[PATCH 04/17] net: convert sk_buff.users from atomic_t to refcount_t

From: Elena Reshetova
Date: Thu Mar 16 2017 - 11:35:01 EST

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@xxxxxxxxx>
Signed-off-by: Hans Liljestrand <ishkamiel@xxxxxxxxx>
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
Signed-off-by: David Windsor <dwindsor@xxxxxxxxx>
---
drivers/infiniband/hw/nes/nes_cm.c | 4 ++--
drivers/isdn/mISDN/socket.c | 2 +-
drivers/net/rionet.c | 2 +-
drivers/s390/net/ctcm_main.c | 26 +++++++++++++-------------
drivers/s390/net/netiucv.c | 10 +++++-----
drivers/s390/net/qeth_core_main.c | 4 ++--
drivers/scsi/cxgbi/libcxgbi.h | 2 +-
include/linux/skbuff.h | 6 +++---
net/core/datagram.c | 8 ++++----
net/core/dev.c | 10 +++++-----
net/core/netpoll.c | 4 ++--
net/core/pktgen.c | 16 ++++++++--------
net/core/rtnetlink.c | 2 +-
net/core/skbuff.c | 20 ++++++++++----------
net/dccp/ipv6.c | 2 +-
net/ipv6/syncookies.c | 2 +-
net/ipv6/tcp_ipv6.c | 2 +-
net/key/af_key.c | 4 ++--
net/netlink/af_netlink.c | 6 +++---
net/rxrpc/skbuff.c | 12 ++++++------
net/sctp/outqueue.c | 2 +-
net/sctp/socket.c | 2 +-
22 files changed, 74 insertions(+), 74 deletions(-)

diff --git a/drivers/infiniband/hw/nes/nes_cm.c b/drivers/infiniband/hw/nes/nes_cm.c
index fb983df..08dac2e 100644
--- a/drivers/infiniband/hw/nes/nes_cm.c
+++ b/drivers/infiniband/hw/nes/nes_cm.c
@@ -743,7 +743,7 @@ int schedule_nes_timer(struct nes_cm_node *cm_node, struct sk_buff *skb,

if (type == NES_TIMER_TYPE_SEND) {
new_send->seq_num = ntohl(tcp_hdr(skb)->seq);
- atomic_inc(&new_send->skb->users);
+ refcount_inc(&new_send->skb->users);
spin_lock_irqsave(&cm_node->retrans_list_lock, flags);
cm_node->send_entry = new_send;
add_ref_cm_node(cm_node);
@@ -925,7 +925,7 @@ static void nes_cm_timer_tick(unsigned long pass)
flags);
break;
}
- atomic_inc(&send_entry->skb->users);
+ refcount_inc(&send_entry->skb->users);
cm_packets_retrans++;
nes_debug(NES_DBG_CM, "Retransmitting send_entry %p "
"for node %p, jiffies = %lu, time to send = "
diff --git a/drivers/isdn/mISDN/socket.c b/drivers/isdn/mISDN/socket.c
index 99e5f97..c5603d1 100644
--- a/drivers/isdn/mISDN/socket.c
+++ b/drivers/isdn/mISDN/socket.c
@@ -155,7 +155,7 @@ mISDN_sock_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
copied = skb->len + MISDN_HEADER_LEN;
if (len < copied) {
if (flags & MSG_PEEK)
- atomic_dec(&skb->users);
+ refcount_dec(&skb->users);
else
skb_queue_head(&sk->sk_receive_queue, skb);
return -ENOSPC;
diff --git a/drivers/net/rionet.c b/drivers/net/rionet.c
index 300bb14..e9f101c 100644
--- a/drivers/net/rionet.c
+++ b/drivers/net/rionet.c
@@ -201,7 +201,7 @@ static int rionet_start_xmit(struct sk_buff *skb, struct net_device *ndev)
rionet_queue_tx_msg(skb, ndev,
nets[rnet->mport->id].active[i]);
if (count)
- atomic_inc(&skb->users);
+ refcount_inc(&skb->users);
count++;
}
} else if (RIONET_MAC_MATCH(eth->h_dest)) {
diff --git a/drivers/s390/net/ctcm_main.c b/drivers/s390/net/ctcm_main.c
index ac65f12..d079d02 100644
--- a/drivers/s390/net/ctcm_main.c
+++ b/drivers/s390/net/ctcm_main.c
@@ -483,7 +483,7 @@ static int ctcm_transmit_skb(struct channel *ch, struct sk_buff *skb)
spin_unlock_irqrestore(&ch->collect_lock, saveflags);
return -EBUSY;
} else {
- atomic_inc(&skb->users);
+ refcount_inc(&skb->users);
header.length = l;
header.type = skb->protocol;
header.unused = 0;
@@ -500,7 +500,7 @@ static int ctcm_transmit_skb(struct channel *ch, struct sk_buff *skb)
* Protect skb against beeing free'd by upper
* layers.
*/
- atomic_inc(&skb->users);
+ refcount_inc(&skb->users);
ch->prof.txlen += skb->len;
header.length = skb->len + LL_HEADER_LENGTH;
header.type = skb->protocol;
@@ -517,14 +517,14 @@ static int ctcm_transmit_skb(struct channel *ch, struct sk_buff *skb)
if (hi) {
nskb = alloc_skb(skb->len, GFP_ATOMIC | GFP_DMA);
if (!nskb) {
- atomic_dec(&skb->users);
+ refcount_dec(&skb->users);
skb_pull(skb, LL_HEADER_LENGTH + 2);
ctcm_clear_busy(ch->netdev);
return -ENOMEM;
} else {
memcpy(skb_put(nskb, skb->len), skb->data, skb->len);
- atomic_inc(&nskb->users);
- atomic_dec(&skb->users);
+ refcount_inc(&nskb->users);
+ refcount_dec(&skb->users);
dev_kfree_skb_irq(skb);
skb = nskb;
}
@@ -542,7 +542,7 @@ static int ctcm_transmit_skb(struct channel *ch, struct sk_buff *skb)
* Remove our header. It gets added
* again on retransmit.
*/
- atomic_dec(&skb->users);
+ refcount_dec(&skb->users);
skb_pull(skb, LL_HEADER_LENGTH + 2);
ctcm_clear_busy(ch->netdev);
return -ENOMEM;
@@ -553,7 +553,7 @@ static int ctcm_transmit_skb(struct channel *ch, struct sk_buff *skb)
ch->ccw[1].count = skb->len;
skb_copy_from_linear_data(skb,
skb_put(ch->trans_skb, skb->len), skb->len);
- atomic_dec(&skb->users);
+ refcount_dec(&skb->users);
dev_kfree_skb_irq(skb);
ccw_idx = 0;
} else {
@@ -679,7 +679,7 @@ static int ctcmpc_transmit_skb(struct channel *ch, struct sk_buff *skb)

if ((fsm_getstate(ch->fsm) != CTC_STATE_TXIDLE) || grp->in_sweep) {
spin_lock_irqsave(&ch->collect_lock, saveflags);
- atomic_inc(&skb->users);
+ refcount_inc(&skb->users);
p_header = kmalloc(PDU_HEADER_LENGTH, gfp_type());

if (!p_header) {
@@ -716,7 +716,7 @@ static int ctcmpc_transmit_skb(struct channel *ch, struct sk_buff *skb)
* Protect skb against beeing free'd by upper
* layers.
*/
- atomic_inc(&skb->users);
+ refcount_inc(&skb->users);

