Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

Alexei Starovoitov says:

====================
pull-request: bpf-next 2021-04-23

The following pull-request contains BPF updates for your *net-next* tree.

We've added 69 non-merge commits during the last 22 day(s) which contain
a total of 69 files changed, 3141 insertions(+), 866 deletions(-).

The main changes are:

1) Add BPF static linker support for extern resolution of global, from Andrii.

2) Refine retval for bpf_get_task_stack helper, from Dave.

3) Add a bpf_snprintf helper, from Florent.

4) A bunch of miscellaneous improvements from many developers.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

8 files changed, 107 insertions, 7 deletions

diff --git a/include/linux/bpf-cgroup.h b/include/linux/bpf-cgroup.h
index 6a29fe11485d..8b77d08d4b47 100644
--- a/include/linux/bpf-cgroup.h
+++ b/include/linux/bpf-cgroup.h
@@ -458,7 +458,6 @@ int cgroup_bpf_prog_query(const union bpf_attr *attr,
 			  union bpf_attr __user *uattr);
 #else
 
-struct bpf_prog;
 struct cgroup_bpf {};
 static inline int cgroup_bpf_inherit(struct cgroup *cgrp) { return 0; }
 static inline void cgroup_bpf_offline(struct cgroup *cgrp) {}
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index c9b7a876b0c8..ad4bcf1cadbb 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -310,6 +310,7 @@ enum bpf_arg_type {
 	ARG_PTR_TO_PERCPU_BTF_ID,	/* pointer to in-kernel percpu type */
 	ARG_PTR_TO_FUNC,	/* pointer to a bpf program function */
 	ARG_PTR_TO_STACK_OR_NULL,	/* pointer to stack or NULL */
+	ARG_PTR_TO_CONST_STR,	/* pointer to a null terminated read-only string */
 	__BPF_ARG_TYPE_MAX,
 };
 
@@ -930,7 +931,6 @@ struct bpf_link_primer {
 };
 
 struct bpf_struct_ops_value;
-struct btf_type;
 struct btf_member;
 
 #define BPF_STRUCT_OPS_MAX_NR_MEMBERS 64
@@ -1955,6 +1955,7 @@ extern const struct bpf_func_proto bpf_skc_to_tcp_request_sock_proto;
 extern const struct bpf_func_proto bpf_skc_to_udp6_sock_proto;
 extern const struct bpf_func_proto bpf_copy_from_user_proto;
 extern const struct bpf_func_proto bpf_snprintf_btf_proto;
+extern const struct bpf_func_proto bpf_snprintf_proto;
 extern const struct bpf_func_proto bpf_per_cpu_ptr_proto;
 extern const struct bpf_func_proto bpf_this_cpu_ptr_proto;
 extern const struct bpf_func_proto bpf_ktime_get_coarse_ns_proto;
@@ -2080,4 +2081,24 @@ int bpf_arch_text_poke(void *ip, enum bpf_text_poke_type t,
 struct btf_id_set;
 bool btf_id_set_contains(const struct btf_id_set *set, u32 id);
 
+enum bpf_printf_mod_type {
+	BPF_PRINTF_INT,
+	BPF_PRINTF_LONG,
+	BPF_PRINTF_LONG_LONG,
+};
+
+/* Workaround for getting va_list handling working with different argument type
+ * combinations generically for 32 and 64 bit archs.
+ */
+#define BPF_CAST_FMT_ARG(arg_nb, args, mod)				\
+	(mod[arg_nb] == BPF_PRINTF_LONG_LONG ||				\
+	 (mod[arg_nb] == BPF_PRINTF_LONG && __BITS_PER_LONG == 64)	\
+	  ? (u64)args[arg_nb]						\
+	  : (u32)args[arg_nb])
+
+int bpf_printf_prepare(char *fmt, u32 fmt_size, const u64 *raw_args,
+		       u64 *final_args, enum bpf_printf_mod_type *mod,
+		       u32 num_args);
+void bpf_printf_cleanup(void);
+
 #endif /* _LINUX_BPF_H */
diff --git a/include/linux/bpf_verifier.h b/include/linux/bpf_verifier.h
index 51c2ffa3d901..6023a1367853 100644
--- a/include/linux/bpf_verifier.h
+++ b/include/linux/bpf_verifier.h
@@ -487,6 +487,15 @@ static inline u64 bpf_trampoline_compute_key(const struct bpf_prog *tgt_prog,
 		return ((u64)btf_obj_id(btf) << 32) | 0x80000000 | btf_id;
 }
 
+/* unpack the IDs from the key as constructed above */
+static inline void bpf_trampoline_unpack_key(u64 key, u32 *obj_id, u32 *btf_id)
+{
+	if (obj_id)
+		*obj_id = key >> 32;
+	if (btf_id)
+		*btf_id = key & 0x7FFFFFFF;
+}
+
 int bpf_check_attach_target(struct bpf_verifier_log *log,
 			    const struct bpf_prog *prog,
 			    const struct bpf_prog *tgt_prog,
diff --git a/include/linux/skmsg.h b/include/linux/skmsg.h
index e242bf3d2b4a..aba0f0f429be 100644
--- a/include/linux/skmsg.h
+++ b/include/linux/skmsg.h
@@ -99,7 +99,8 @@ struct sk_psock {
 	void (*saved_close)(struct sock *sk, long timeout);
 	void (*saved_write_space)(struct sock *sk);
 	void (*saved_data_ready)(struct sock *sk);
-	int  (*psock_update_sk_prot)(struct sock *sk, bool restore);
+	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;
@@ -404,7 +405,7 @@ static inline void sk_psock_restore_proto(struct sock *sk,
 					  struct sk_psock *psock)
 {
 	if (psock->psock_update_sk_prot)
-		psock->psock_update_sk_prot(sk, true);
+		psock->psock_update_sk_prot(sk, psock, true);
 }
 
 static inline void sk_psock_set_state(struct sk_psock *psock,
diff --git a/include/net/sock.h b/include/net/sock.h
index cadcc12cc316..42bc5e1a627f 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -1118,6 +1118,7 @@ struct inet_hashinfo;
 struct raw_hashinfo;
 struct smc_hashinfo;
 struct module;
+struct sk_psock;
 
 /*
  * caches using SLAB_TYPESAFE_BY_RCU should let .next pointer from nulls nodes
@@ -1189,7 +1190,9 @@ struct proto {
 	void			(*rehash)(struct sock *sk);
 	int			(*get_port)(struct sock *sk, unsigned short snum);
 #ifdef CONFIG_BPF_SYSCALL
-	int			(*psock_update_sk_prot)(struct sock *sk, bool restore);
+	int			(*psock_update_sk_prot)(struct sock *sk,
+							struct sk_psock *psock,
+							bool restore);
 #endif
 
 	/* Keeping track of sockets in use */
diff --git a/include/net/tcp.h b/include/net/tcp.h
index eaea43afcc97..d05193cb0d99 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -2215,7 +2215,7 @@ struct sk_psock;
 
 #ifdef CONFIG_BPF_SYSCALL
 struct proto *tcp_bpf_get_proto(struct sock *sk, struct sk_psock *psock);
-int tcp_bpf_update_proto(struct sock *sk, bool restore);
+int tcp_bpf_update_proto(struct sock *sk, struct sk_psock *psock, bool restore);
 void tcp_bpf_clone(const struct sock *sk, struct sock *newsk);
 #endif /* CONFIG_BPF_SYSCALL */
 
diff --git a/include/net/udp.h b/include/net/udp.h
index f55aaeef7e91..360df454356c 100644
--- a/include/net/udp.h
+++ b/include/net/udp.h
@@ -543,7 +543,7 @@ static inline void udp_post_segment_fix_csum(struct sk_buff *skb)
 #ifdef CONFIG_BPF_SYSCALL
 struct sk_psock;
 struct proto *udp_bpf_get_proto(struct sock *sk, struct sk_psock *psock);
-int udp_bpf_update_proto(struct sock *sk, bool restore);
+int udp_bpf_update_proto(struct sock *sk, struct sk_psock *psock, bool restore);
 #endif
 
