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

Alexei Starovoitov says:

====================
pull-request: bpf-next 2019-06-19

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

The main changes are:

1) new SO_REUSEPORT_DETACH_BPF setsocktopt, from Martin.

2) BTF based map definition, from Andrii.

3) support bpf_map_lookup_elem for xskmap, from Jonathan.

4) bounded loops and scalar precision logic in the verifier, from Alexei.
====================

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

arch/alpha/include/uapi/asm/socket.h

@@ -122,6 +122,8 @@
 #define SO_RCVTIMEO_NEW         66
 #define SO_SNDTIMEO_NEW         67
 
+#define SO_DETACH_REUSEPORT_BPF 68
+
 #if !defined(__KERNEL__)
 
 #if __BITS_PER_LONG == 64

arch/mips/include/uapi/asm/socket.h

@@ -133,6 +133,8 @@
 #define SO_RCVTIMEO_NEW         66
 #define SO_SNDTIMEO_NEW         67
 
+#define SO_DETACH_REUSEPORT_BPF 68
+
 #if !defined(__KERNEL__)
 
 #if __BITS_PER_LONG == 64

arch/parisc/include/uapi/asm/socket.h

@@ -114,6 +114,8 @@
 #define SO_RCVTIMEO_NEW         0x4040
 #define SO_SNDTIMEO_NEW         0x4041
 
+#define SO_DETACH_REUSEPORT_BPF 0x4042
+
 #if !defined(__KERNEL__)
 
 #if __BITS_PER_LONG == 64

arch/sparc/include/uapi/asm/socket.h

@@ -115,6 +115,8 @@
 #define SO_RCVTIMEO_NEW          0x0044
 #define SO_SNDTIMEO_NEW          0x0045
 
+#define SO_DETACH_REUSEPORT_BPF  0x0047
+
 #if !defined(__KERNEL__)
 
 

include/linux/bpf.h

@@ -277,6 +277,7 @@ enum bpf_reg_type {
 	PTR_TO_TCP_SOCK,	 /* reg points to struct tcp_sock */
 	PTR_TO_TCP_SOCK_OR_NULL, /* reg points to struct tcp_sock or NULL */
 	PTR_TO_TP_BUFFER,	 /* reg points to a writable raw tp's buffer */
+	PTR_TO_XDP_SOCK,	 /* reg points to struct xdp_sock */
 };
 
 /* The information passed from prog-specific *_is_valid_access
@@ -1098,6 +1099,15 @@ u32 bpf_tcp_sock_convert_ctx_access(enum bpf_access_type type,
 				    struct bpf_insn *insn_buf,
 				    struct bpf_prog *prog,
 				    u32 *target_size);
+
+bool bpf_xdp_sock_is_valid_access(int off, int size, enum bpf_access_type type,
+				  struct bpf_insn_access_aux *info);
+
+u32 bpf_xdp_sock_convert_ctx_access(enum bpf_access_type type,
+				    const struct bpf_insn *si,
+				    struct bpf_insn *insn_buf,
+				    struct bpf_prog *prog,
+				    u32 *target_size);
 #else
 static inline bool bpf_tcp_sock_is_valid_access(int off, int size,
 						enum bpf_access_type type,
@@ -1114,6 +1124,21 @@ static inline u32 bpf_tcp_sock_convert_ctx_access(enum bpf_access_type type,
 {
 	return 0;
 }
+static inline bool bpf_xdp_sock_is_valid_access(int off, int size,
+						enum bpf_access_type type,
+						struct bpf_insn_access_aux *info)
+{
+	return false;
+}
+
+static inline u32 bpf_xdp_sock_convert_ctx_access(enum bpf_access_type type,
+						  const struct bpf_insn *si,
+						  struct bpf_insn *insn_buf,
+						  struct bpf_prog *prog,
+						  u32 *target_size)
+{
+	return 0;
+}
 #endif /* CONFIG_INET */
 
 #endif /* _LINUX_BPF_H */

include/linux/bpf_verifier.h

@@ -136,6 +136,8 @@ struct bpf_reg_state {
 	 */
 	s32 subreg_def;
 	enum bpf_reg_liveness live;
+	/* if (!precise && SCALAR_VALUE) min/max/tnum don't affect safety */
+	bool precise;
 };
 
 enum bpf_stack_slot_type {
@@ -187,14 +189,77 @@ struct bpf_func_state {
 	struct bpf_stack_state *stack;
 };
 
