net, ipx: convert ipx_interface.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 15:53:09 +03:00 committed by David S. Miller
parent 0408c58be5
commit d25189ca86
3 changed files with 8 additions and 7 deletions

View File

@ -14,6 +14,7 @@
#include <linux/ipx.h>
#include <linux/list.h>
#include <linux/slab.h>
#include <linux/refcount.h>
struct ipx_address {
__be32 net;
@ -54,7 +55,7 @@ struct ipx_interface {
/* IPX address */
__be32 if_netnum;
unsigned char if_node[IPX_NODE_LEN];
atomic_t refcnt;
refcount_t refcnt;
/* physical device info */
struct net_device *if_dev;
@ -139,7 +140,7 @@ const char *ipx_device_name(struct ipx_interface *intrfc);
static __inline__ void ipxitf_hold(struct ipx_interface *intrfc)
{
atomic_inc(&intrfc->refcnt);
refcount_inc(&intrfc->refcnt);
}
void ipxitf_down(struct ipx_interface *intrfc);
@ -157,7 +158,7 @@ int ipxrtr_ioctl(unsigned int cmd, void __user *arg);
static __inline__ void ipxitf_put(struct ipx_interface *intrfc)
{
if (atomic_dec_and_test(&intrfc->refcnt))
if (refcount_dec_and_test(&intrfc->refcnt))
ipxitf_down(intrfc);
}

View File

@ -308,7 +308,7 @@ void ipxitf_down(struct ipx_interface *intrfc)
static void __ipxitf_put(struct ipx_interface *intrfc)
{
if (atomic_dec_and_test(&intrfc->refcnt))
if (refcount_dec_and_test(&intrfc->refcnt))
__ipxitf_down(intrfc);
}
@ -876,7 +876,7 @@ static struct ipx_interface *ipxitf_alloc(struct net_device *dev, __be32 netnum,
intrfc->if_ipx_offset = ipx_offset;
intrfc->if_sknum = IPX_MIN_EPHEMERAL_SOCKET;
INIT_HLIST_HEAD(&intrfc->if_sklist);
atomic_set(&intrfc->refcnt, 1);
refcount_set(&intrfc->refcnt, 1);
spin_lock_init(&intrfc->if_sklist_lock);
}
@ -1105,7 +1105,7 @@ static struct ipx_interface *ipxitf_auto_create(struct net_device *dev,
memcpy((char *)&(intrfc->if_node[IPX_NODE_LEN-dev->addr_len]),
dev->dev_addr, dev->addr_len);
spin_lock_init(&intrfc->if_sklist_lock);
atomic_set(&intrfc->refcnt, 1);
refcount_set(&intrfc->refcnt, 1);
ipxitf_insert(intrfc);
dev_hold(dev);
}

View File

@ -53,7 +53,7 @@ static int ipx_seq_interface_show(struct seq_file *seq, void *v)
seq_printf(seq, "%-11s", ipx_device_name(i));
seq_printf(seq, "%-9s", ipx_frame_name(i->if_dlink_type));
#ifdef IPX_REFCNT_DEBUG
seq_printf(seq, "%6d", atomic_read(&i->refcnt));
seq_printf(seq, "%6d", refcount_read(&i->refcnt));
#endif
seq_puts(seq, "\n");
out: