kevin/linux
1
Fork 0
Code

net/packet: convert po->tp_loss to an atomic flag

Browse Source 
tp_loss can be read locklessly.

Convert it to an atomic flag to avoid races.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet 2023-03-16 01:10:11 +00:00 committed by David S. Miller
parent 7438344660
commit 164bddace2
3 changed files with 6 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
net/packet/af_packet.c
View File

@ -2843,7 +2843,7 @@ static int tpacket_snd(struct packet_sock *po, struct msghdr *msg)
if (unlikely(tp_len < 0)) {
tpacket_error:
if (po->tp_loss) {
if (packet_sock_flag(po, PACKET_SOCK_TP_LOSS)) {
__packet_set_status(po, ph,
TP_STATUS_AVAILABLE);
packet_increment_head(&po->tx_ring);
@ -3886,7 +3886,7 @@ packet_setsockopt(struct socket *sock, int level, int optname, sockptr_t optval,
if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) {
ret = -EBUSY;
} else {
po->tp_loss = !!val;
packet_sock_flag_set(po, PACKET_SOCK_TP_LOSS, val);
ret = 0;
}
release_sock(sk);
@ -4095,7 +4095,7 @@ static int packet_getsockopt(struct socket *sock, int level, int optname,
val = po->tp_reserve;
break;
case PACKET_LOSS:
val = po->tp_loss;
val = packet_sock_flag(po, PACKET_SOCK_TP_LOSS);
break;
case PACKET_TIMESTAMP:
val = READ_ONCE(po->tp_tstamp);

2
net/packet/diag.c
View File

@ -29,7 +29,7 @@ static int pdiag_put_info(const struct packet_sock *po, struct sk_buff *nlskb)
pinfo.pdi_flags |= PDI_ORIGDEV;
if (po->has_vnet_hdr)
pinfo.pdi_flags |= PDI_VNETHDR;
if (po->tp_loss)
if (packet_sock_flag(po, PACKET_SOCK_TP_LOSS))
pinfo.pdi_flags |= PDI_LOSS;
return nla_put(nlskb, PACKET_DIAG_INFO, sizeof(pinfo), &pinfo);

4
net/packet/internal.h
View File

@ -118,8 +118,7 @@ struct packet_sock {
struct mutex pg_vec_lock;
unsigned long flags;
unsigned int running; /* bind_lock must be held */
unsigned int has_vnet_hdr:1, /* writer must hold sock lock */
tp_loss:1;
unsigned int has_vnet_hdr:1; /* writer must hold sock lock */
int pressure;
int ifindex; /* bound device */
__be16 num;
@ -146,6 +145,7 @@ enum packet_sock_flags {
PACKET_SOCK_ORIGDEV,
PACKET_SOCK_AUXDATA,
PACKET_SOCK_TX_HAS_OFF,
PACKET_SOCK_TP_LOSS,
};
static inline void packet_sock_flag_set(struct packet_sock *po,