From: Jann Horn Date: Sat, 29 Sep 2018 03:49:26 +0200 Subject: apparmor: don't try to replace stale label in ptraceme check Origin: https://git.kernel.org/linus/ca3fde5214e1d24f78269b337d3f22afd6bf445e Bug-Debian: https://bugs.debian.org/963493 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 Reported-by: kernel test robot Signed-off-by: Jann Horn Signed-off-by: John Johansen --- 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 2c842f24821b..d08aac05c65a 100644 --- a/security/apparmor/lsm.c +++ b/security/apparmor/lsm.c @@ -132,11 +132,11 @@ 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; } -- 2.27.0