From: Reshetova, Elena Date: Tue, 4 Jul 2017 06:34:58 +0000 (+0300) Subject: net, ipv6: convert ifacaddr6.aca_refcnt from atomic_t to refcount_t X-Git-Tag: MMI-PSA29.97-13-9~5285^2~13^2~4 X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=affa78bc6a204fac1b5ced4f34376f53c70ec0ac;p=GitHub%2FMotorolaMobilityLLC%2Fkernel-slsi.git net, ipv6: convert ifacaddr6.aca_refcnt from atomic_t to refcount_t 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 Signed-off-by: Hans Liljestrand Signed-off-by: Kees Cook Signed-off-by: David Windsor Signed-off-by: David S. Miller --- diff --git a/include/net/if_inet6.h b/include/net/if_inet6.h index 4bb52ce634e8..d4088d1a688d 100644 --- a/include/net/if_inet6.h +++ b/include/net/if_inet6.h @@ -147,7 +147,7 @@ struct ifacaddr6 { struct rt6_info *aca_rt; struct ifacaddr6 *aca_next; int aca_users; - atomic_t aca_refcnt; + refcount_t aca_refcnt; unsigned long aca_cstamp; unsigned long aca_tstamp; }; diff --git a/net/ipv6/anycast.c b/net/ipv6/anycast.c index 514ac259f543..0bbab8a4b5d8 100644 --- a/net/ipv6/anycast.c +++ b/net/ipv6/anycast.c @@ -203,12 +203,12 @@ void ipv6_sock_ac_close(struct sock *sk) static void aca_get(struct ifacaddr6 *aca) { - atomic_inc(&aca->aca_refcnt); + refcount_inc(&aca->aca_refcnt); } static void aca_put(struct ifacaddr6 *ac) { - if (atomic_dec_and_test(&ac->aca_refcnt)) { + if (refcount_dec_and_test(&ac->aca_refcnt)) { in6_dev_put(ac->aca_idev); dst_release(&ac->aca_rt->dst); kfree(ac); @@ -232,7 +232,7 @@ static struct ifacaddr6 *aca_alloc(struct rt6_info *rt, aca->aca_users = 1; /* aca_tstamp should be updated upon changes */ aca->aca_cstamp = aca->aca_tstamp = jiffies; - atomic_set(&aca->aca_refcnt, 1); + refcount_set(&aca->aca_refcnt, 1); return aca; }