1 files changed, 248 insertions, 116 deletions

diff --git a/include/linux/skmsg.h b/include/linux/skmsg.h
index 178a3933a71b..49847888c287 100644
--- a/include/linux/skmsg.h
+++ b/include/linux/skmsg.h
@@ -14,6 +14,7 @@
 #include <net/strparser.h>
 
 #define MAX_MSG_FRAGS			MAX_SKB_FRAGS
+#define NR_MSG_FRAG_IDS			(MAX_MSG_FRAGS + 1)
 
 enum __sk_action {
 	__SK_DROP = 0,
@@ -28,12 +29,14 @@ struct sk_msg_sg {
 	u32				end;
 	u32				size;
 	u32				copybreak;
-	bool				copy[MAX_MSG_FRAGS];
-	/* The extra element is used for chaining the front and sections when
-	 * the list becomes partitioned (e.g. end < start). The crypto APIs
-	 * require the chaining.
+	DECLARE_BITMAP(copy, MAX_MSG_FRAGS + 2);
+	/* The extra two elements:
+	 * 1) used for chaining the front and sections when the list becomes
+	 *    partitioned (e.g. end < start). The crypto APIs require the
+	 *    chaining;
+	 * 2) to chain tailer SG entries after the message.
 	 */
-	struct scatterlist		data[MAX_MSG_FRAGS + 1];
+	struct scatterlist		data[MAX_MSG_FRAGS + 2];
 };
 
 /* UAPI in filter.c depends on struct sk_msg_sg being first element. */
@@ -52,12 +55,18 @@ struct sk_msg {
 
 struct sk_psock_progs {
 	struct bpf_prog			*msg_parser;
-	struct bpf_prog			*skb_parser;
+	struct bpf_prog			*stream_parser;
+	struct bpf_prog			*stream_verdict;
 	struct bpf_prog			*skb_verdict;
+	struct bpf_link			*msg_parser_link;
+	struct bpf_link			*stream_parser_link;
+	struct bpf_link			*stream_verdict_link;
+	struct bpf_link			*skb_verdict_link;
 };
 
 enum sk_psock_state_bits {
 	SK_PSOCK_TX_ENABLED,
+	SK_PSOCK_RX_STRP_ENABLED,
 };
 
 struct sk_psock_link {
@@ -66,14 +75,7 @@ struct sk_psock_link {
 	void				*link_raw;
 };
 
-struct sk_psock_parser {
-	struct strparser		strp;
-	bool				enabled;
-	void (*saved_data_ready)(struct sock *sk);
-};
-
 struct sk_psock_work_state {
-	struct sk_buff			*skb;
 	u32				len;
 	u32				off;
 };
@@ -84,25 +86,39 @@ struct sk_psock {
 	u32				apply_bytes;
 	u32				cork_bytes;
 	u32				eval;
+	bool				redir_ingress; /* undefined if sk_redir is null */
 	struct sk_msg			*cork;
 	struct sk_psock_progs		progs;
-	struct sk_psock_parser		parser;
+#if IS_ENABLED(CONFIG_BPF_STREAM_PARSER)
+	struct strparser		strp;
+	u32				copied_seq;
+	u32				ingress_bytes;
+#endif
 	struct sk_buff_head		ingress_skb;
 	struct list_head		ingress_msg;
+	spinlock_t			ingress_lock;
 	unsigned long			state;
 	struct list_head		link;
 	spinlock_t			link_lock;
 	refcount_t			refcnt;
 	void (*saved_unhash)(struct sock *sk);
+	void (*saved_destroy)(struct sock *sk);
 	void (*saved_close)(struct sock *sk, long timeout);
 	void (*saved_write_space)(struct sock *sk);
+	void (*saved_data_ready)(struct sock *sk);
+	/* psock_update_sk_prot may be called with restore=false many times
+	 * so the handler must be safe for this case. It will be called
+	 * exactly once with restore=true when the psock is being destroyed
+	 * and psock refcnt is zero, but before an RCU grace period.
+	 */
+	int  (*psock_update_sk_prot)(struct sock *sk, struct sk_psock *psock,
+				     bool restore);
 	struct proto			*sk_proto;
+	struct mutex			work_mutex;
 	struct sk_psock_work_state	work_state;
-	struct work_struct		work;
-	union {
-		struct rcu_head		rcu;
-		struct work_struct	gc;
-	};
+	struct delayed_work		work;
+	struct sock			*sk_pair;
+	struct rcu_work			rwork;
 };
 
