v4.19.13 snapshot.
diff --git a/include/linux/bpf_verifier.h b/include/linux/bpf_verifier.h
new file mode 100644
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--- /dev/null
+++ b/include/linux/bpf_verifier.h
@@ -0,0 +1,223 @@
+/* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ */
+#ifndef _LINUX_BPF_VERIFIER_H
+#define _LINUX_BPF_VERIFIER_H 1
+
+#include <linux/bpf.h> /* for enum bpf_reg_type */
+#include <linux/filter.h> /* for MAX_BPF_STACK */
+#include <linux/tnum.h>
+
+/* Maximum variable offset umax_value permitted when resolving memory accesses.
+ * In practice this is far bigger than any realistic pointer offset; this limit
+ * ensures that umax_value + (int)off + (int)size cannot overflow a u64.
+ */
+#define BPF_MAX_VAR_OFF (1 << 29)
+/* Maximum variable size permitted for ARG_CONST_SIZE[_OR_ZERO]. This ensures
+ * that converting umax_value to int cannot overflow.
+ */
+#define BPF_MAX_VAR_SIZ (1 << 29)
+
+/* Liveness marks, used for registers and spilled-regs (in stack slots).
+ * Read marks propagate upwards until they find a write mark; they record that
+ * "one of this state's descendants read this reg" (and therefore the reg is
+ * relevant for states_equal() checks).
+ * Write marks collect downwards and do not propagate; they record that "the
+ * straight-line code that reached this state (from its parent) wrote this reg"
+ * (and therefore that reads propagated from this state or its descendants
+ * should not propagate to its parent).
+ * A state with a write mark can receive read marks; it just won't propagate
+ * them to its parent, since the write mark is a property, not of the state,
+ * but of the link between it and its parent. See mark_reg_read() and
+ * mark_stack_slot_read() in kernel/bpf/verifier.c.
+ */
+enum bpf_reg_liveness {
+ REG_LIVE_NONE = 0, /* reg hasn't been read or written this branch */
+ REG_LIVE_READ, /* reg was read, so we're sensitive to initial value */
+ REG_LIVE_WRITTEN, /* reg was written first, screening off later reads */
+};
+
+struct bpf_reg_state {
+ enum bpf_reg_type type;
+ union {
+ /* valid when type == PTR_TO_PACKET */
+ u16 range;
+
+ /* valid when type == CONST_PTR_TO_MAP | PTR_TO_MAP_VALUE |
+ * PTR_TO_MAP_VALUE_OR_NULL
+ */
+ struct bpf_map *map_ptr;
+
+ /* Max size from any of the above. */
+ unsigned long raw;
+ };
+ /* Fixed part of pointer offset, pointer types only */
+ s32 off;
+ /* For PTR_TO_PACKET, used to find other pointers with the same variable
+ * offset, so they can share range knowledge.
+ * For PTR_TO_MAP_VALUE_OR_NULL this is used to share which map value we
+ * came from, when one is tested for != NULL.
+ */
+ u32 id;
+ /* Ordering of fields matters. See states_equal() */
+ /* For scalar types (SCALAR_VALUE), this represents our knowledge of
+ * the actual value.
+ * For pointer types, this represents the variable part of the offset
+ * from the pointed-to object, and is shared with all bpf_reg_states
+ * with the same id as us.
+ */
+ struct tnum var_off;
+ /* Used to determine if any memory access using this register will
+ * result in a bad access.
+ * These refer to the same value as var_off, not necessarily the actual
+ * contents of the register.
+ */
+ s64 smin_value; /* minimum possible (s64)value */
+ s64 smax_value; /* maximum possible (s64)value */
+ u64 umin_value; /* minimum possible (u64)value */
+ u64 umax_value; /* maximum possible (u64)value */
+ /* Inside the callee two registers can be both PTR_TO_STACK like
+ * R1=fp-8 and R2=fp-8, but one of them points to this function stack
+ * while another to the caller's stack. To differentiate them 'frameno'
+ * is used which is an index in bpf_verifier_state->frame[] array
+ * pointing to bpf_func_state.
+ * This field must be second to last, for states_equal() reasons.
