/* SPDX-License-Identifier: GPL-2.0-only */
/* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
 */
#ifndef _LINUX_BPF_VERIFIER_H
#define _LINUX_BPF_VERIFIER_H 1

#include <linux/bpf.h> /* for enum bpf_reg_type */
#include <linux/btf.h> /* for struct btf and btf_id() */
#include <linux/filter.h> /* for MAX_BPF_STACK */
#include <linux/tnum.h>
#include <linux/cnum.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)
/* size of tmp_str_buf in bpf_verifier.
 * we need at least 306 bytes to fit full stack mask representation
 * (in the "-8,-16,...,-512" form)
 */
#define TMP_STR_BUF_LEN 320
/* Patch buffer size */
#define INSN_BUF_SIZE 32

#define ITER_PREFIX "bpf_iter_"

enum bpf_iter_state {
        BPF_ITER_STATE_INVALID, /* for non-first slot */
        BPF_ITER_STATE_ACTIVE,
        BPF_ITER_STATE_DRAINED,
};

struct bpf_reg_state {
        /* Ordering of fields matters.  See states_equal() */
        enum bpf_reg_type type;
        /*
         * Constant delta between "linked" scalars with the same ID.
         */
        s32 delta;
        union {
                /* valid when type == PTR_TO_PACKET */
                int range;

                /* valid when type == CONST_PTR_TO_MAP | PTR_TO_MAP_VALUE |
                 *   PTR_TO_MAP_VALUE_OR_NULL
                 */
                struct {
                        struct bpf_map *map_ptr;
                        /* To distinguish map lookups from outer map
                         * the map_uid is non-zero for registers
                         * pointing to inner maps.
                         */
                        u32 map_uid;
                };

                /* for PTR_TO_BTF_ID */
                struct {
                        struct btf *btf;
                        u32 btf_id;
                };

                struct { /* for PTR_TO_MEM | PTR_TO_MEM_OR_NULL */
                        u32 mem_size;
                };

                /* For dynptr stack slots */
                struct {
                        enum bpf_dynptr_type type;
                        /* A dynptr is 16 bytes so it takes up 2 stack slots.
                         * We need to track which slot is the first slot
                         * to protect against cases where the user may try to
                         * pass in an address starting at the second slot of the
                         * dynptr.
                         */
                        bool first_slot;
                } dynptr;

                /* For bpf_iter stack slots */
                struct {
                        /* BTF container and BTF type ID describing
                         * struct bpf_iter_<type> of an iterator state
                         */
                        struct btf *btf;
                        u32 btf_id;
                        /* packing following two fields to fit iter state into 16 bytes */
                        enum bpf_iter_state state:2;
                        int depth:30;
                } iter;

                /* For irq stack slots */
                struct {
                        enum {
                                IRQ_NATIVE_KFUNC,
                                IRQ_LOCK_KFUNC,
                        } kfunc_class;
                } irq;

                /* Max size from any of the above. */
                struct {
                        unsigned long raw1;
                        unsigned long raw2;
                } raw;

