Description of problem:
strace -p <pid of a kernel thread>
does not give permission denied!
(strace is a security sensitive operation, someone needs to evaluate how serious
This is a simple check accidentally omitted when converting the ptrace entry
checks for the new utrace-based code. It only affects the kthread case (tasks
with no ->mm), and the uid and LSM checks are still performed so this can only
be done by root (and perhaps can't be done under selinux policy, don't know).
I don't think it rises to the level of a security concern.
I have a fix on its way.
I committed the fixed utrace patch to kernel/devel, it will be in davej's next
kernel build. I only wish this were a more interesting and auspicious bug to go
with the palindromic bug number.
This was fixed in the FC-6 release kernel.