/*
* IDAL support in CTCM is broken, so we have to
@@ -729,8 +729,8 @@ static int ctcmpc_transmit_skb(struct channel *ch, struct sk_buff *skb)
goto nomem_exit;
} else {
memcpy(skb_put(nskb, skb->len), skb->data, skb->len);
- atomic_inc(&nskb->users);
- atomic_dec(&skb->users);
+ refcount_inc(&nskb->users);
+ refcount_dec(&skb->users);
dev_kfree_skb_irq(skb);
skb = nskb;
}
@@ -810,7 +810,7 @@ static int ctcmpc_transmit_skb(struct channel *ch, struct sk_buff *skb)
ch->trans_skb->len = 0;
ch->ccw[1].count = skb->len;
memcpy(skb_put(ch->trans_skb, skb->len), skb->data, skb->len);
- atomic_dec(&skb->users);
+ refcount_dec(&skb->users);
dev_kfree_skb_irq(skb);
ccw_idx = 0;
CTCM_PR_DBGDATA("%s(%s): trans_skb len: %04x\n"
@@ -855,7 +855,7 @@ static int ctcmpc_transmit_skb(struct channel *ch, struct sk_buff *skb)
"%s(%s): MEMORY allocation ERROR\n",
CTCM_FUNTAIL, ch->id);
rc = -ENOMEM;
- atomic_dec(&skb->users);
+ refcount_dec(&skb->users);
dev_kfree_skb_any(skb);
fsm_event(priv->mpcg->fsm, MPCG_EVENT_INOP, dev);
done:
diff --git a/drivers/s390/net/netiucv.c b/drivers/s390/net/netiucv.c
index 3f85b97..44fd71c 100644
--- a/drivers/s390/net/netiucv.c
+++ b/drivers/s390/net/netiucv.c
@@ -743,7 +743,7 @@ static void conn_action_txdone(fsm_instance *fi, int event, void *arg)
conn->prof.tx_pending--;
if (single_flag) {
if ((skb = skb_dequeue(&conn->commit_queue))) {
- atomic_dec(&skb->users);
+ refcount_dec(&skb->users);
if (privptr) {
privptr->stats.tx_packets++;
privptr->stats.tx_bytes +=
@@ -767,7 +767,7 @@ static void conn_action_txdone(fsm_instance *fi, int event, void *arg)
txbytes += skb->len;
txpackets++;
stat_maxcq++;
- atomic_dec(&skb->users);
+ refcount_dec(&skb->users);
dev_kfree_skb_any(skb);
}
if (conn->collect_len > conn->prof.maxmulti)
@@ -959,7 +959,7 @@ static void netiucv_purge_skb_queue(struct sk_buff_head *q)
struct sk_buff *skb;

while ((skb = skb_dequeue(q))) {
- atomic_dec(&skb->users);
+ refcount_dec(&skb->users);
dev_kfree_skb_any(skb);
}
}
@@ -1177,7 +1177,7 @@ static int netiucv_transmit_skb(struct iucv_connection *conn,
IUCV_DBF_TEXT(data, 2,
"EBUSY from netiucv_transmit_skb\n");
} else {
- atomic_inc(&skb->users);
+ refcount_inc(&skb->users);
skb_queue_tail(&conn->collect_queue, skb);
conn->collect_len += l;
rc = 0;
@@ -1247,7 +1247,7 @@ static int netiucv_transmit_skb(struct iucv_connection *conn,
} else {
if (copied)
dev_kfree_skb(skb);
- atomic_inc(&nskb->users);
+ refcount_inc(&nskb->users);
skb_queue_tail(&conn->commit_queue, nskb);
}
}
diff --git a/drivers/s390/net/qeth_core_main.c b/drivers/s390/net/qeth_core_main.c
index 315d8a2..5103a02 100644
--- a/drivers/s390/net/qeth_core_main.c
+++ b/drivers/s390/net/qeth_core_main.c
@@ -1239,7 +1239,7 @@ static void qeth_release_skbs(struct qeth_qdio_out_buffer *buf)
iucv->sk_txnotify(skb, TX_NOTIFY_GENERALERROR);
}
}
- atomic_dec(&skb->users);
+ refcount_dec(&skb->users);
dev_kfree_skb_any(skb);
skb = skb_dequeue(&buf->skb_list);
}
@@ -3969,7 +3969,7 @@ static inline int qeth_fill_buffer(struct qeth_qdio_out_q *queue,
int flush_cnt = 0, hdr_len, large_send = 0;

buffer = buf->buffer;
- atomic_inc(&skb->users);
+ refcount_inc(&skb->users);
skb_queue_tail(&buf->skb_list, skb);

/*check first on TSO ....*/
diff --git a/drivers/scsi/cxgbi/libcxgbi.h b/drivers/scsi/cxgbi/libcxgbi.h
index 18e0ea8..9584b062 100644
--- a/drivers/scsi/cxgbi/libcxgbi.h
+++ b/drivers/scsi/cxgbi/libcxgbi.h
@@ -378,7 +378,7 @@ static inline void cxgbi_sock_enqueue_wr(struct cxgbi_sock *csk,
* just one user currently so we use atomic_set rather than skb_get
* to avoid the atomic op.
*/
- atomic_set(&skb->users, 2);
+ refcount_set(&skb->users, 2);

if (!csk->wr_pending_head)
csk->wr_pending_head = skb;
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 957a2b0..0bcaec4 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -815,7 +815,7 @@ struct sk_buff {
unsigned char *head,
*data;
unsigned int truesize;
- atomic_t users;
+ refcount_t users;
};

#ifdef __KERNEL__
@@ -1313,7 +1313,7 @@ static inline struct sk_buff *skb_queue_prev(const struct sk_buff_head *list,
*/
static inline struct sk_buff *skb_get(struct sk_buff *skb)
{
- atomic_inc(&skb->users);
+ refcount_inc(&skb->users);
return skb;
}

@@ -1414,7 +1414,7 @@ static inline void __skb_header_release(struct sk_buff *skb)
*/
static inline int skb_shared(const struct sk_buff *skb)
{
- return atomic_read(&skb->users) != 1;
+ return refcount_read(&skb->users) != 1;
}

/**
diff --git a/net/core/datagram.c b/net/core/datagram.c
index ea63334..281e5d6 100644
--- a/net/core/datagram.c
+++ b/net/core/datagram.c
@@ -244,7 +244,7 @@ struct sk_buff *__skb_try_recv_datagram(struct sock *sk, unsigned int flags,
}
}
*peeked = 1;
- atomic_inc(&skb->users);
+ refcount_inc(&skb->users);
} else {
__skb_unlink(skb, queue);
if (destructor)
@@ -313,9 +313,9 @@ void __skb_free_datagram_locked(struct sock *sk, struct sk_buff *skb, int len)
{
bool slow;

- if (likely(atomic_read(&skb->users) == 1))
+ if (likely(refcount_read(&skb->users) == 1))
smp_rmb();
- else if (likely(!atomic_dec_and_test(&skb->users))) {
+ else if (likely(!refcount_dec_and_test(&skb->users))) {
sk_peek_offset_bwd(sk, len);
return;
}
@@ -343,7 +343,7 @@ int __sk_queue_drop_skb(struct sock *sk, struct sk_buff *skb,
spin_lock_bh(&sk->sk_receive_queue.lock);
if (skb == skb_peek(&sk->sk_receive_queue)) {
__skb_unlink(skb, &sk->sk_receive_queue);
- atomic_dec(&skb->users);
+ refcount_dec(&skb->users);
if (destructor)
destructor(sk, skb);
err = 0;
diff --git a/net/core/dev.c b/net/core/dev.c
index d947308..eeb6338 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -1830,7 +1830,7 @@ static inline int deliver_skb(struct sk_buff *skb,
{
if (unlikely(skb_orphan_frags(skb, GFP_ATOMIC)))
return -ENOMEM;
- atomic_inc(&skb->users);
+ refcount_inc(&skb->users);
return pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
}

@@ -2449,10 +2449,10 @@ void __dev_kfree_skb_irq(struct sk_buff *skb, enum skb_free_reason reason)
{
unsigned long flags;

- if (likely(atomic_read(&skb->users) == 1)) {
+ if (likely(refcount_read(&skb->users) == 1)) {
smp_rmb();
- atomic_set(&skb->users, 0);
- } else if (likely(!atomic_dec_and_test(&skb->users))) {
+ refcount_set(&skb->users, 0);
+ } else if (likely(!refcount_dec_and_test(&skb->users))) {
return;
}
get_kfree_skb_cb(skb)->reason = reason;
@@ -3864,7 +3864,7 @@ static __latent_entropy void net_tx_action(struct softirq_action *h)

clist = clist->next;

- WARN_ON(atomic_read(&skb->users));
+ WARN_ON(refcount_read(&skb->users));
if (likely(get_kfree_skb_cb(skb)->reason == SKB_REASON_CONSUMED))
trace_consume_skb(skb);
else
diff --git a/net/core/netpoll.c b/net/core/netpoll.c
index 9424673..891d88e 100644
--- a/net/core/netpoll.c
+++ b/net/core/netpoll.c
@@ -271,7 +271,7 @@ static void zap_completion_queue(void)
struct sk_buff *skb = clist;
clist = clist->next;
if (!skb_irq_freeable(skb)) {
- atomic_inc(&skb->users);
+ refcount_inc(&skb->users);
dev_kfree_skb_any(skb); /* put this one back */
} else {
__kfree_skb(skb);
@@ -303,7 +303,7 @@ static struct sk_buff *find_skb(struct netpoll *np, int len, int reserve)
return NULL;
}

- atomic_set(&skb->users, 1);
+ refcount_set(&skb->users, 1);
skb_reserve(skb, reserve);
return skb;
}
diff --git a/net/core/pktgen.c b/net/core/pktgen.c
index 96947f5..598355f 100644
--- a/net/core/pktgen.c
+++ b/net/core/pktgen.c
@@ -3361,7 +3361,7 @@ static void pktgen_wait_for_skb(struct pktgen_dev *pkt_dev)
{
ktime_t idle_start = ktime_get();

- while (atomic_read(&(pkt_dev->skb->users)) != 1) {
+ while (refcount_read(&(pkt_dev->skb->users)) != 1) {
if (signal_pending(current))
break;

@@ -3418,7 +3418,7 @@ static void pktgen_xmit(struct pktgen_dev *pkt_dev)
if (pkt_dev->xmit_mode == M_NETIF_RECEIVE) {
skb = pkt_dev->skb;
skb->protocol = eth_type_trans(skb, skb->dev);
- atomic_add(burst, &skb->users);
+ refcount_add(burst, &skb->users);
local_bh_disable();
do {
ret = netif_receive_skb(skb);
@@ -3426,11 +3426,11 @@ static void pktgen_xmit(struct pktgen_dev *pkt_dev)
pkt_dev->errors++;
pkt_dev->sofar++;
pkt_dev->seq_num++;
- if (atomic_read(&skb->users) != burst) {
+ if (refcount_read(&skb->users) != burst) {
/* skb was queued by rps/rfs or taps,
* so cannot reuse this skb
*/
- atomic_sub(burst - 1, &skb->users);
+ WARN_ON(refcount_sub_and_test(burst - 1, &skb->users));
/* get out of the loop and wait
* until skb is consumed
*/
@@ -3444,7 +3444,7 @@ static void pktgen_xmit(struct pktgen_dev *pkt_dev)
goto out; /* Skips xmit_mode M_START_XMIT */
} else if (pkt_dev->xmit_mode == M_QUEUE_XMIT) {
local_bh_disable();
- atomic_inc(&pkt_dev->skb->users);
+ refcount_inc(&pkt_dev->skb->users);

ret = dev_queue_xmit(pkt_dev->skb);
switch (ret) {
@@ -3485,7 +3485,7 @@ static void pktgen_xmit(struct pktgen_dev *pkt_dev)
pkt_dev->last_ok = 0;
goto unlock;
}
- atomic_add(burst, &pkt_dev->skb->users);
+ refcount_add(burst, &pkt_dev->skb->users);