                u32 subprogno; /* for PTR_TO_FUNC */
        };
        /* 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.
         */
        struct cnum64 r64; /* 64-bit range as circular number */
        struct cnum32 r32; /* 32-bit range as circular number */
        /* 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.
         * For PTR_TO_MEM_OR_NULL this is used to identify memory allocation
         * for the purpose of tracking that it's freed.
         * For PTR_TO_SOCKET this is used to share which pointers retain the
         * same reference to the socket, to determine proper reference freeing.
         * For stack slots that are dynptrs, this is used to track references to
         * the dynptr to determine proper reference freeing.
         * Similarly to dynptrs, we use ID to track "belonging" of a reference
         * to a specific instance of bpf_iter.
         */
        /*
         * Upper bit of ID is used to remember relationship between "linked"
         * registers. Example:
         * r1 = r2;    both will have r1->id == r2->id == N
         * r1 += 10;   r1->id == N | BPF_ADD_CONST and r1->delta == 10
         * r3 = r2;    both will have r3->id == r2->id == N
         * w3 += 10;   r3->id == N | BPF_ADD_CONST32 and r3->delta == 10
         */
#define BPF_ADD_CONST64 (1U << 31)
#define BPF_ADD_CONST32 (1U << 30)
#define BPF_ADD_CONST (BPF_ADD_CONST64 | BPF_ADD_CONST32)
        u32 id;
        /*
         * Tracks the parent object this register was derived from.
         * Used for cascading invalidation: when the parent object is
         * released or invalidated, all registers with matching parent_id
         * are also invalidated. For example, a slice from bpf_dynptr_data()
         * gets parent_id set to the dynptr's id.
         */
        u32 parent_id;
        /* 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.
         */
        u32 frameno;
        /* Tracks subreg definition. The stored value is the insn_idx of the
         * writing insn. This is safe because subreg_def is used before any insn
         * patching which only happens after main verification finished.
         */
        s32 subreg_def;
        /* if (!precise && SCALAR_VALUE) min/max/tnum don't affect safety */
        bool precise;
};

static inline s64 reg_smin(const struct bpf_reg_state *reg)
{
        return cnum64_smin(reg->r64);
}

static inline s64 reg_smax(const struct bpf_reg_state *reg)
{
        return cnum64_smax(reg->r64);
}

static inline u64 reg_umin(const struct bpf_reg_state *reg)
{
        return cnum64_umin(reg->r64);
}

static inline u64 reg_umax(const struct bpf_reg_state *reg)
{
        return cnum64_umax(reg->r64);
}

static inline s32 reg_s32_min(const struct bpf_reg_state *reg)
{
        return cnum32_smin(reg->r32);
}

static inline s32 reg_s32_max(const struct bpf_reg_state *reg)
{
        return cnum32_smax(reg->r32);
}

static inline u32 reg_u32_min(const struct bpf_reg_state *reg)
{
        return cnum32_umin(reg->r32);
}

static inline u32 reg_u32_max(const struct bpf_reg_state *reg)
{
        return cnum32_umax(reg->r32);
}

static inline void reg_set_srange32(struct bpf_reg_state *reg, s32 smin, s32 smax)
{
        reg->r32 = cnum32_from_srange(smin, smax);
}

static inline void reg_set_urange32(struct bpf_reg_state *reg, u32 umin, u32 umax)
{
        reg->r32 = cnum32_from_urange(umin, umax);
}

static inline void reg_set_srange64(struct bpf_reg_state *reg, s64 smin, s64 smax)
{
        reg->r64 = cnum64_from_srange(smin, smax);
}

static inline void reg_set_urange64(struct bpf_reg_state *reg, u64 umin, u64 umax)
{
        reg->r64 = cnum64_from_urange(umin, umax);
}

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 */
        /* A dynptr is stored in this stack slot. The type of dynptr
         * is stored in bpf_stack_state->spilled_ptr.dynptr.type
         */
        STACK_DYNPTR,
        STACK_ITER,
        STACK_IRQ_FLAG,
        STACK_POISON,
};

#define BPF_REG_SIZE 8  /* size of eBPF register in bytes */

/* 4-byte stack slot granularity for liveness analysis */
#define BPF_HALF_REG_SIZE       4
#define STACK_SLOT_SZ           4
#define STACK_SLOTS             (MAX_BPF_STACK / BPF_HALF_REG_SIZE)     /* 128 */

typedef struct {
        u64 v[2];
} spis_t;

#define SPIS_ZERO       ((spis_t){})
#define SPIS_ALL        ((spis_t){{ U64_MAX, U64_MAX }})

static inline bool spis_is_zero(spis_t s)
{
        return s.v[0] == 0 && s.v[1] == 0;
}

static inline bool spis_equal(spis_t a, spis_t b)
{
        return a.v[0] == b.v[0] && a.v[1] == b.v[1];
}

static inline spis_t spis_or(spis_t a, spis_t b)
{
        return (spis_t){{ a.v[0] | b.v[0], a.v[1] | b.v[1] }};
}

static inline spis_t spis_and(spis_t a, spis_t b)
{
        return (spis_t){{ a.v[0] & b.v[0], a.v[1] & b.v[1] }};
}

static inline spis_t spis_not(spis_t s)
{
        return (spis_t){{ ~s.v[0], ~s.v[1] }};
}

static inline bool spis_test_bit(spis_t s, u32 slot)
{
        return s.v[slot / 64] & BIT_ULL(slot % 64);
}

static inline void spis_or_range(spis_t *mask, u32 lo, u32 hi)
{
        u32 w;

        for (w = lo; w <= hi && w < STACK_SLOTS; w++)
                mask->v[w / 64] |= BIT_ULL(w % 64);
}

#define BPF_REGMASK_ARGS ((1 << BPF_REG_1) | (1 << BPF_REG_2) | \
                          (1 << BPF_REG_3) | (1 << BPF_REG_4) | \
                          (1 << BPF_REG_5))

#define BPF_MAIN_FUNC (-1)

#define BPF_DYNPTR_SIZE         sizeof(struct bpf_dynptr_kern)
#define BPF_DYNPTR_NR_SLOTS             (BPF_DYNPTR_SIZE / BPF_REG_SIZE)

struct bpf_stack_state {
        struct bpf_reg_state spilled_ptr;
        u8 slot_type[BPF_REG_SIZE];
};

struct bpf_reference_state {
        /* Each reference object has a type. Ensure REF_TYPE_PTR is zero to
         * default to pointer reference on zero initialization of a state.
         */
        enum ref_state_type {
                REF_TYPE_PTR            = (1 << 1),
                REF_TYPE_IRQ            = (1 << 2),
                REF_TYPE_LOCK           = (1 << 3),
                REF_TYPE_RES_LOCK       = (1 << 4),
                REF_TYPE_RES_LOCK_IRQ   = (1 << 5),
                REF_TYPE_LOCK_MASK      = REF_TYPE_LOCK | REF_TYPE_RES_LOCK | REF_TYPE_RES_LOCK_IRQ,
        } type;
        /* Track each reference created with a unique id, even if the same
         * instruction creates the reference multiple times (eg, via CALL).
         */
        int id;
        /* Instruction where the allocation of this reference occurred. This
         * is used purely to inform the user of a reference leak.
         */
        int insn_idx;
        union {
                /* For REF_TYPE_PTR */
                int parent_id;
                /* Use to keep track of the source object of a lock, to ensure
                 * it matches on unlock.
                 */
                void *ptr;
        };
};

struct bpf_retval_range {
        s32 minval;
        s32 maxval;
        bool return_32bit;
};

/* state of the program:
 * type of all registers and stack info
 */
struct bpf_func_state {
        struct bpf_reg_state regs[MAX_BPF_REG];
        /* 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_info
         * zero == main subprog
         */
        u32 subprogno;
        /* Every bpf_timer_start will increment async_entry_cnt.
         * It's used to distinguish:
         * void foo(void) { for(;;); }
         * void foo(void) { bpf_timer_set_callback(,foo); }
         */
        u32 async_entry_cnt;
        struct bpf_retval_range callback_ret_range;
        bool in_callback_fn;
        bool in_async_callback_fn;
        bool in_exception_callback_fn;
        bool no_stack_arg_load;
        /* For callback calling functions that limit number of possible
         * callback executions (e.g. bpf_loop) keeps track of current
         * simulated iteration number.
         * Value in frame N refers to number of times callback with frame
         * N+1 was simulated, e.g. for the following call:
         *
         *   bpf_loop(..., fn, ...); | suppose current frame is N
         *                           | fn would be simulated in frame N+1
         *                           | number of simulations is tracked in frame N
         */
        u32 callback_depth;