 #endif	/* _UDP_H */
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index 49371eba98ba..ec6d85a81744 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -312,6 +312,27 @@ union bpf_iter_link_info {
  *		*ctx_out*, *data_out* (for example, packet data), result of the
  *		execution *retval*, and *duration* of the test run.
  *
+ *		The sizes of the buffers provided as input and output
+ *		parameters *ctx_in*, *ctx_out*, *data_in*, and *data_out* must
+ *		be provided in the corresponding variables *ctx_size_in*,
+ *		*ctx_size_out*, *data_size_in*, and/or *data_size_out*. If any
+ *		of these parameters are not provided (ie set to NULL), the
+ *		corresponding size field must be zero.
+ *
+ *		Some program types have particular requirements:
+ *
+ *		**BPF_PROG_TYPE_SK_LOOKUP**
+ *			*data_in* and *data_out* must be NULL.
+ *
+ *		**BPF_PROG_TYPE_XDP**
+ *			*ctx_in* and *ctx_out* must be NULL.
+ *
+ *		**BPF_PROG_TYPE_RAW_TRACEPOINT**,
+ *		**BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE**
+ *
+ *			*ctx_out*, *data_in* and *data_out* must be NULL.
+ *			*repeat* must be zero.
+ *
  *	Return
  *		Returns zero on success. On error, -1 is returned and *errno*
  *		is set appropriately.
@@ -4061,12 +4082,20 @@ union bpf_attr {
  * 		of new data availability is sent.
  * 		If **BPF_RB_FORCE_WAKEUP** is specified in *flags*, notification
  * 		of new data availability is sent unconditionally.
+ * 		If **0** is specified in *flags*, an adaptive notification
+ * 		of new data availability is sent.
+ *
+ * 		An adaptive notification is a notification sent whenever the user-space
+ * 		process has caught up and consumed all available payloads. In case the user-space
+ * 		process is still processing a previous payload, then no notification is needed
+ * 		as it will process the newly added payload automatically.
  * 	Return
  * 		0 on success, or a negative error in case of failure.
  *
  * void *bpf_ringbuf_reserve(void *ringbuf, u64 size, u64 flags)
  * 	Description
  * 		Reserve *size* bytes of payload in a ring buffer *ringbuf*.
+ * 		*flags* must be 0.
  * 	Return
  * 		Valid pointer with *size* bytes of memory available; NULL,
  * 		otherwise.
@@ -4078,6 +4107,10 @@ union bpf_attr {
  * 		of new data availability is sent.
  * 		If **BPF_RB_FORCE_WAKEUP** is specified in *flags*, notification
  * 		of new data availability is sent unconditionally.
+ * 		If **0** is specified in *flags*, an adaptive notification
+ * 		of new data availability is sent.
+ *
+ * 		See 'bpf_ringbuf_output()' for the definition of adaptive notification.
  * 	Return
  * 		Nothing. Always succeeds.
  *
@@ -4088,6 +4121,10 @@ union bpf_attr {
  * 		of new data availability is sent.
  * 		If **BPF_RB_FORCE_WAKEUP** is specified in *flags*, notification
  * 		of new data availability is sent unconditionally.
+ * 		If **0** is specified in *flags*, an adaptive notification
+ * 		of new data availability is sent.
+ *
+ * 		See 'bpf_ringbuf_output()' for the definition of adaptive notification.
  * 	Return
  * 		Nothing. Always succeeds.
  *
@@ -4671,6 +4708,33 @@ union bpf_attr {
  *	Return
  *		The number of traversed map elements for success, **-EINVAL** for
  *		invalid **flags**.
+ *
+ * long bpf_snprintf(char *str, u32 str_size, const char *fmt, u64 *data, u32 data_len)
+ *	Description
+ *		Outputs a string into the **str** buffer of size **str_size**
+ *		based on a format string stored in a read-only map pointed by
+ *		**fmt**.
+ *
+ *		Each format specifier in **fmt** corresponds to one u64 element
+ *		in the **data** array. For strings and pointers where pointees
+ *		are accessed, only the pointer values are stored in the *data*
+ *		array. The *data_len* is the size of *data* in bytes.
+ *
+ *		Formats **%s** and **%p{i,I}{4,6}** require to read kernel
+ *		memory. Reading kernel memory may fail due to either invalid
+ *		address or valid address but requiring a major memory fault. If
+ *		reading kernel memory fails, the string for **%s** will be an
+ *		empty string, and the ip address for **%p{i,I}{4,6}** will be 0.
+ *		Not returning error to bpf program is consistent with what
+ *		**bpf_trace_printk**\ () does for now.
+ *
+ *	Return
+ *		The strictly positive length of the formatted string, including
+ *		the trailing zero character. If the return value is greater than
+ *		**str_size**, **str** contains a truncated string, guaranteed to
+ *		be zero-terminated except when **str_size** is 0.
+ *
+ *		Or **-EBUSY** if the per-CPU memory copy buffer is busy.
  */
 #define __BPF_FUNC_MAPPER(FN)		\
 	FN(unspec),			\
@@ -4838,6 +4902,7 @@ union bpf_attr {
 	FN(sock_from_file),		\
 	FN(check_mtu),			\
 	FN(for_each_map_elem),		\
+	FN(snprintf),			\
 	/* */
 
 /* integer value in 'imm' field of BPF_CALL instruction selects which helper
@@ -5379,6 +5444,8 @@ struct bpf_link_info {
 		} raw_tracepoint;
 		struct {
 			__u32 attach_type;
+			__u32 target_obj_id; /* prog_id for PROG_EXT, otherwise btf object id */
+			__u32 target_btf_id; /* BTF type id inside the object */
 		} tracing;
 		struct {
 			__u64 cgroup_id;