udp: move udp->no_check6_tx to udp->udp_flags

[ Upstream commit a0002127cd746fcaa182ad3386ef6931c37f3bda ]

syzbot reported that udp->no_check6_tx can be read locklessly.
Use one atomic bit from udp->udp_flags

Fixes: 1c19448c9b ("net: Make enabling of zero UDP6 csums more restrictive")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Eric Dumazet 2023-09-12 09:17:22 +00:00 committed by Greg Kroah-Hartman
parent e2a4392b61
commit 50e41aa9ea
3 changed files with 9 additions and 9 deletions

View File

@ -32,6 +32,7 @@ static inline u32 udp_hashfn(const struct net *net, u32 num, u32 mask)
enum {
UDP_FLAGS_CORK, /* Cork is required */
UDP_FLAGS_NO_CHECK6_TX, /* Send zero UDP6 checksums on TX? */
};
struct udp_sock {
@ -45,8 +46,7 @@ struct udp_sock {
int pending; /* Any pending frames ? */
__u8 encap_type; /* Is this an Encapsulation socket? */
unsigned char no_check6_tx:1,/* Send zero UDP6 checksums on TX? */
no_check6_rx:1,/* Allow zero UDP6 checksums on RX? */
unsigned char no_check6_rx:1,/* Allow zero UDP6 checksums on RX? */
encap_enabled:1, /* This socket enabled encap
* processing; UDP tunnels and
* different encapsulation layer set
@ -112,7 +112,7 @@ static inline struct udp_sock *udp_sk(const struct sock *sk)
static inline void udp_set_no_check6_tx(struct sock *sk, bool val)
{
udp_sk(sk)->no_check6_tx = val;
udp_assign_bit(NO_CHECK6_TX, sk, val);
}
static inline void udp_set_no_check6_rx(struct sock *sk, bool val)
@ -120,9 +120,9 @@ static inline void udp_set_no_check6_rx(struct sock *sk, bool val)
udp_sk(sk)->no_check6_rx = val;
}
static inline bool udp_get_no_check6_tx(struct sock *sk)
static inline bool udp_get_no_check6_tx(const struct sock *sk)
{
return udp_sk(sk)->no_check6_tx;
return udp_test_bit(NO_CHECK6_TX, sk);
}
static inline bool udp_get_no_check6_rx(struct sock *sk)

View File

@ -2711,7 +2711,7 @@ int udp_lib_setsockopt(struct sock *sk, int level, int optname,
break;
case UDP_NO_CHECK6_TX:
up->no_check6_tx = valbool;
udp_set_no_check6_tx(sk, valbool);
break;
case UDP_NO_CHECK6_RX:
@ -2808,7 +2808,7 @@ int udp_lib_getsockopt(struct sock *sk, int level, int optname,
break;
case UDP_NO_CHECK6_TX:
val = up->no_check6_tx;
val = udp_get_no_check6_tx(sk);
break;
case UDP_NO_CHECK6_RX:

View File

@ -1260,7 +1260,7 @@ static int udp_v6_send_skb(struct sk_buff *skb, struct flowi6 *fl6,
kfree_skb(skb);
return -EINVAL;
}
if (udp_sk(sk)->no_check6_tx) {
if (udp_get_no_check6_tx(sk)) {
kfree_skb(skb);
return -EINVAL;
}
@ -1281,7 +1281,7 @@ static int udp_v6_send_skb(struct sk_buff *skb, struct flowi6 *fl6,
if (is_udplite)
csum = udplite_csum(skb);
else if (udp_sk(sk)->no_check6_tx) { /* UDP csum disabled */
else if (udp_get_no_check6_tx(sk)) { /* UDP csum disabled */
skb->ip_summed = CHECKSUM_NONE;
goto send;
} else if (skb->ip_summed == CHECKSUM_PARTIAL) { /* UDP hardware csum */