From 87078f26b6644c2ad8226cf29a7e3a6ef6c74ae2 Mon Sep 17 00:00:00 2001 From: "Reshetova, Elena" Date: Tue, 4 Jul 2017 09:35:00 +0300 Subject: net, ipv6: convert ip6addrlbl_entry.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 --- net/ipv6/addrlabel.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) (limited to 'net/ipv6') diff --git a/net/ipv6/addrlabel.c b/net/ipv6/addrlabel.c index 07cd7d248bb6..7a428f65c7ec 100644 --- a/net/ipv6/addrlabel.c +++ b/net/ipv6/addrlabel.c @@ -18,6 +18,7 @@ #include #include #include +#include #if 0 #define ADDRLABEL(x...) printk(x) @@ -36,7 +37,7 @@ struct ip6addrlbl_entry { int addrtype; u32 label; struct hlist_node list; - atomic_t refcnt; + refcount_t refcnt; struct rcu_head rcu; }; @@ -137,12 +138,12 @@ static void ip6addrlbl_free_rcu(struct rcu_head *h) static bool ip6addrlbl_hold(struct ip6addrlbl_entry *p) { - return atomic_inc_not_zero(&p->refcnt); + return refcount_inc_not_zero(&p->refcnt); } static inline void ip6addrlbl_put(struct ip6addrlbl_entry *p) { - if (atomic_dec_and_test(&p->refcnt)) + if (refcount_dec_and_test(&p->refcnt)) call_rcu(&p->rcu, ip6addrlbl_free_rcu); } @@ -236,7 +237,7 @@ static struct ip6addrlbl_entry *ip6addrlbl_alloc(struct net *net, newp->label = label; INIT_HLIST_NODE(&newp->list); write_pnet(&newp->lbl_net, net); - atomic_set(&newp->refcnt, 1); + refcount_set(&newp->refcnt, 1); return newp; } -- cgit