        /* The following fields should be last. See copy_func_state() */
        /* The state of the stack. Each element of the array describes BPF_REG_SIZE
         * (i.e. 8) bytes worth of stack memory.
         * stack[0] represents bytes [*(r10-8)..*(r10-1)]
         * stack[1] represents bytes [*(r10-16)..*(r10-9)]
         * ...
         * stack[allocated_stack/8 - 1] represents [*(r10-allocated_stack)..*(r10-allocated_stack+7)]
         */
        struct bpf_stack_state *stack;
        /* Size of the current stack, in bytes. The stack state is tracked below, in
         * `stack`. allocated_stack is always a multiple of BPF_REG_SIZE.
         */
        int allocated_stack;

        u16 out_stack_arg_cnt; /* Number of outgoing on-stack argument slots */
        struct bpf_reg_state *stack_arg_regs; /* Outgoing on-stack arguments */
};

#define MAX_CALL_FRAMES 16

/* instruction history flags, used in bpf_jmp_history_entry.flags field.
 * Frame number and SPI are stored in dedicated fields of bpf_jmp_history_entry.
 */
enum {
        INSN_F_STACK_ACCESS = BIT(0),

        INSN_F_DST_REG_STACK = BIT(1), /* dst_reg is PTR_TO_STACK */
        INSN_F_SRC_REG_STACK = BIT(2), /* src_reg is PTR_TO_STACK */

        INSN_F_STACK_ARG_ACCESS = BIT(3),
};

struct bpf_jmp_history_entry {
        /* insn idx can't be bigger than 1 million */
        u32 idx : 20;
        u32 frame : 4;  /* stack access frame number */
        u32 spi : 6;    /* stack slot index (0..63) */
        u32 : 2;
        u32 prev_idx : 20;
        /* special INSN_F_xxx flags */
        u32 flags : 4;
        u32 : 8;
        /*
         * additional registers that need precision tracking when this
         * jump is backtracked, vector of five 11-bit records
         */
        u64 linked_regs;
};

static_assert(MAX_CALL_FRAMES <= (1 << 4));
static_assert(MAX_BPF_STACK / 8 <= (1 << 6));

/* Maximum number of bpf_reg_state objects that can exist at once */
#define MAX_STACK_ARG_SLOTS (MAX_BPF_FUNC_ARGS - MAX_BPF_FUNC_REG_ARGS)
#define BPF_ID_MAP_SIZE ((MAX_BPF_REG + MAX_BPF_STACK / BPF_REG_SIZE + \
                          MAX_STACK_ARG_SLOTS) * MAX_CALL_FRAMES)
struct bpf_verifier_state {
        /* call stack tracking */
        struct bpf_func_state *frame[MAX_CALL_FRAMES];
        struct bpf_verifier_state *parent;
        /* Acquired reference states */
        struct bpf_reference_state *refs;
        /*
         * '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
         * equivalency, 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 acquired_refs;
        u32 active_locks;
        u32 active_preempt_locks;
        u32 active_irq_id;
        u32 active_lock_id;
        void *active_lock_ptr;
        u32 active_rcu_locks;

        bool speculative;
        bool in_sleepable;

        /* first and last insn idx of this verifier state */
        u32 first_insn_idx;
        u32 last_insn_idx;
        /* if this state is a backedge state then equal_state
         * records cached state to which this state is equal.
         */
        struct bpf_verifier_state *equal_state;
        /* 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_jmp_history_entry *jmp_history;
        u32 jmp_history_cnt;
        u32 dfs_depth;
        u32 callback_unroll_depth;
        u32 may_goto_depth;
};

static inline struct bpf_reg_state *
bpf_get_spilled_reg(int slot, struct bpf_func_state *frame, u32 mask)
{
        if (slot < frame->allocated_stack / BPF_REG_SIZE &&
            (1 << frame->stack[slot].slot_type[BPF_REG_SIZE - 1]) & mask)
                return &frame->stack[slot].spilled_ptr;
        return NULL;
}

static inline struct bpf_reg_state *
bpf_get_spilled_stack_arg(int slot, struct bpf_func_state *frame)
{
        if (slot < frame->out_stack_arg_cnt &&
            frame->stack_arg_regs[slot].type != NOT_INIT)
                return &frame->stack_arg_regs[slot];
        return NULL;
}

/* Iterate over 'frame', setting 'reg' to either NULL or a spilled register. */
#define bpf_for_each_spilled_reg(iter, frame, reg, mask)                        \
        for (iter = 0, reg = bpf_get_spilled_reg(iter, frame, mask);            \
             iter < frame->allocated_stack / BPF_REG_SIZE;              \
             iter++, reg = bpf_get_spilled_reg(iter, frame, mask))

/* Iterate over 'frame', setting 'reg' to either NULL or a spilled stack arg. */
#define bpf_for_each_spilled_stack_arg(iter, frame, reg)               \
        for (iter = 0, reg = bpf_get_spilled_stack_arg(iter, frame);   \
             iter < frame->out_stack_arg_cnt;                          \
             iter++, reg = bpf_get_spilled_stack_arg(iter, frame))

#define bpf_for_each_reg_in_vstate_mask(__vst, __state, __reg, __stack, __mask, __expr)   \
        ({                                                               \
                struct bpf_verifier_state *___vstate = __vst;            \
                int ___i, ___j;                                          \
                for (___i = 0; ___i <= ___vstate->curframe; ___i++) {    \
                        struct bpf_reg_state *___regs;                   \
                        __state = ___vstate->frame[___i];                \
                        ___regs = __state->regs;                         \
                        __stack = NULL;                                  \
                        for (___j = 0; ___j < MAX_BPF_REG; ___j++) {     \
                                __reg = &___regs[___j];                  \
                                (void)(__expr);                          \
                        }                                                \
                        bpf_for_each_spilled_reg(___j, __state, __reg, __mask) { \
                                if (!__reg)                              \
                                        continue;                        \
                                __stack = &__state->stack[___j];         \
                                (void)(__expr);                          \
                        }                                                \
                        __stack = NULL;                                  \
                        bpf_for_each_spilled_stack_arg(___j, __state, __reg) { \
                                if (!__reg)                              \
                                        continue;                        \
                                (void)(__expr);                          \
                        }                                                \
                }                                                        \
                (void)__stack;                                           \
        })

/* Invoke __expr over regsiters in __vst, setting __state and __reg */
#define bpf_for_each_reg_in_vstate(__vst, __state, __reg, __expr)               \
        ({                                                                      \
                struct bpf_stack_state * ___stack;                              \
                (void)___stack;                                                 \
                bpf_for_each_reg_in_vstate_mask(__vst, __state, __reg, ___stack,\
                                                1 << STACK_SPILL, __expr);      \
        })

/* linked list of verifier states used to prune search */
struct bpf_verifier_state_list {
        struct bpf_verifier_state state;
        struct list_head node;
        u32 miss_cnt;
        u32 hit_cnt:31;
        u32 in_free_list:1;
};

struct bpf_loop_inline_state {
        unsigned int initialized:1; /* set to true upon first entry */
        unsigned int fit_for_inline:1; /* true if callback function is the same
                                        * at each call and flags are always zero
                                        */
        u32 callback_subprogno; /* valid when fit_for_inline is true */
};

/* pointer and state for maps */
struct bpf_map_ptr_state {
        struct bpf_map *map_ptr;
        bool poison;
        bool unpriv;
};

/* Possible states for alu_state member. */
#define BPF_ALU_SANITIZE_SRC            (1U << 0)
#define BPF_ALU_SANITIZE_DST            (1U << 1)
#define BPF_ALU_NEG_VALUE               (1U << 2)
#define BPF_ALU_NON_POINTER             (1U << 3)
#define BPF_ALU_IMMEDIATE               (1U << 4)
#define BPF_ALU_SANITIZE                (BPF_ALU_SANITIZE_SRC | \
                                         BPF_ALU_SANITIZE_DST)

/*
 * An array of BPF instructions.
 * Primary usage: return value of bpf_insn_successors.
 */
struct bpf_iarray {
        int cnt;
        u32 items[];
};

struct bpf_insn_aux_data {
        union {
                enum bpf_reg_type ptr_type;     /* pointer type for load/store insns */
                struct bpf_map_ptr_state map_ptr_state;
                s32 call_imm;                   /* saved imm field of call insn */
                u32 alu_limit;                  /* limit for add/sub register with pointer */
                struct {
                        u32 map_index;          /* index into used_maps[] */
                        u32 map_off;            /* offset from value base address */
                };
                struct {
                        enum bpf_reg_type reg_type;     /* type of pseudo_btf_id */
                        union {
                                struct {
                                        struct btf *btf;
                                        u32 btf_id;     /* btf_id for struct typed var */
                                };
                                u32 mem_size;   /* mem_size for non-struct typed var */
                        };
                } btf_var;
                /* if instruction is a call to bpf_loop this field tracks
                 * the state of the relevant registers to make decision about inlining
                 */
                struct bpf_loop_inline_state loop_inline_state;
        };
        union {
                /* remember the size of type passed to bpf_obj_new to rewrite R1 */
                u64 obj_new_size;
                /* remember the offset of node field within type to rewrite */
                u64 insert_off;
        };
        struct bpf_iarray *jt;  /* jump table for gotox or bpf_tailcall call instruction */
        struct btf_struct_meta *kptr_struct_meta;
        u64 map_key_state; /* constant (32 bit) key tracking for maps */
        int ctx_field_size; /* the ctx field size for load insn, maybe 0 */
        u32 seen; /* this insn was processed by the verifier at env->pass_cnt */
        bool nospec; /* do not execute this instruction speculatively */
        bool nospec_result; /* result is unsafe under speculation, nospec must follow */
        bool zext_dst; /* this insn zero extends dst reg */
        bool needs_zext; /* alu op needs to clear upper bits */
        bool non_sleepable; /* helper/kfunc may be called from non-sleepable context */
        bool is_iter_next; /* bpf_iter_<type>_next() kfunc call */
        bool call_with_percpu_alloc_ptr; /* {this,per}_cpu_ptr() with prog percpu alloc */
        u8 alu_state; /* used in combination with alu_limit */
        /* true if STX or LDX instruction is a part of a spill/fill
         * pattern for a bpf_fastcall call.
         */
        u8 fastcall_pattern:1;
        /* for CALL instructions, a number of spill/fill pairs in the
         * bpf_fastcall pattern.
         */
        u8 fastcall_spills_num:3;
        u8 arg_prog:4;

        /* below fields are initialized once */
        unsigned int orig_idx; /* original instruction index */
        u32 jmp_point:1;
        u32 prune_point:1;
        /* ensure we check state equivalence and save state checkpoint and
         * this instruction, regardless of any heuristics
         */
        u32 force_checkpoint:1;
        /* true if instruction is a call to a helper function that
         * accepts callback function as a parameter.
         */
        u32 calls_callback:1;
        u32 indirect_target:1; /* if it is an indirect jump target */
        /*
         * CFG strongly connected component this instruction belongs to,
         * zero if it is a singleton SCC.
         */
        u32 scc;
        /* registers alive before this instruction. */
        u16 live_regs_before;
        /*
         * Bitmask of R0-R9 that hold known values at this instruction.
         * const_reg_mask: scalar constants that fit in 32 bits.
         * const_reg_map_mask: map pointers, val is map_index into used_maps[].
         * const_reg_subprog_mask: subprog pointers, val is subprog number.
         * const_reg_vals[i] holds the 32-bit value for register i.
         * Populated by compute_const_regs() pre-pass.
         */
        u16 const_reg_mask;
        u16 const_reg_map_mask;
        u16 const_reg_subprog_mask;
        u32 const_reg_vals[10];
};

#define MAX_USED_MAPS 64 /* max number of maps accessed by one eBPF program */
#define MAX_USED_BTFS 64 /* max number of BTFs accessed by one BPF program */

