From: Eric Dumazet <edumazet@google.com> stable inclusion from stable-v6.6.2 commit 39fc39a0c5907a07b8505f73b11532b72ed6e9c4 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I8IW7G Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- [ Upstream commit a0002127cd746fcaa182ad3386ef6931c37f3bda ] syzbot reported that udp->no_check6_tx can be read locklessly. Use one atomic bit from udp->udp_flags Fixes: 1c19448c9ba6 ("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> Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com> --- include/linux/udp.h | 10 +++++----- net/ipv4/udp.c | 4 ++-- net/ipv6/udp.c | 4 ++-- 3 files changed, 9 insertions(+), 9 deletions(-) diff --git a/include/linux/udp.h b/include/linux/udp.h index 23f0693e0d9c..e3f2a6c7ac1d 100644 --- a/include/linux/udp.h +++ b/include/linux/udp.h @@ -34,6 +34,7 @@ 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 { @@ -47,8 +48,7 @@ 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 @@ -115,7 +115,7 @@ struct udp_sock { 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) @@ -123,9 +123,9 @@ 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) diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index 9709f8a532dc..0c6998291c99 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -2694,7 +2694,7 @@ 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: @@ -2791,7 +2791,7 @@ 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: diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c index 0c6973cd22ce..469df0ca561f 100644 --- a/net/ipv6/udp.c +++ b/net/ipv6/udp.c @@ -1241,7 +1241,7 @@ 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; } @@ -1262,7 +1262,7 @@ 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 */ -- 2.25.1