Commit ca3fde52 authored by Jann Horn's avatar Jann Horn Committed by John Johansen

apparmor: don't try to replace stale label in ptraceme check

begin_current_label_crit_section() must run in sleepable context because
when label_is_stale() is true, aa_replace_current_label() runs, which uses
prepare_creds(), which can sleep.

Until now, the ptraceme access check (which runs with tasklist_lock held)
violated this rule.

Fixes: b2d09ae4 ("apparmor: move ptrace checks to using labels")
Reported-by: default avatarCyrill Gorcunov <gorcunov@gmail.com>
Reported-by: default avatarkernel test robot <rong.a.chen@intel.com>
Signed-off-by: default avatarJann Horn <jannh@google.com>
Signed-off-by: default avatarJohn Johansen <john.johansen@canonical.com>
parent 0fb871cc
...@@ -132,11 +132,11 @@ static int apparmor_ptrace_traceme(struct task_struct *parent) ...@@ -132,11 +132,11 @@ static int apparmor_ptrace_traceme(struct task_struct *parent)
struct aa_label *tracer, *tracee; struct aa_label *tracer, *tracee;
int error; int error;
tracee = begin_current_label_crit_section(); tracee = __begin_current_label_crit_section();
tracer = aa_get_task_label(parent); tracer = aa_get_task_label(parent);
error = aa_may_ptrace(tracer, tracee, AA_PTRACE_TRACE); error = aa_may_ptrace(tracer, tracee, AA_PTRACE_TRACE);
aa_put_label(tracer); aa_put_label(tracer);
end_current_label_crit_section(tracee); __end_current_label_crit_section(tracee);
return error; return error;
} }
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment