net, netrom: convert nr_node.refcount 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 15:53:12 +03:00 committed by David S. Miller
parent af4207494d
commit 156be7edc8
2 changed files with 4 additions and 4 deletions

View file

@ -110,7 +110,7 @@ struct nr_node {
unsigned char which;
unsigned char count;
struct nr_route routes[3];
atomic_t refcount;
refcount_t refcount;
spinlock_t node_lock;
};
@ -119,11 +119,11 @@ struct nr_node {
*********************************************************************/
#define nr_node_hold(__nr_node) \
atomic_inc(&((__nr_node)->refcount))
refcount_inc(&((__nr_node)->refcount))
static __inline__ void nr_node_put(struct nr_node *nr_node)
{
if (atomic_dec_and_test(&nr_node->refcount)) {
if (refcount_dec_and_test(&nr_node->refcount)) {
kfree(nr_node);
}
}

View file

@ -184,7 +184,7 @@ static int __must_check nr_add_node(ax25_address *nr, const char *mnemonic,
nr_node->which = 0;
nr_node->count = 1;
atomic_set(&nr_node->refcount, 1);
refcount_set(&nr_node->refcount, 1);
spin_lock_init(&nr_node->node_lock);
nr_node->routes[0].quality = quality;