#define BPF_VERIFIER_TMP_LOG_SIZE       1024

struct bpf_verifier_log {
        /* Logical start and end positions of a "log window" of the verifier log.
         * start_pos == 0 means we haven't truncated anything.
         * Once truncation starts to happen, start_pos + len_total == end_pos,
         * except during log reset situations, in which (end_pos - start_pos)
         * might get smaller than len_total (see bpf_vlog_reset()).
         * Generally, (end_pos - start_pos) gives number of useful data in
         * user log buffer.
         */
        u64 start_pos;
        u64 end_pos;
        char __user *ubuf;
        u32 level;
        u32 len_total;
        u32 len_max;
        char kbuf[BPF_VERIFIER_TMP_LOG_SIZE];
};

#define BPF_LOG_LEVEL1  1
#define BPF_LOG_LEVEL2  2
#define BPF_LOG_STATS   4
#define BPF_LOG_FIXED   8
#define BPF_LOG_LEVEL   (BPF_LOG_LEVEL1 | BPF_LOG_LEVEL2)
#define BPF_LOG_MASK    (BPF_LOG_LEVEL | BPF_LOG_STATS | BPF_LOG_FIXED)
#define BPF_LOG_KERNEL  (BPF_LOG_MASK + 1) /* kernel internal flag */
#define BPF_LOG_MIN_ALIGNMENT 8U
#define BPF_LOG_ALIGNMENT 40U

static inline bool bpf_verifier_log_needed(const struct bpf_verifier_log *log)
{
        return log && log->level;
}

struct bpf_log_attr {
        char __user *ubuf;
        u32 size;
        u32 level;
        u32 offsetof_true_size;
        bpfptr_t uattr;
};

int bpf_log_attr_init(struct bpf_log_attr *log, u64 log_buf, u32 log_size, u32 log_level,
                      u32 offsetof_log_true_size, bpfptr_t uattr, struct bpf_common_attr *common,
                      bpfptr_t uattr_common, u32 size_common);
struct bpf_verifier_log *bpf_log_attr_create_vlog(struct bpf_log_attr *attr_log,
                                                  struct bpf_common_attr *common, bpfptr_t uattr,
                                                  u32 size);
int bpf_log_attr_finalize(struct bpf_log_attr *attr, struct bpf_verifier_log *log);

#define BPF_MAX_SUBPROGS 256

struct bpf_subprog_arg_info {
        enum bpf_arg_type arg_type;
        union {
                u32 mem_size;
                u32 btf_id;
        };
};

enum priv_stack_mode {
        PRIV_STACK_UNKNOWN,
        NO_PRIV_STACK,
        PRIV_STACK_ADAPTIVE,
};

struct bpf_subprog_info {
        const char *name; /* name extracted from BTF */
        u32 start; /* insn idx of function entry point */
        u32 linfo_idx; /* The idx to the main_prog->aux->linfo */
        u32 postorder_start; /* The idx to the env->cfg.insn_postorder */
        u32 exit_idx; /* Index of one of the BPF_EXIT instructions in this subprogram */
        u16 stack_depth; /* max. stack depth used by this function */
        u16 stack_extra;
        u32 insn_processed;
        /* offsets in range [stack_depth .. fastcall_stack_off)
         * are used for bpf_fastcall spills and fills.
         */
        s16 fastcall_stack_off;
        bool has_tail_call: 1;
        bool might_throw: 1;
        bool tail_call_reachable: 1;
        bool has_ld_abs: 1;
        bool is_cb: 1;
        bool is_async_cb: 1;
        bool is_exception_cb: 1;
        bool args_cached: 1;
        /* true if bpf_fastcall stack region is used by functions that can't be inlined */
        bool keep_fastcall_stack: 1;
        bool changes_pkt_data: 1;
        bool might_sleep: 1;
        u8 arg_cnt:4;

        enum priv_stack_mode priv_stack_mode;
        struct bpf_subprog_arg_info args[MAX_BPF_FUNC_ARGS];
        u16 stack_arg_cnt; /* incoming + max outgoing */
        u16 max_out_stack_arg_cnt;
};