xmit_more:
ret = netdev_start_xmit(pkt_dev->skb, odev, txq, --burst > 0);
@@ -3511,11 +3511,11 @@ static void pktgen_xmit(struct pktgen_dev *pkt_dev)
/* fallthru */
case NETDEV_TX_BUSY:
/* Retry it next time */
- atomic_dec(&(pkt_dev->skb->users));
+ refcount_dec(&(pkt_dev->skb->users));
pkt_dev->last_ok = 0;
}
if (unlikely(burst))
- atomic_sub(burst, &pkt_dev->skb->users);
+ WARN_ON(refcount_sub_and_test(burst, &pkt_dev->skb->users));
unlock:
HARD_TX_UNLOCK(odev, txq);

diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index c4e84c5..8044cf3 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -647,7 +647,7 @@ int rtnetlink_send(struct sk_buff *skb, struct net *net, u32 pid, unsigned int g

NETLINK_CB(skb).dst_group = group;
if (echo)
- atomic_inc(&skb->users);
+ refcount_inc(&skb->users);
netlink_broadcast(rtnl, skb, pid, group, GFP_KERNEL);
if (echo)
err = netlink_unicast(rtnl, skb, pid, MSG_DONTWAIT);
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 89f0d4e..94e961f 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -176,7 +176,7 @@ struct sk_buff *__alloc_skb_head(gfp_t gfp_mask, int node)
memset(skb, 0, offsetof(struct sk_buff, tail));
skb->head = NULL;
skb->truesize = sizeof(struct sk_buff);
- atomic_set(&skb->users, 1);
+ refcount_set(&skb->users, 1);

skb->mac_header = (typeof(skb->mac_header))~0U;
out:
@@ -247,7 +247,7 @@ struct sk_buff *__alloc_skb(unsigned int size, gfp_t gfp_mask,
/* Account for allocated memory : skb + skb->head */
skb->truesize = SKB_TRUESIZE(size);
skb->pfmemalloc = pfmemalloc;
- atomic_set(&skb->users, 1);
+ refcount_set(&skb->users, 1);
skb->head = data;
skb->data = data;
skb_reset_tail_pointer(skb);
@@ -314,7 +314,7 @@ struct sk_buff *__build_skb(void *data, unsigned int frag_size)

memset(skb, 0, offsetof(struct sk_buff, tail));
skb->truesize = SKB_TRUESIZE(size);
- atomic_set(&skb->users, 1);
+ refcount_set(&skb->users, 1);
skb->head = data;
skb->data = data;
skb_reset_tail_pointer(skb);
@@ -696,9 +696,9 @@ void kfree_skb(struct sk_buff *skb)
{
if (unlikely(!skb))
return;
- if (likely(atomic_read(&skb->users) == 1))
+ if (likely(refcount_read(&skb->users) == 1))
smp_rmb();
- else if (likely(!atomic_dec_and_test(&skb->users)))
+ else if (likely(!refcount_dec_and_test(&skb->users)))
return;
trace_kfree_skb(skb, __builtin_return_address(0));
__kfree_skb(skb);
@@ -748,9 +748,9 @@ void consume_skb(struct sk_buff *skb)
{
if (unlikely(!skb))
return;
- if (likely(atomic_read(&skb->users) == 1))
+ if (likely(refcount_read(&skb->users) == 1))
smp_rmb();
- else if (likely(!atomic_dec_and_test(&skb->users)))
+ else if (likely(!refcount_dec_and_test(&skb->users)))
return;
trace_consume_skb(skb);
__kfree_skb(skb);
@@ -807,9 +807,9 @@ void napi_consume_skb(struct sk_buff *skb, int budget)
return;
}

