When finding a child profile via an rcu critical section, the profile may be put and scheduled for deletion after the child is found but before its refcount is incremented.
Protect against this by repeating the lookup if the profiles refcount is 0 and is one its way to deletion. Signed-off-by: John Johansen <[email protected]> --- security/apparmor/policy.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/security/apparmor/policy.c b/security/apparmor/policy.c index ca402d0..7807125 100644 --- a/security/apparmor/policy.c +++ b/security/apparmor/policy.c @@ -766,7 +766,9 @@ struct aa_profile *aa_find_child(struct aa_profile *parent, const char *name) struct aa_profile *profile; rcu_read_lock(); - profile = aa_get_profile(__find_child(&parent->base.profiles, name)); + do { + profile = __find_child(&parent->base.profiles, name); + } while (profile && !aa_get_profile_not0(profile)); rcu_read_unlock(); /* refcount released by caller */ -- 2.7.4 -- AppArmor mailing list [email protected] Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/apparmor
