need
it to call "reversed" ptrace_may_access() with swapped current and
target task. Introducing ptrace_task_may_access_me() would produce too
much noise in LSM (it also needs reversed security_ptrace_access_check()),
which is too loud for my needs.

Specifically, I need it to filter taskstats and proc connector requests
for a restriction of getting other processes' information:

http://permalink.gmane.org/gmane.linux.kernel/1155354

As the check is handled in the context of the ptrace target process,
ptrace_may_access() doesn't fit my needs.

Thanks,

--
Vasiliy