From 04fdc099f9c80c7775dbac388fc97e156d4d47e7 Mon Sep 17 00:00:00 2001 From: John Johansen <john.johansen@canonical.com> Date: Tue, 28 Jun 2011 15:06:38 +0100 Subject: [PATCH] AppArmor: Fix reference to rcu protected pointer outside of rcu_read_lock The pointer returned from tracehook_tracer_task() is only valid inside the rcu_read_lock. However the tracer pointer obtained is being passed to aa_may_ptrace outside of the rcu_read_lock critical section. Mover the aa_may_ptrace test into the rcu_read_lock critical section, to fix this. Kernels affected: 2.6.36 - 3.0 Reported-by: Oleg Nesterov <oleg@redhat.com> Cc: stable@kernel.org Signed-off-by: John Johansen <john.johansen@canonical.com> --- security/apparmor/domain.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/security/apparmor/domain.c b/security/apparmor/domain.c index c825c6e0b636e..78adc4303efa3 100644 --- a/security/apparmor/domain.c +++ b/security/apparmor/domain.c @@ -73,7 +73,6 @@ static int may_change_ptraced_domain(struct task_struct *task, cred = get_task_cred(tracer); tracerp = aa_cred_profile(cred); } - rcu_read_unlock(); /* not ptraced */ if (!tracer || unconfined(tracerp)) @@ -82,6 +81,7 @@ static int may_change_ptraced_domain(struct task_struct *task, error = aa_may_ptrace(tracer, tracerp, to_profile, PTRACE_MODE_ATTACH); out: + rcu_read_unlock(); if (cred) put_cred(cred); -- GitLab