 int sk_msg_alloc(struct sock *sk, struct sk_msg *msg, int len,
@@ -123,6 +139,9 @@ int sk_msg_zerocopy_from_iter(struct sock *sk, struct iov_iter *from,
 			      struct sk_msg *msg, u32 bytes);
 int sk_msg_memcopy_from_iter(struct sock *sk, struct iov_iter *from,
 			     struct sk_msg *msg, u32 bytes);
+int sk_msg_recvmsg(struct sock *sk, struct sk_psock *psock, struct msghdr *msg,
+		   int len, int flags);
+bool sk_msg_is_readable(struct sock *sk);
 
 static inline void sk_msg_check_to_free(struct sk_msg *msg, u32 i, u32 bytes)
 {
@@ -139,10 +158,15 @@ static inline void sk_msg_apply_bytes(struct sk_psock *psock, u32 bytes)
 	}
 }
 
+static inline u32 sk_msg_iter_dist(u32 start, u32 end)
+{
+	return end >= start ? end - start : end + (NR_MSG_FRAG_IDS - start);
+}
+
 #define sk_msg_iter_var_prev(var)			\
 	do {						\
 		if (var == 0)				\
-			var = MAX_MSG_FRAGS - 1;	\
+			var = NR_MSG_FRAG_IDS - 1;	\
 		else					\
 			var--;				\
 	} while (0)
@@ -150,7 +174,7 @@ static inline void sk_msg_apply_bytes(struct sk_psock *psock, u32 bytes)
 #define sk_msg_iter_var_next(var)			\
 	do {						\
 		var++;					\
-		if (var == MAX_MSG_FRAGS)		\
+		if (var == NR_MSG_FRAG_IDS)		\
 			var = 0;			\
 	} while (0)
 
@@ -160,16 +184,11 @@ static inline void sk_msg_apply_bytes(struct sk_psock *psock, u32 bytes)
 #define sk_msg_iter_next(msg, which)			\
 	sk_msg_iter_var_next(msg->sg.which)
 
-static inline void sk_msg_clear_meta(struct sk_msg *msg)
-{
-	memset(&msg->sg, 0, offsetofend(struct sk_msg_sg, copy));
-}
-
 static inline void sk_msg_init(struct sk_msg *msg)
 {
-	BUILD_BUG_ON(ARRAY_SIZE(msg->sg.data) - 1 != MAX_MSG_FRAGS);
+	BUILD_BUG_ON(ARRAY_SIZE(msg->sg.data) - 1 != NR_MSG_FRAG_IDS);
 	memset(msg, 0, sizeof(*msg));
-	sg_init_marker(msg->sg.data, MAX_MSG_FRAGS);
+	sg_init_marker(msg->sg.data, NR_MSG_FRAG_IDS);
 }
 
 static inline void sk_msg_xfer(struct sk_msg *dst, struct sk_msg *src,
@@ -178,6 +197,7 @@ static inline void sk_msg_xfer(struct sk_msg *dst, struct sk_msg *src,
 	dst->sg.data[which] = src->sg.data[which];
 	dst->sg.data[which].length  = size;
 	dst->sg.size		   += size;
+	src->sg.size		   -= size;
 	src->sg.data[which].length -= size;
 	src->sg.data[which].offset += size;
 }
@@ -190,17 +210,12 @@ static inline void sk_msg_xfer_full(struct sk_msg *dst, struct sk_msg *src)
 
 static inline bool sk_msg_full(const struct sk_msg *msg)
 {
-	return (msg->sg.end == msg->sg.start) && msg->sg.size;
+	return sk_msg_iter_dist(msg->sg.start, msg->sg.end) == MAX_MSG_FRAGS;
 }
 
 static inline u32 sk_msg_elem_used(const struct sk_msg *msg)
 {
-	if (sk_msg_full(msg))
-		return MAX_MSG_FRAGS;
-
-	return msg->sg.end >= msg->sg.start ?
-		msg->sg.end - msg->sg.start :
-		msg->sg.end + (MAX_MSG_FRAGS - msg->sg.start);
+	return sk_msg_iter_dist(msg->sg.start, msg->sg.end);
 }
 
 static inline struct scatterlist *sk_msg_elem(struct sk_msg *msg, int which)
@@ -227,7 +242,7 @@ static inline void sk_msg_compute_data_pointers(struct sk_msg *msg)
 {
 	struct scatterlist *sge = sk_msg_elem(msg, msg->sg.start);
 
-	if (msg->sg.copy[msg->sg.start]) {
+	if (test_bit(msg->sg.start, msg->sg.copy)) {
 		msg->data = NULL;
 		msg->data_end = NULL;
 	} else {
@@ -246,7 +261,7 @@ static inline void sk_msg_page_add(struct sk_msg *msg, struct page *page,
 	sg_set_page(sge, page, len, offset);
 	sg_unmark_end(sge);
 
