From 788936641ac8bc92c531f09b79bf44775fac1350 Mon Sep 17 00:00:00 2001 From: "Reshetova, Elena" Date: Tue, 4 Jul 2017 15:53:02 +0300 Subject: [PATCH] net, atm: convert lec_arp_table.usage 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 --- net/atm/lec.c | 6 +++--- net/atm/lec_arpc.h | 2 +- 2 files changed, 4 insertions(+), 4 deletions(-) diff --git a/net/atm/lec.c b/net/atm/lec.c index 7554571..093fe87 100644 --- a/net/atm/lec.c +++ b/net/atm/lec.c @@ -101,12 +101,12 @@ static void lec_vcc_close(struct lec_priv *priv, struct atm_vcc *vcc); /* must be done under lec_arp_lock */ static inline void lec_arp_hold(struct lec_arp_table *entry) { - atomic_inc(&entry->usage); + refcount_inc(&entry->usage); } static inline void lec_arp_put(struct lec_arp_table *entry) { - if (atomic_dec_and_test(&entry->usage)) + if (refcount_dec_and_test(&entry->usage)) kfree(entry); } @@ -1564,7 +1564,7 @@ static struct lec_arp_table *make_entry(struct lec_priv *priv, to_return->last_used = jiffies; to_return->priv = priv; skb_queue_head_init(&to_return->tx_wait); - atomic_set(&to_return->usage, 1); + refcount_set(&to_return->usage, 1); return to_return; } diff --git a/net/atm/lec_arpc.h b/net/atm/lec_arpc.h index ec67435..d923f53 100644 --- a/net/atm/lec_arpc.h +++ b/net/atm/lec_arpc.h @@ -47,7 +47,7 @@ struct lec_arp_table { * the length of the tlvs array */ struct sk_buff_head tx_wait; /* wait queue for outgoing packets */ - atomic_t usage; /* usage count */ + refcount_t usage; /* usage count */ }; /* -- 2.7.4