- if (likely(atomic_read(&skb->users) == 1))
+ if (likely(refcount_read(&skb->users) == 1))
smp_rmb();
- else if (likely(!atomic_dec_and_test(&skb->users)))
+ else if (likely(!refcount_dec_and_test(&skb->users)))
return;
/* if reaching here SKB is ready to free */
trace_consume_skb(skb);
@@ -906,7 +906,7 @@ static struct sk_buff *__skb_clone(struct sk_buff *n, struct sk_buff *skb)
C(head_frag);
C(data);
C(truesize);
- atomic_set(&n->users, 1);
+ refcount_set(&n->users, 1);

atomic_inc(&(skb_shinfo(skb)->dataref));
skb->cloned = 1;
diff --git a/net/dccp/ipv6.c b/net/dccp/ipv6.c
index b4019a5..c734eea 100644
--- a/net/dccp/ipv6.c
+++ b/net/dccp/ipv6.c
@@ -351,7 +351,7 @@ static int dccp_v6_conn_request(struct sock *sk, struct sk_buff *skb)
if (ipv6_opt_accepted(sk, skb, IP6CB(skb)) ||
np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo ||
np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim) {
- atomic_inc(&skb->users);
+ refcount_inc(&skb->users);
ireq->pktopts = skb;
}
ireq->ir_iif = sk->sk_bound_dev_if;
diff --git a/net/ipv6/syncookies.c b/net/ipv6/syncookies.c
index 895ff65..2626a1d 100644
--- a/net/ipv6/syncookies.c
+++ b/net/ipv6/syncookies.c
@@ -185,7 +185,7 @@ struct sock *cookie_v6_check(struct sock *sk, struct sk_buff *skb)
if (ipv6_opt_accepted(sk, skb, &TCP_SKB_CB(skb)->header.h6) ||
np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo ||
np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim) {
- atomic_inc(&skb->users);
+ refcount_inc(&skb->users);
ireq->pktopts = skb;
}

diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index bdbc432..21bb2fc 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -718,7 +718,7 @@ static void tcp_v6_init_req(struct request_sock *req,
np->rxopt.bits.rxinfo ||
np->rxopt.bits.rxoinfo || np->rxopt.bits.rxhlim ||
np->rxopt.bits.rxohlim || np->repflow)) {
- atomic_inc(&skb->users);
+ refcount_inc(&skb->users);
ireq->pktopts = skb;
}
}
diff --git a/net/key/af_key.c b/net/key/af_key.c
index c6252ed..9d96b82 100644
--- a/net/key/af_key.c
+++ b/net/key/af_key.c
@@ -194,11 +194,11 @@ static int pfkey_broadcast_one(struct sk_buff *skb, struct sk_buff **skb2,

sock_hold(sk);
if (*skb2 == NULL) {
- if (atomic_read(&skb->users) != 1) {
+ if (refcount_read(&skb->users) != 1) {
*skb2 = skb_clone(skb, allocation);
} else {
*skb2 = skb;
- atomic_inc(&skb->users);
+ refcount_inc(&skb->users);
}
}
if (*skb2 != NULL) {
diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c
index 7b73c7c..7dac4a9 100644
--- a/net/netlink/af_netlink.c
+++ b/net/netlink/af_netlink.c
@@ -1797,7 +1797,7 @@ static int netlink_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
}

if (dst_group) {
- atomic_inc(&skb->users);
+ refcount_inc(&skb->users);
netlink_broadcast(sk, skb, dst_portid, dst_group, GFP_KERNEL);
}
err = netlink_unicast(sk, skb, dst_portid, msg->msg_flags&MSG_DONTWAIT);
@@ -2175,7 +2175,7 @@ int __netlink_dump_start(struct sock *ssk, struct sk_buff *skb,
struct netlink_sock *nlk;
int ret;

- atomic_inc(&skb->users);
+ refcount_inc(&skb->users);

sk = netlink_lookup(sock_net(ssk), ssk->sk_protocol, NETLINK_CB(skb).portid);
if (sk == NULL) {
@@ -2332,7 +2332,7 @@ int nlmsg_notify(struct sock *sk, struct sk_buff *skb, u32 portid,
int exclude_portid = 0;

if (report) {
- atomic_inc(&skb->users);
+ refcount_inc(&skb->users);
exclude_portid = portid;
}

diff --git a/net/rxrpc/skbuff.c b/net/rxrpc/skbuff.c
index 67b02c4..b8985d0 100644
--- a/net/rxrpc/skbuff.c
+++ b/net/rxrpc/skbuff.c
@@ -27,7 +27,7 @@ void rxrpc_new_skb(struct sk_buff *skb, enum rxrpc_skb_trace op)
{
const void *here = __builtin_return_address(0);
int n = atomic_inc_return(select_skb_count(op));
- trace_rxrpc_skb(skb, op, atomic_read(&skb->users), n, here);
+ trace_rxrpc_skb(skb, op, refcount_read(&skb->users), n, here);
}