-	msg->sg.copy[msg->sg.end] = true;
+	__set_bit(msg->sg.end, msg->sg.copy);
 	msg->sg.size += len;
 	sk_msg_iter_next(msg, end);
 }
@@ -254,7 +269,10 @@ static inline void sk_msg_page_add(struct sk_msg *msg, struct page *page,
 static inline void sk_msg_sg_copy(struct sk_msg *msg, u32 i, bool copy_state)
 {
 	do {
-		msg->sg.copy[i] = copy_state;
+		if (copy_state)
+			__set_bit(i, msg->sg.copy);
+		else
+			__clear_bit(i, msg->sg.copy);
 		sk_msg_iter_var_next(i);
 		if (i == msg->sg.end)
 			break;
@@ -273,13 +291,86 @@ static inline void sk_msg_sg_copy_clear(struct sk_msg *msg, u32 start)
 
 static inline struct sk_psock *sk_psock(const struct sock *sk)
 {
-	return rcu_dereference_sk_user_data(sk);
+	return __rcu_dereference_sk_user_data_with_flags(sk,
+							 SK_USER_DATA_PSOCK);
+}
+
+static inline void sk_psock_set_state(struct sk_psock *psock,
+				      enum sk_psock_state_bits bit)
+{
+	set_bit(bit, &psock->state);
+}
+
+static inline void sk_psock_clear_state(struct sk_psock *psock,
+					enum sk_psock_state_bits bit)
+{
+	clear_bit(bit, &psock->state);
+}
+
+static inline bool sk_psock_test_state(const struct sk_psock *psock,
+				       enum sk_psock_state_bits bit)
+{
+	return test_bit(bit, &psock->state);
+}
+
+static inline void sock_drop(struct sock *sk, struct sk_buff *skb)
+{
+	sk_drops_skbadd(sk, skb);
+	kfree_skb(skb);
 }
 
-static inline void sk_psock_queue_msg(struct sk_psock *psock,
+static inline bool sk_psock_queue_msg(struct sk_psock *psock,
 				      struct sk_msg *msg)
 {
-	list_add_tail(&msg->list, &psock->ingress_msg);
+	bool ret;
+
+	spin_lock_bh(&psock->ingress_lock);
+	if (sk_psock_test_state(psock, SK_PSOCK_TX_ENABLED)) {
+		list_add_tail(&msg->list, &psock->ingress_msg);
+		ret = true;
+	} else {
+		sk_msg_free(psock->sk, msg);
+		kfree(msg);
+		ret = false;
+	}
+	spin_unlock_bh(&psock->ingress_lock);
+	return ret;
+}
+
+static inline struct sk_msg *sk_psock_dequeue_msg(struct sk_psock *psock)
+{
+	struct sk_msg *msg;
+
+	spin_lock_bh(&psock->ingress_lock);
+	msg = list_first_entry_or_null(&psock->ingress_msg, struct sk_msg, list);
+	if (msg)
+		list_del(&msg->list);
+	spin_unlock_bh(&psock->ingress_lock);
+	return msg;
+}
+
+static inline struct sk_msg *sk_psock_peek_msg(struct sk_psock *psock)
+{
+	struct sk_msg *msg;
+
+	spin_lock_bh(&psock->ingress_lock);
+	msg = list_first_entry_or_null(&psock->ingress_msg, struct sk_msg, list);
+	spin_unlock_bh(&psock->ingress_lock);
+	return msg;
+}
+
+static inline struct sk_msg *sk_psock_next_msg(struct sk_psock *psock,
+					       struct sk_msg *msg)
+{
+	struct sk_msg *ret;
+
+	spin_lock_bh(&psock->ingress_lock);
+	if (list_is_last(&msg->list, &psock->ingress_msg))
+		ret = NULL;
+	else
+		ret = list_next_entry(msg, list);
+	spin_unlock_bh(&psock->ingress_lock);
+	return ret;
 }
 
 static inline bool sk_psock_queue_empty(const struct sk_psock *psock)
@@ -287,28 +378,57 @@ static inline bool sk_psock_queue_empty(const struct sk_psock *psock)
 	return psock ? list_empty(&psock->ingress_msg) : true;
 }
 
+static inline void kfree_sk_msg(struct sk_msg *msg)
+{
+	if (msg->skb)
+		consume_skb(msg->skb);
+	kfree(msg);
+}
+
 static inline void sk_psock_report_error(struct sk_psock *psock, int err)
 {
 	struct sock *sk = psock->sk;
 
 	sk->sk_err = err;
-	sk->sk_error_report(sk);
+	sk_error_report(sk);
 }
 
 struct sk_psock *sk_psock_init(struct sock *sk, int node);
+void sk_psock_stop(struct sk_psock *psock);
 
+#if IS_ENABLED(CONFIG_BPF_STREAM_PARSER)
 int sk_psock_init_strp(struct sock *sk, struct sk_psock *psock);
 void sk_psock_start_strp(struct sock *sk, struct sk_psock *psock);
 void sk_psock_stop_strp(struct sock *sk, struct sk_psock *psock);
+#else
+static inline int sk_psock_init_strp(struct sock *sk, struct sk_psock *psock)
+{
+	return -EOPNOTSUPP;
+}
 
-int sk_psock_msg_verdict(struct sock *sk, struct sk_psock *psock,
-			 struct sk_msg *msg);
+static inline void sk_psock_start_strp(struct sock *sk, struct sk_psock *psock)
+{
+}
 
-static inline struct sk_psock_link *sk_psock_init_link(void)
+static inline void sk_psock_stop_strp(struct sock *sk, struct sk_psock *psock)
 {
-	return kzalloc(sizeof(struct sk_psock_link),
-		       GFP_ATOMIC | __GFP_NOWARN);
 }
+#endif
+
+void sk_psock_start_verdict(struct sock *sk, struct sk_psock *psock);
+void sk_psock_stop_verdict(struct sock *sk, struct sk_psock *psock);
+
+int sk_psock_msg_verdict(struct sock *sk, struct sk_psock *psock,
+			 struct sk_msg *msg);
+
+/*
+ * This specialized allocator has to be a macro for its allocations to be
+ * accounted separately (to have a separate alloc_tag). The typecast is
+ * intentional to enforce typesafety.
+ */
+#define sk_psock_init_link()	\
+		((struct sk_psock_link *)kzalloc(sizeof(struct sk_psock_link),	\
+						 GFP_ATOMIC | __GFP_NOWARN))
 
 static inline void sk_psock_free_link(struct sk_psock_link *link)
 {
@@ -316,16 +436,6 @@ static inline void sk_psock_free_link(struct sk_psock_link *link)
 }
 
 struct sk_psock_link *sk_psock_link_pop(struct sk_psock *psock);
-#if defined(CONFIG_BPF_STREAM_PARSER)
-void sk_psock_unlink(struct sock *sk, struct sk_psock_link *link);
-#else
-static inline void sk_psock_unlink(struct sock *sk,
-				   struct sk_psock_link *link)
-{
-}
-#endif
-
-void __sk_psock_purge_ingress_msg(struct sk_psock *psock);
 
 static inline void sk_psock_cork_free(struct sk_psock *psock)
 {
@@ -336,63 +446,11 @@ static inline void sk_psock_cork_free(struct sk_psock *psock)
 	}
 }
 
-static inline void sk_psock_update_proto(struct sock *sk,
-					 struct sk_psock *psock,
-					 struct proto *ops)
-{
-	psock->saved_unhash = sk->sk_prot->unhash;
-	psock->saved_close = sk->sk_prot->close;
-	psock->saved_write_space = sk->sk_write_space;
-
-	psock->sk_proto = sk->sk_prot;
-	sk->sk_prot = ops;
-}
-
 static inline void sk_psock_restore_proto(struct sock *sk,
 					  struct sk_psock *psock)
 {
-	if (psock->sk_proto) {
-		sk->sk_prot = psock->sk_proto;
-		psock->sk_proto = NULL;
-	}
-}
-
-static inline void sk_psock_set_state(struct sk_psock *psock,
-				      enum sk_psock_state_bits bit)
-{
-	set_bit(bit, &psock->state);
-}
-
-static inline void sk_psock_clear_state(struct sk_psock *psock,
-					enum sk_psock_state_bits bit)
-{
-	clear_bit(bit, &psock->state);
-}
-
-static inline bool sk_psock_test_state(const struct sk_psock *psock,
-				       enum sk_psock_state_bits bit)
-{
-	return test_bit(bit, &psock->state);
-}
-
-static inline struct sk_psock *sk_psock_get_checked(struct sock *sk)
-{
-	struct sk_psock *psock;
-
-	rcu_read_lock();
-	psock = sk_psock(sk);
-	if (psock) {
-		if (sk->sk_prot->recvmsg != tcp_bpf_recvmsg) {
-			psock = ERR_PTR(-EBUSY);
-			goto out;
-		}
-
-		if (!refcount_inc_not_zero(&psock->refcnt))
-			psock = ERR_PTR(-EBUSY);
-	}
-out:
-	rcu_read_unlock();
-	return psock;
+	if (psock->psock_update_sk_prot)
+		psock->psock_update_sk_prot(sk, psock, true);
 }
 
 static inline struct sk_psock *sk_psock_get(struct sock *sk)
@@ -407,8 +465,6 @@ static inline struct sk_psock *sk_psock_get(struct sock *sk)
 	return psock;
 }
 
-void sk_psock_stop(struct sock *sk, struct sk_psock *psock);
-void sk_psock_destroy(struct rcu_head *rcu);
 void sk_psock_drop(struct sock *sk, struct sk_psock *psock);
 
 static inline void sk_psock_put(struct sock *sk, struct sk_psock *psock)
@@ -419,10 +475,12 @@ static inline void sk_psock_put(struct sock *sk, struct sk_psock *psock)
 
 static inline void sk_psock_data_ready(struct sock *sk, struct sk_psock *psock)
 {
-	if (psock->parser.enabled)
-		psock->parser.saved_data_ready(sk);
+	read_lock_bh(&sk->sk_callback_lock);
+	if (psock->saved_data_ready)
+		psock->saved_data_ready(sk);
 	else
 		sk->sk_data_ready(sk);
+	read_unlock_bh(&sk->sk_callback_lock);
 }
 
 static inline void psock_set_prog(struct bpf_prog **pprog,
@@ -433,11 +491,85 @@ static inline void psock_set_prog(struct bpf_prog **pprog,
 		bpf_prog_put(prog);
 }
 
+static inline int psock_replace_prog(struct bpf_prog **pprog,
+				     struct bpf_prog *prog,
+				     struct bpf_prog *old)
+{
+	if (cmpxchg(pprog, old, prog) != old)
+		return -ENOENT;
+
+	if (old)
+		bpf_prog_put(old);
+
+	return 0;
+}
+
 static inline void psock_progs_drop(struct sk_psock_progs *progs)
 {
 	psock_set_prog(&progs->msg_parser, NULL);
-	psock_set_prog(&progs->skb_parser, NULL);
+	psock_set_prog(&progs->stream_parser, NULL);
+	psock_set_prog(&progs->stream_verdict, NULL);
 	psock_set_prog(&progs->skb_verdict, NULL);
 }
 
+int sk_psock_tls_strp_read(struct sk_psock *psock, struct sk_buff *skb);
+
+static inline bool sk_psock_strp_enabled(struct sk_psock *psock)
+{
+	if (!psock)
+		return false;
+	return !!psock->saved_data_ready;
+}
+
+#if IS_ENABLED(CONFIG_NET_SOCK_MSG)
+
+#define BPF_F_STRPARSER	(1UL << 1)
+
+/* We only have two bits so far. */
+#define BPF_F_PTR_MASK ~(BPF_F_INGRESS | BPF_F_STRPARSER)
+
+static inline bool skb_bpf_strparser(const struct sk_buff *skb)
+{
+	unsigned long sk_redir = skb->_sk_redir;
+
+	return sk_redir & BPF_F_STRPARSER;
+}
+
+static inline void skb_bpf_set_strparser(struct sk_buff *skb)
+{
+	skb->_sk_redir |= BPF_F_STRPARSER;
+}
+
+static inline bool skb_bpf_ingress(const struct sk_buff *skb)
+{
+	unsigned long sk_redir = skb->_sk_redir;
+
+	return sk_redir & BPF_F_INGRESS;
+}
+
+static inline void skb_bpf_set_ingress(struct sk_buff *skb)
+{
+	skb->_sk_redir |= BPF_F_INGRESS;
+}
+
+static inline void skb_bpf_set_redir(struct sk_buff *skb, struct sock *sk_redir,
+				     bool ingress)
+{
+	skb->_sk_redir = (unsigned long)sk_redir;
+	if (ingress)
+		skb->_sk_redir |= BPF_F_INGRESS;
+}
+
+static inline struct sock *skb_bpf_redirect_fetch(const struct sk_buff *skb)
+{
+	unsigned long sk_redir = skb->_sk_redir;
+
+	return (struct sock *)(sk_redir & BPF_F_PTR_MASK);
+}
+
+static inline void skb_bpf_redirect_clear(struct sk_buff *skb)
+{
+	skb->_sk_redir = 0;
+}
+#endif /* CONFIG_NET_SOCK_MSG */
 #endif /* _LINUX_SKMSG_H */