From: Eric Dumazet <edumazet@xxxxxxxxxx>
[ Upstream commit fd53c297aa7b077ae98a3d3d2d3aa278a1686ba6 ]
po->auxdata can be read while another thread
is changing its value, potentially raising KCSAN splat.
Convert it to PACKET_SOCK_AUXDATA flag.
Fixes: 8dc419447415 ("[PACKET]: Add optional checksum computation for recvmsg")
Signed-off-by: Eric Dumazet <edumazet@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
net/packet/af_packet.c | 8 +++-----
net/packet/diag.c | 2 +-
net/packet/internal.h | 4 ++--
3 files changed, 6 insertions(+), 8 deletions(-)
diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c
index 91c35d45e43ca..60986c209311f 100644
--- a/net/packet/af_packet.c
+++ b/net/packet/af_packet.c
@@ -3444,7 +3444,7 @@ static int packet_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
memcpy(msg->msg_name, &PACKET_SKB_CB(skb)->sa, copy_len);
}
- if (pkt_sk(sk)->auxdata) {
+ if (packet_sock_flag(pkt_sk(sk), PACKET_SOCK_AUXDATA)) {
struct tpacket_auxdata aux;
aux.tp_status = TP_STATUS_USER;
@@ -3827,9 +3827,7 @@ packet_setsockopt(struct socket *sock, int level, int optname, char __user *optv
if (copy_from_user(&val, optval, sizeof(val)))
return -EFAULT;
- lock_sock(sk);
- po->auxdata = !!val;
- release_sock(sk);
+ packet_sock_flag_set(po, PACKET_SOCK_AUXDATA, val);
return 0;
}
case PACKET_ORIGDEV:
@@ -3971,7 +3969,7 @@ static int packet_getsockopt(struct socket *sock, int level, int optname,
break;
case PACKET_AUXDATA:
- val = po->auxdata;
+ val = packet_sock_flag(po, PACKET_SOCK_AUXDATA);
break;
case PACKET_ORIGDEV:
val = packet_sock_flag(po, PACKET_SOCK_ORIGDEV);
diff --git a/net/packet/diag.c b/net/packet/diag.c
index bf5928e5df035..d9f912ad23dfa 100644
--- a/net/packet/diag.c
+++ b/net/packet/diag.c
@@ -22,7 +22,7 @@ static int pdiag_put_info(const struct packet_sock *po, struct sk_buff *nlskb)
pinfo.pdi_flags = 0;
if (po->running)
pinfo.pdi_flags |= PDI_RUNNING;
- if (po->auxdata)
+ if (packet_sock_flag(po, PACKET_SOCK_AUXDATA))
pinfo.pdi_flags |= PDI_AUXDATA;
if (packet_sock_flag(po, PACKET_SOCK_ORIGDEV))
pinfo.pdi_flags |= PDI_ORIGDEV;
diff --git a/net/packet/internal.h b/net/packet/internal.h
index f39dcc7608bc6..3d871cae85b8c 100644
--- a/net/packet/internal.h
+++ b/net/packet/internal.h
@@ -117,8 +117,7 @@ struct packet_sock {
struct mutex pg_vec_lock;
unsigned long flags;
unsigned int running; /* bind_lock must be held */
- unsigned int auxdata:1, /* writer must hold sock lock */
- has_vnet_hdr:1,
+ unsigned int has_vnet_hdr:1, /* writer must hold sock lock */
tp_loss:1,
tp_tx_has_off:1;
int pressure;
@@ -144,6 +143,7 @@ static struct packet_sock *pkt_sk(struct sock *sk)
enum packet_sock_flags {
PACKET_SOCK_ORIGDEV,
+ PACKET_SOCK_AUXDATA,
};
static inline void packet_sock_flag_set(struct packet_sock *po,
--
2.39.2
