6.1-stable review patch. If anyone has any objections, please let me know.
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From: Eric Dumazet edumazet@google.com
[ Upstream commit 81b36803ac139827538ac5ce4028e750a3c53f53 ]
According to syzbot, it is time to use proper atomic flags for various UDP flags.
Add udp_flags field, and convert udp->corkflag to first bit in it.
Signed-off-by: Eric Dumazet edumazet@google.com Reviewed-by: Willem de Bruijn willemb@google.com Signed-off-by: Paolo Abeni pabeni@redhat.com Stable-dep-of: a0002127cd74 ("udp: move udp->no_check6_tx to udp->udp_flags") Signed-off-by: Sasha Levin sashal@kernel.org --- include/linux/udp.h | 28 +++++++++++++++++++++------- net/ipv4/udp.c | 12 ++++++------ net/ipv6/udp.c | 6 +++--- 3 files changed, 30 insertions(+), 16 deletions(-)
diff --git a/include/linux/udp.h b/include/linux/udp.h index e96da4157d04d..10b56b8231e3c 100644 --- a/include/linux/udp.h +++ b/include/linux/udp.h @@ -30,14 +30,20 @@ static inline u32 udp_hashfn(const struct net *net, u32 num, u32 mask) return (num + net_hash_mix(net)) & mask; }
+enum { + UDP_FLAGS_CORK, /* Cork is required */ +}; + struct udp_sock { /* inet_sock has to be the first member */ struct inet_sock inet; #define udp_port_hash inet.sk.__sk_common.skc_u16hashes[0] #define udp_portaddr_hash inet.sk.__sk_common.skc_u16hashes[1] #define udp_portaddr_node inet.sk.__sk_common.skc_portaddr_node + + unsigned long udp_flags; + int pending; /* Any pending frames ? */ - unsigned int corkflag; /* Cork is required */ __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? */ @@ -49,6 +55,11 @@ struct udp_sock { gro_enabled:1, /* Request GRO aggregation */ accept_udp_l4:1, accept_udp_fraglist:1; +/* indicator bits used by pcflag: */ +#define UDPLITE_BIT 0x1 /* set by udplite proto init function */ +#define UDPLITE_SEND_CC 0x2 /* set via udplite setsockopt */ +#define UDPLITE_RECV_CC 0x4 /* set via udplite setsocktopt */ + __u8 pcflag; /* marks socket as UDP-Lite if > 0 */ /* * Following member retains the information to create a UDP header * when the socket is uncorked. @@ -60,12 +71,6 @@ struct udp_sock { */ __u16 pcslen; __u16 pcrlen; -/* indicator bits used by pcflag: */ -#define UDPLITE_BIT 0x1 /* set by udplite proto init function */ -#define UDPLITE_SEND_CC 0x2 /* set via udplite setsockopt */ -#define UDPLITE_RECV_CC 0x4 /* set via udplite setsocktopt */ - __u8 pcflag; /* marks socket as UDP-Lite if > 0 */ - __u8 unused[3]; /* * For encapsulation sockets. */ @@ -89,6 +94,15 @@ struct udp_sock { int forward_deficit; };
+#define udp_test_bit(nr, sk) \ + test_bit(UDP_FLAGS_##nr, &udp_sk(sk)->udp_flags) +#define udp_set_bit(nr, sk) \ + set_bit(UDP_FLAGS_##nr, &udp_sk(sk)->udp_flags) +#define udp_clear_bit(nr, sk) \ + clear_bit(UDP_FLAGS_##nr, &udp_sk(sk)->udp_flags) +#define udp_assign_bit(nr, sk, val) \ + assign_bit(UDP_FLAGS_##nr, &udp_sk(sk)->udp_flags, val) + #define UDP_MAX_SEGMENTS (1 << 6UL)
static inline struct udp_sock *udp_sk(const struct sock *sk) diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index e8dd2880ac9aa..60a754477efb2 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -1068,7 +1068,7 @@ int udp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) __be16 dport; u8 tos; int err, is_udplite = IS_UDPLITE(sk); - int corkreq = READ_ONCE(up->corkflag) || msg->msg_flags&MSG_MORE; + int corkreq = udp_test_bit(CORK, sk) || msg->msg_flags & MSG_MORE; int (*getfrag)(void *, char *, int, int, int, struct sk_buff *); struct sk_buff *skb; struct ip_options_data opt_copy; @@ -1337,11 +1337,11 @@ void udp_splice_eof(struct socket *sock) struct sock *sk = sock->sk; struct udp_sock *up = udp_sk(sk);
- if (!up->pending || READ_ONCE(up->corkflag)) + if (!up->pending || udp_test_bit(CORK, sk)) return;
lock_sock(sk); - if (up->pending && !READ_ONCE(up->corkflag)) + if (up->pending && !udp_test_bit(CORK, sk)) udp_push_pending_frames(sk); release_sock(sk); } @@ -2673,9 +2673,9 @@ int udp_lib_setsockopt(struct sock *sk, int level, int optname, switch (optname) { case UDP_CORK: if (val != 0) { - WRITE_ONCE(up->corkflag, 1); + udp_set_bit(CORK, sk); } else { - WRITE_ONCE(up->corkflag, 0); + udp_clear_bit(CORK, sk); lock_sock(sk); push_pending_frames(sk); release_sock(sk); @@ -2800,7 +2800,7 @@ int udp_lib_getsockopt(struct sock *sk, int level, int optname,
switch (optname) { case UDP_CORK: - val = READ_ONCE(up->corkflag); + val = udp_test_bit(CORK, sk); break;
case UDP_ENCAP: diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c index 2a65136dca773..85653e3a04fe8 100644 --- a/net/ipv6/udp.c +++ b/net/ipv6/udp.c @@ -1351,7 +1351,7 @@ int udpv6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) int addr_len = msg->msg_namelen; bool connected = false; int ulen = len; - int corkreq = READ_ONCE(up->corkflag) || msg->msg_flags&MSG_MORE; + int corkreq = udp_test_bit(CORK, sk) || msg->msg_flags & MSG_MORE; int err; int is_udplite = IS_UDPLITE(sk); int (*getfrag)(void *, char *, int, int, int, struct sk_buff *); @@ -1662,11 +1662,11 @@ static void udpv6_splice_eof(struct socket *sock) struct sock *sk = sock->sk; struct udp_sock *up = udp_sk(sk);
- if (!up->pending || READ_ONCE(up->corkflag)) + if (!up->pending || udp_test_bit(CORK, sk)) return;
lock_sock(sk); - if (up->pending && !READ_ONCE(up->corkflag)) + if (up->pending && !udp_test_bit(CORK, sk)) udp_v6_push_pending_frames(sk); release_sock(sk); }