From: Jann Horn jannh@google.com
[ Upstream commit ca3fde5214e1d24f78269b337d3f22afd6bf445e ]
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: b2d09ae449ced ("apparmor: move ptrace checks to using labels") Reported-by: Cyrill Gorcunov gorcunov@gmail.com Reported-by: kernel test robot rong.a.chen@intel.com Signed-off-by: Jann Horn jannh@google.com Signed-off-by: John Johansen john.johansen@canonical.com Signed-off-by: Sasha Levin sashal@kernel.org --- security/apparmor/lsm.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/security/apparmor/lsm.c b/security/apparmor/lsm.c index 4f08023101f3c..1c6b389ad8f94 100644 --- a/security/apparmor/lsm.c +++ b/security/apparmor/lsm.c @@ -123,11 +123,11 @@ static int apparmor_ptrace_traceme(struct task_struct *parent) struct aa_label *tracer, *tracee; int error;
- tracee = begin_current_label_crit_section(); + tracee = __begin_current_label_crit_section(); tracer = aa_get_task_label(parent); error = aa_may_ptrace(tracer, tracee, AA_PTRACE_TRACE); aa_put_label(tracer); - end_current_label_crit_section(tracee); + __end_current_label_crit_section(tracee);
return error; }