net, ipx: convert ipx_route.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 <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Reshetova, Elena 2017-07-04 15:53:10 +03:00 committed by David S. Miller
parent d25189ca86
commit 16f73c9649
2 changed files with 4 additions and 4 deletions

View File

@ -81,7 +81,7 @@ struct ipx_route {
unsigned char ir_routed;
unsigned char ir_router_node[IPX_NODE_LEN];
struct list_head node; /* node in ipx_routes list */
atomic_t refcnt;
refcount_t refcnt;
};
struct ipx_cb {
@ -164,12 +164,12 @@ static __inline__ void ipxitf_put(struct ipx_interface *intrfc)
static __inline__ void ipxrtr_hold(struct ipx_route *rt)
{
atomic_inc(&rt->refcnt);
refcount_inc(&rt->refcnt);
}
static __inline__ void ipxrtr_put(struct ipx_route *rt)
{
if (atomic_dec_and_test(&rt->refcnt))
if (refcount_dec_and_test(&rt->refcnt))
kfree(rt);
}
#endif /* _NET_INET_IPX_H_ */

View File

@ -59,7 +59,7 @@ int ipxrtr_add_route(__be32 network, struct ipx_interface *intrfc,
if (!rt)
goto out;
atomic_set(&rt->refcnt, 1);
refcount_set(&rt->refcnt, 1);
ipxrtr_hold(rt);
write_lock_bh(&ipx_routes_lock);
list_add(&rt->node, &ipx_routes);