+ */
+ u32 frameno;
+ /* This field must be last, for states_equal() reasons. */
+ enum bpf_reg_liveness live;
+};
+
+enum bpf_stack_slot_type {
+ STACK_INVALID, /* nothing was stored in this stack slot */
+ STACK_SPILL, /* register spilled into stack */
+ STACK_MISC, /* BPF program wrote some data into this slot */
+ STACK_ZERO, /* BPF program wrote constant zero */
+};
+
+#define BPF_REG_SIZE 8 /* size of eBPF register in bytes */
+
+struct bpf_stack_state {
+ struct bpf_reg_state spilled_ptr;
+ u8 slot_type[BPF_REG_SIZE];
+};
+
+/* state of the program:
+ * type of all registers and stack info
+ */
+struct bpf_func_state {
+ struct bpf_reg_state regs[MAX_BPF_REG];
+ struct bpf_verifier_state *parent;
+ /* index of call instruction that called into this func */
+ int callsite;
+ /* stack frame number of this function state from pov of
+ * enclosing bpf_verifier_state.
+ * 0 = main function, 1 = first callee.
+ */
+ u32 frameno;
+ /* subprog number == index within subprog_stack_depth
+ * zero == main subprog
+ */
+ u32 subprogno;
+
+ /* should be second to last. See copy_func_state() */
+ int allocated_stack;
+ struct bpf_stack_state *stack;
+};
+
+#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;
+ u32 curframe;
+};
+
+/* linked list of verifier states used to prune search */
+struct bpf_verifier_state_list {
+ struct bpf_verifier_state state;
+ struct bpf_verifier_state_list *next;
+};
+
+struct bpf_insn_aux_data {
+ union {
+ enum bpf_reg_type ptr_type; /* pointer type for load/store insns */
+ unsigned long map_state; /* pointer/poison value for maps */
+ s32 call_imm; /* saved imm field of call insn */
+ };
+ int ctx_field_size; /* the ctx field size for load insn, maybe 0 */
+ int sanitize_stack_off; /* stack slot to be cleared */
+ bool seen; /* this insn was processed by the verifier */
+};
+
+#define MAX_USED_MAPS 64 /* max number of maps accessed by one eBPF program */
+
+#define BPF_VERIFIER_TMP_LOG_SIZE 1024
+
+struct bpf_verifier_log {
+ u32 level;
+ char kbuf[BPF_VERIFIER_TMP_LOG_SIZE];
+ char __user *ubuf;
+ u32 len_used;
+ u32 len_total;
+};
+
+static inline bool bpf_verifier_log_full(const struct bpf_verifier_log *log)
+{
+ return log->len_used >= log->len_total - 1;
+}
+
+static inline bool bpf_verifier_log_needed(const struct bpf_verifier_log *log)
+{
+ return log->level && log->ubuf && !bpf_verifier_log_full(log);
+}
+
+#define BPF_MAX_SUBPROGS 256
+
+struct bpf_subprog_info {
+ u32 start; /* insn idx of function entry point */
+ u16 stack_depth; /* max. stack depth used by this function */
+};
+
+/* single container for all structs
+ * one verifier_env per bpf_check() call
+ */
+struct bpf_verifier_env {
+ struct bpf_prog *prog; /* eBPF program being verified */
+ const struct bpf_verifier_ops *ops;
+ struct bpf_verifier_stack_elem *head; /* stack of verifier states to be processed */
+ int stack_size; /* number of states to be processed */
+ bool strict_alignment; /* perform strict pointer alignment checks */
+ struct bpf_verifier_state *cur_state; /* current verifier state */
+ struct bpf_verifier_state_list **explored_states; /* search pruning optimization */
+ struct bpf_map *used_maps[MAX_USED_MAPS]; /* array of map's used by eBPF program */
+ u32 used_map_cnt; /* number of used maps */
+ u32 id_gen; /* used to generate unique reg IDs */
+ bool allow_ptr_leaks;
+ bool seen_direct_write;
+ struct bpf_insn_aux_data *insn_aux_data; /* array of per-insn state */
+ struct bpf_verifier_log log;
+ struct bpf_subprog_info subprog_info[BPF_MAX_SUBPROGS + 1];
+ u32 subprog_cnt;
+};
+
+__printf(2, 0) void bpf_verifier_vlog(struct bpf_verifier_log *log,
+ const char *fmt, va_list args);
+__printf(2, 3) void bpf_verifier_log_write(struct bpf_verifier_env *env,
+ const char *fmt, ...);
+
+static inline struct bpf_reg_state *cur_regs(struct bpf_verifier_env *env)
+{
+ struct bpf_verifier_state *cur = env->cur_state;
+
+ return cur->frame[cur->curframe]->regs;
+}
+
+int bpf_prog_offload_verifier_prep(struct bpf_verifier_env *env);
+int bpf_prog_offload_verify_insn(struct bpf_verifier_env *env,
+ int insn_idx, int prev_insn_idx);
+
+#endif /* _LINUX_BPF_VERIFIER_H */