[bpf,v3,1/6] bpf: fix unconnected udp hooks

diff --git a/include/linux/bpf-cgroup.h b/include/linux/bpf-cgroup.h
index cb3c6b3b89c8..a7f7a98ec39d 100644
--- a/include/linux/bpf-cgroup.h
+++ b/include/linux/bpf-cgroup.h
@@ -238,6 +238,12 @@  int bpf_percpu_cgroup_storage_update(struct bpf_map *map, void *key,
 #define BPF_CGROUP_RUN_PROG_UDP6_SENDMSG_LOCK(sk, uaddr, t_ctx)		       \
 	BPF_CGROUP_RUN_SA_PROG_LOCK(sk, uaddr, BPF_CGROUP_UDP6_SENDMSG, t_ctx)
 
+#define BPF_CGROUP_RUN_PROG_UDP4_RECVMSG_LOCK(sk, uaddr)			\
+	BPF_CGROUP_RUN_SA_PROG_LOCK(sk, uaddr, BPF_CGROUP_UDP4_RECVMSG, NULL)
+
+#define BPF_CGROUP_RUN_PROG_UDP6_RECVMSG_LOCK(sk, uaddr)			\
+	BPF_CGROUP_RUN_SA_PROG_LOCK(sk, uaddr, BPF_CGROUP_UDP6_RECVMSG, NULL)
+
 #define BPF_CGROUP_RUN_PROG_SOCK_OPS(sock_ops)				       \
 ({									       \
 	int __ret = 0;							       \
@@ -339,6 +345,8 @@  static inline int bpf_percpu_cgroup_storage_update(struct bpf_map *map,
 #define BPF_CGROUP_RUN_PROG_INET6_CONNECT_LOCK(sk, uaddr) ({ 0; })
 #define BPF_CGROUP_RUN_PROG_UDP4_SENDMSG_LOCK(sk, uaddr, t_ctx) ({ 0; })
 #define BPF_CGROUP_RUN_PROG_UDP6_SENDMSG_LOCK(sk, uaddr, t_ctx) ({ 0; })
+#define BPF_CGROUP_RUN_PROG_UDP4_RECVMSG_LOCK(sk, uaddr) ({ 0; })
+#define BPF_CGROUP_RUN_PROG_UDP6_RECVMSG_LOCK(sk, uaddr) ({ 0; })
 #define BPF_CGROUP_RUN_PROG_SOCK_OPS(sock_ops) ({ 0; })
 #define BPF_CGROUP_RUN_PROG_DEVICE_CGROUP(type,major,minor,access) ({ 0; })
 #define BPF_CGROUP_RUN_PROG_SYSCTL(head,table,write,buf,count,pos,nbuf) ({ 0; })
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index 63e0cf66f01a..e4114a7e4451 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -192,6 +192,8 @@  enum bpf_attach_type {
 	BPF_LIRC_MODE2,
 	BPF_FLOW_DISSECTOR,
 	BPF_CGROUP_SYSCTL,
+	BPF_CGROUP_UDP4_RECVMSG,
+	BPF_CGROUP_UDP6_RECVMSG,
 	__MAX_BPF_ATTACH_TYPE
 };
 
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index cb5440b02e82..e8ba3a153691 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -1581,6 +1581,8 @@  bpf_prog_load_check_attach_type(enum bpf_prog_type prog_type,
 		case BPF_CGROUP_INET6_CONNECT:
 		case BPF_CGROUP_UDP4_SENDMSG:
 		case BPF_CGROUP_UDP6_SENDMSG:
+		case BPF_CGROUP_UDP4_RECVMSG:
+		case BPF_CGROUP_UDP6_RECVMSG:
 			return 0;
 		default:
 			return -EINVAL;
@@ -1875,6 +1877,8 @@  static int bpf_prog_attach(const union bpf_attr *attr)
 	case BPF_CGROUP_INET6_CONNECT:
 	case BPF_CGROUP_UDP4_SENDMSG:
 	case BPF_CGROUP_UDP6_SENDMSG:
+	case BPF_CGROUP_UDP4_RECVMSG:
+	case BPF_CGROUP_UDP6_RECVMSG:
 		ptype = BPF_PROG_TYPE_CGROUP_SOCK_ADDR;
 		break;
 	case BPF_CGROUP_SOCK_OPS:
@@ -1960,6 +1964,8 @@  static int bpf_prog_detach(const union bpf_attr *attr)
 	case BPF_CGROUP_INET6_CONNECT:
 	case BPF_CGROUP_UDP4_SENDMSG:
 	case BPF_CGROUP_UDP6_SENDMSG:
+	case BPF_CGROUP_UDP4_RECVMSG:
+	case BPF_CGROUP_UDP6_RECVMSG:
 		ptype = BPF_PROG_TYPE_CGROUP_SOCK_ADDR;
 		break;
 	case BPF_CGROUP_SOCK_OPS:
@@ -2011,6 +2017,8 @@  static int bpf_prog_query(const union bpf_attr *attr,
 	case BPF_CGROUP_INET6_CONNECT:
 	case BPF_CGROUP_UDP4_SENDMSG:
 	case BPF_CGROUP_UDP6_SENDMSG:
+	case BPF_CGROUP_UDP4_RECVMSG:
+	case BPF_CGROUP_UDP6_RECVMSG:
 	case BPF_CGROUP_SOCK_OPS:
 	case BPF_CGROUP_DEVICE:
 	case BPF_CGROUP_SYSCTL:
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 95f9354495ad..d2c8a6677ac4 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -5361,9 +5361,12 @@  static int check_return_code(struct bpf_verifier_env *env)
 	struct tnum range = tnum_range(0, 1);
 
