UBUNTU: SAUCE: AppArmor: Fix oops there is no tracer and doing unsafe transition.
As tracer is NULL in the exist case, ca_get_task_policy() has
not been called, so a direct exit looks ok.
John Johansen wrote:
> BugLink: http://bugs.launchpad.net/bugs/480112
> SRU Justification: This bug can cause confined process to oops at address 0.
> This can occur when executing a process if the LSM_UNSAFE_PTRACE |
> LSM_UNSAFE_PTRACE_CAP flags are set. The likely hood of if/how often this
> will occur depends on if ptrace is being used.
> As reported by Tetsuo Handa on kernel-team mailing list:
> In aa_may_change_ptraced_domain, if (!tracer) cred == NULL, and
> put_cred(cred) will oops. This will only happen on exec if the task
> is marked as LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP, so should
> only happen to ptraced tasks that are confined.
> Fix this by returning directly from aa_may_change_ptrace_domain if
> there is now tracer.
> Signed-off-by: John Johansen <firstname.lastname@example.org>
Acked-by: Stefan Bader <email@example.com>