drivers, firewire: convert fw_node.ref_count 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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Elena Reshetova 2017-03-06 16:20:49 +02:00 committed by Greg Kroah-Hartman
parent f7d88d24c5
commit 392910cf3f
2 changed files with 5 additions and 5 deletions

View File

@ -124,7 +124,7 @@ static struct fw_node *fw_node_create(u32 sid, int port_count, int color)
node->initiated_reset = SELF_ID_PHY_INITIATOR(sid);
node->port_count = port_count;
atomic_set(&node->ref_count, 1);
refcount_set(&node->ref_count, 1);
INIT_LIST_HEAD(&node->link);
return node;

View File

@ -12,7 +12,7 @@
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/atomic.h>
#include <linux/refcount.h>
struct device;
struct fw_card;
@ -184,7 +184,7 @@ struct fw_node {
* local node to this node. */
u8 max_depth:4; /* Maximum depth to any leaf node */
u8 max_hops:4; /* Max hops in this sub tree */
atomic_t ref_count;
refcount_t ref_count;
/* For serializing node topology into a list. */
struct list_head link;
@ -197,14 +197,14 @@ struct fw_node {
static inline struct fw_node *fw_node_get(struct fw_node *node)
{
atomic_inc(&node->ref_count);
refcount_inc(&node->ref_count);
return node;
}
static inline void fw_node_put(struct fw_node *node)
{
if (atomic_dec_and_test(&node->ref_count))
if (refcount_dec_and_test(&node->ref_count))
kfree(node);
}