+struct bpf_idx_pair {
+	u32 prev_idx;
+	u32 idx;
+};
+
 #define MAX_CALL_FRAMES 8
 struct bpf_verifier_state {
 	/* call stack tracking */
 	struct bpf_func_state *frame[MAX_CALL_FRAMES];
+	struct bpf_verifier_state *parent;
+	/*
+	 * 'branches' field is the number of branches left to explore:
+	 * 0 - all possible paths from this state reached bpf_exit or
+	 * were safely pruned
+	 * 1 - at least one path is being explored.
+	 * This state hasn't reached bpf_exit
+	 * 2 - at least two paths are being explored.
+	 * This state is an immediate parent of two children.
+	 * One is fallthrough branch with branches==1 and another
+	 * state is pushed into stack (to be explored later) also with
+	 * branches==1. The parent of this state has branches==1.
+	 * The verifier state tree connected via 'parent' pointer looks like:
+	 * 1
+	 * 1
+	 * 2 -> 1 (first 'if' pushed into stack)
+	 * 1
+	 * 2 -> 1 (second 'if' pushed into stack)
+	 * 1
+	 * 1
+	 * 1 bpf_exit.
+	 *
+	 * Once do_check() reaches bpf_exit, it calls update_branch_counts()
+	 * and the verifier state tree will look:
+	 * 1
+	 * 1
+	 * 2 -> 1 (first 'if' pushed into stack)
+	 * 1
+	 * 1 -> 1 (second 'if' pushed into stack)
+	 * 0
+	 * 0
+	 * 0 bpf_exit.
+	 * After pop_stack() the do_check() will resume at second 'if'.
+	 *
+	 * If is_state_visited() sees a state with branches > 0 it means
+	 * there is a loop. If such state is exactly equal to the current state
+	 * it's an infinite loop. Note states_equal() checks for states
+	 * equvalency, so two states being 'states_equal' does not mean
+	 * infinite loop. The exact comparison is provided by
+	 * states_maybe_looping() function. It's a stronger pre-check and
+	 * much faster than states_equal().
+	 *
+	 * This algorithm may not find all possible infinite loops or
+	 * loop iteration count may be too high.
+	 * In such cases BPF_COMPLEXITY_LIMIT_INSNS limit kicks in.
+	 */
+	u32 branches;
 	u32 insn_idx;
 	u32 curframe;
 	u32 active_spin_lock;
 	bool speculative;
+
+	/* first and last insn idx of this verifier state */
+	u32 first_insn_idx;
+	u32 last_insn_idx;
+	/* jmp history recorded from first to last.
+	 * backtracking is using it to go from last to first.
+	 * For most states jmp_history_cnt is [0-3].
+	 * For loops can go up to ~40.
+	 */
+	struct bpf_idx_pair *jmp_history;
+	u32 jmp_history_cnt;
 };
 
 #define bpf_get_spilled_reg(slot, frame)				\
@@ -309,7 +374,9 @@ struct bpf_verifier_env {
 	} cfg;
 	u32 subprog_cnt;
 	/* number of instructions analyzed by the verifier */
-	u32 insn_processed;
+	u32 prev_insn_processed, insn_processed;
+	/* number of jmps, calls, exits analyzed so far */
+	u32 prev_jmps_processed, jmps_processed;
 	/* total verification time */
 	u64 verification_time;
 	/* maximum number of verifier states kept in 'branching' instructions */

include/net/sock_reuseport.h

@@ -35,6 +35,8 @@ extern struct sock *reuseport_select_sock(struct sock *sk,
 					  struct sk_buff *skb,
 					  int hdr_len);
 extern int reuseport_attach_prog(struct sock *sk, struct bpf_prog *prog);
+extern int reuseport_detach_prog(struct sock *sk);
+
 int reuseport_get_id(struct sock_reuseport *reuse);
 
 #endif  /* _SOCK_REUSEPORT_H */

include/net/xdp_sock.h

@@ -58,11 +58,11 @@ struct xdp_sock {
 	struct xdp_umem *umem;
 	struct list_head flush_node;
 	u16 queue_id;
-	struct xsk_queue *tx ____cacheline_aligned_in_smp;
-	struct list_head list;
 	bool zc;
 	/* Protects multiple processes in the control path */
 	struct mutex mutex;
+	struct xsk_queue *tx ____cacheline_aligned_in_smp;
+	struct list_head list;
 	/* Mutual exclusion of NAPI TX thread and sendmsg error paths
 	 * in the SKB destructor callback.
 	 */

include/uapi/asm-generic/socket.h

@@ -117,6 +117,8 @@
 #define SO_RCVTIMEO_NEW         66
 #define SO_SNDTIMEO_NEW         67
 
+#define SO_DETACH_REUSEPORT_BPF 68
+
 #if !defined(__KERNEL__)
 
 #if __BITS_PER_LONG == 64 || (defined(__x86_64__) && defined(__ILP32__))

include/uapi/linux/bpf.h

@@ -3085,6 +3085,10 @@ struct bpf_sock_tuple {
 	};
 };
 
+struct bpf_xdp_sock {
+	__u32 queue_id;
+};
+
 #define XDP_PACKET_HEADROOM 256
 
 /* User return codes for XDP prog type.
@@ -3245,6 +3249,7 @@ struct bpf_sock_addr {
 	__u32 msg_src_ip6[4];	/* Allows 1,2,4-byte read an 4-byte write.
 				 * Stored in network byte order.
 				 */
+	__bpf_md_ptr(struct bpf_sock *, sk);
 };
 
 /* User bpf_sock_ops struct to access socket values and specify request ops
@@ -3296,6 +3301,7 @@ struct bpf_sock_ops {
 	__u32 sk_txhash;
 	__u64 bytes_received;
 	__u64 bytes_acked;
+	__bpf_md_ptr(struct bpf_sock *, sk);
 };
 
 /* Definitions for bpf_sock_ops_cb_flags */

kernel/bpf/Makefile

@@ -1,5 +1,6 @@
 # SPDX-License-Identifier: GPL-2.0
 obj-y := core.o
+CFLAGS_core.o += $(call cc-disable-warning, override-init)
 
 obj-$(CONFIG_BPF_SYSCALL) += syscall.o verifier.o inode.o helpers.o tnum.o
 obj-$(CONFIG_BPF_SYSCALL) += hashtab.o arraymap.o percpu_freelist.o bpf_lru_list.o lpm_trie.o map_in_map.o

kernel/bpf/devmap.c

@@ -80,8 +80,8 @@ static u64 dev_map_bitmap_size(const union bpf_attr *attr)
 static struct bpf_map *dev_map_alloc(union bpf_attr *attr)
 {
 	struct bpf_dtab *dtab;
-	int err = -EINVAL;
 	u64 cost;
+	int err;
 
 	if (!capable(CAP_NET_ADMIN))
 		return ERR_PTR(-EPERM);