refcount_t type and corresponding API should be used instead of atomic_t when the variable is used as a reference counter. This allows to avoid accidental refcounter overflows that might lead to use-after-free situations. Signed-off-by: Elena Reshetova <elena.reshetova@xxxxxxxxx> Signed-off-by: Hans Liljestrand <ishkamiel@xxxxxxxxx> Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx> Signed-off-by: David Windsor <dwindsor@xxxxxxxxx> --- drivers/net/macsec.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/net/macsec.c b/drivers/net/macsec.c index bc0b00a..1869223 100644 --- a/drivers/net/macsec.c +++ b/drivers/net/macsec.c @@ -172,7 +172,7 @@ struct macsec_rx_sc { bool active; struct macsec_rx_sa __rcu *sa[MACSEC_NUM_AN]; struct pcpu_rx_sc_stats __percpu *stats; - atomic_t refcnt; + refcount_t refcnt; struct rcu_head rcu_head; }; @@ -331,12 +331,12 @@ static void free_rx_sc_rcu(struct rcu_head *head) static struct macsec_rx_sc *macsec_rxsc_get(struct macsec_rx_sc *sc) { - return atomic_inc_not_zero(&sc->refcnt) ? sc : NULL; + return refcount_inc_not_zero(&sc->refcnt) ? sc : NULL; } static void macsec_rxsc_put(struct macsec_rx_sc *sc) { - if (atomic_dec_and_test(&sc->refcnt)) + if (refcount_dec_and_test(&sc->refcnt)) call_rcu(&sc->rcu_head, free_rx_sc_rcu); } @@ -1396,7 +1396,7 @@ static struct macsec_rx_sc *create_rx_sc(struct net_device *dev, sci_t sci) rx_sc->sci = sci; rx_sc->active = true; - atomic_set(&rx_sc->refcnt, 1); + refcount_set(&rx_sc->refcnt, 1); secy = &macsec_priv(dev)->secy; rcu_assign_pointer(rx_sc->next, secy->rx_sc); -- 2.7.4