/*
@@ -38,7 +38,7 @@ void rxrpc_see_skb(struct sk_buff *skb, enum rxrpc_skb_trace op)
const void *here = __builtin_return_address(0);
if (skb) {
int n = atomic_read(select_skb_count(op));
- trace_rxrpc_skb(skb, op, atomic_read(&skb->users), n, here);
+ trace_rxrpc_skb(skb, op, refcount_read(&skb->users), n, here);
}
}

@@ -49,7 +49,7 @@ void rxrpc_get_skb(struct sk_buff *skb, enum rxrpc_skb_trace op)
{
const void *here = __builtin_return_address(0);
int n = atomic_inc_return(select_skb_count(op));
- trace_rxrpc_skb(skb, op, atomic_read(&skb->users), n, here);
+ trace_rxrpc_skb(skb, op, refcount_read(&skb->users), n, here);
skb_get(skb);
}

@@ -63,7 +63,7 @@ void rxrpc_free_skb(struct sk_buff *skb, enum rxrpc_skb_trace op)
int n;
CHECK_SLAB_OKAY(&skb->users);
n = atomic_dec_return(select_skb_count(op));
- trace_rxrpc_skb(skb, op, atomic_read(&skb->users), n, here);
+ trace_rxrpc_skb(skb, op, refcount_read(&skb->users), n, here);
kfree_skb(skb);
}
}
@@ -78,7 +78,7 @@ void rxrpc_lose_skb(struct sk_buff *skb, enum rxrpc_skb_trace op)
int n;
CHECK_SLAB_OKAY(&skb->users);
n = atomic_dec_return(select_skb_count(op));
- trace_rxrpc_skb(skb, op, atomic_read(&skb->users), n, here);
+ trace_rxrpc_skb(skb, op, refcount_read(&skb->users), n, here);
kfree_skb(skb);
}
}
@@ -93,7 +93,7 @@ void rxrpc_purge_queue(struct sk_buff_head *list)
while ((skb = skb_dequeue((list))) != NULL) {
int n = atomic_dec_return(select_skb_count(rxrpc_skb_rx_purged));
trace_rxrpc_skb(skb, rxrpc_skb_rx_purged,
- atomic_read(&skb->users), n, here);
+ refcount_read(&skb->users), n, here);
kfree_skb(skb);
}
}
diff --git a/net/sctp/outqueue.c b/net/sctp/outqueue.c
index db352e5..1d6dae9 100644
--- a/net/sctp/outqueue.c
+++ b/net/sctp/outqueue.c
@@ -1094,7 +1094,7 @@ static void sctp_outq_flush(struct sctp_outq *q, int rtx_timeout, gfp_t gfp)
sctp_cname(SCTP_ST_CHUNK(chunk->chunk_hdr->type)) :
"illegal chunk", ntohl(chunk->subh.data_hdr->tsn),
chunk->skb ? chunk->skb->head : NULL, chunk->skb ?
- atomic_read(&chunk->skb->users) : -1);
+ refcount_read(&chunk->skb->users) : -1);

/* Add the chunk to the packet. */
status = sctp_packet_transmit_chunk(packet, chunk, 0, gfp);
diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index 6f0a9be..c1120d5 100644
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -7421,7 +7421,7 @@ struct sk_buff *sctp_skb_recv_datagram(struct sock *sk, int flags,
if (flags & MSG_PEEK) {
skb = skb_peek(&sk->sk_receive_queue);
if (skb)
- atomic_inc(&skb->users);
+ refcount_inc(&skb->users);
} else {
skb = __skb_dequeue(&sk->sk_receive_queue);
}
--
2.7.4