 	switch (env->prog->type) {
+	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
+		if (env->prog->expected_attach_type == BPF_CGROUP_UDP4_RECVMSG ||
+		    env->prog->expected_attach_type == BPF_CGROUP_UDP6_RECVMSG)
+			range = tnum_range(1, 1);
 	case BPF_PROG_TYPE_CGROUP_SKB:
 	case BPF_PROG_TYPE_CGROUP_SOCK:
-	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
 	case BPF_PROG_TYPE_SOCK_OPS:
 	case BPF_PROG_TYPE_CGROUP_DEVICE:
 	case BPF_PROG_TYPE_CGROUP_SYSCTL:
@@ -5380,16 +5383,17 @@  static int check_return_code(struct bpf_verifier_env *env)
 	}
 
 	if (!tnum_in(range, reg->var_off)) {
+		char tn_buf[48];
+
 		verbose(env, "At program exit the register R0 ");
 		if (!tnum_is_unknown(reg->var_off)) {
-			char tn_buf[48];
-
 			tnum_strn(tn_buf, sizeof(tn_buf), reg->var_off);
 			verbose(env, "has value %s", tn_buf);
 		} else {
 			verbose(env, "has unknown scalar value");
 		}
-		verbose(env, " should have been 0 or 1\n");
+		tnum_strn(tn_buf, sizeof(tn_buf), range);
+		verbose(env, " should have been in %s\n", tn_buf);
 		return -EINVAL;
 	}
 	return 0;
diff --git a/net/core/filter.c b/net/core/filter.c
index fdcc504d2dec..2814d785c110 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -6748,6 +6748,7 @@  static bool sock_addr_is_valid_access(int off, int size,
 		case BPF_CGROUP_INET4_BIND:
 		case BPF_CGROUP_INET4_CONNECT:
 		case BPF_CGROUP_UDP4_SENDMSG:
+		case BPF_CGROUP_UDP4_RECVMSG:
 			break;
 		default:
 			return false;
@@ -6758,6 +6759,7 @@  static bool sock_addr_is_valid_access(int off, int size,
 		case BPF_CGROUP_INET6_BIND:
 		case BPF_CGROUP_INET6_CONNECT:
 		case BPF_CGROUP_UDP6_SENDMSG:
+		case BPF_CGROUP_UDP6_RECVMSG:
 			break;
 		default:
 			return false;
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index 85db0e3d7f3f..2d862823cbb7 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -1783,6 +1783,10 @@  int udp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, int noblock,
 		sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
 		memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
 		*addr_len = sizeof(*sin);
+
+		if (cgroup_bpf_enabled)
+			BPF_CGROUP_RUN_PROG_UDP4_RECVMSG_LOCK(sk,
+							(struct sockaddr *)sin);
 	}
 
 	if (udp_sk(sk)->gro_enabled)
diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index 4e52c37bb836..15570d7b9b61 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -369,6 +369,10 @@  int udpv6_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
 						    inet6_iif(skb));
 		}
 		*addr_len = sizeof(*sin6);
+
+		if (cgroup_bpf_enabled)
+			BPF_CGROUP_RUN_PROG_UDP6_RECVMSG_LOCK(sk,
+						(struct sockaddr *)sin6);
 	}
 
 	if (udp_sk(sk)->gro_enabled)