static inline u16 bpf_in_stack_arg_cnt(const struct bpf_subprog_info *sub)
{
        if (sub->arg_cnt > MAX_BPF_FUNC_REG_ARGS)
                return sub->arg_cnt - MAX_BPF_FUNC_REG_ARGS;
        return 0;
}

struct bpf_verifier_env;

struct backtrack_state {
        struct bpf_verifier_env *env;
        u32 frame;
        u32 reg_masks[MAX_CALL_FRAMES];
        u64 stack_masks[MAX_CALL_FRAMES];
        u8 stack_arg_masks[MAX_CALL_FRAMES];
};

struct bpf_id_pair {
        u32 old;
        u32 cur;
};

struct bpf_idmap {
        u32 tmp_id_gen;
        u32 cnt;
        struct bpf_id_pair map[BPF_ID_MAP_SIZE];
};

struct bpf_idset {
        u32 num_ids;
        struct {
                u32 id;
                u32 cnt;
        } entries[BPF_ID_MAP_SIZE];
};

/* see verifier.c:compute_scc_callchain() */
struct bpf_scc_callchain {
        /* call sites from bpf_verifier_state->frame[*]->callsite leading to this SCC */
        u32 callsites[MAX_CALL_FRAMES - 1];
        /* last frame in a chain is identified by SCC id */
        u32 scc;
};

/* verifier state waiting for propagate_backedges() */
struct bpf_scc_backedge {
        struct bpf_scc_backedge *next;
        struct bpf_verifier_state state;
};

struct bpf_scc_visit {
        struct bpf_scc_callchain callchain;
        /* first state in current verification path that entered SCC
         * identified by the callchain
         */
        struct bpf_verifier_state *entry_state;
        struct bpf_scc_backedge *backedges; /* list of backedges */
        u32 num_backedges;
};

/* An array of bpf_scc_visit structs sharing tht same bpf_scc_callchain->scc
 * but having different bpf_scc_callchain->callsites.
 */
struct bpf_scc_info {
        u32 num_visits;
        struct bpf_scc_visit visits[];
};

struct bpf_liveness;

/* single container for all structs
 * one verifier_env per bpf_check() call
 */
struct bpf_verifier_env {
        u32 insn_idx;
        u32 prev_insn_idx;
        struct bpf_prog *prog;          /* eBPF program being verified */
        const struct bpf_verifier_ops *ops;
        struct module *attach_btf_mod;  /* The owner module of prog->aux->attach_btf */
        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 */
        bool test_state_freq;           /* test verifier with different pruning frequency */
        bool test_reg_invariants;       /* fail verification on register invariants violations */
        struct bpf_verifier_state *cur_state; /* current verifier state */
        /* Search pruning optimization, array of list_heads for
         * lists of struct bpf_verifier_state_list.
         */
        struct list_head *explored_states;
        struct list_head free_list;     /* list of struct bpf_verifier_state_list */
        struct bpf_map *used_maps[MAX_USED_MAPS]; /* array of map's used by eBPF program */
        struct btf_mod_pair used_btfs[MAX_USED_BTFS]; /* array of BTF's used by BPF program */
        struct bpf_map *insn_array_maps[MAX_USED_MAPS]; /* array of INSN_ARRAY map's to be relocated */
        u32 used_map_cnt;               /* number of used maps */
        u32 used_btf_cnt;               /* number of used BTF objects */
        u32 insn_array_map_cnt;         /* number of used maps of type BPF_MAP_TYPE_INSN_ARRAY */
        u32 id_gen;                     /* used to generate unique reg IDs */
        u32 hidden_subprog_cnt;         /* number of hidden subprogs */
        int exception_callback_subprog;
        bool explore_alu_limits;
        bool allow_ptr_leaks;
        /* Allow access to uninitialized stack memory. Writes with fixed offset are
         * always allowed, so this refers to reads (with fixed or variable offset),
         * to writes with variable offset and to indirect (helper) accesses.
         */
        bool allow_uninit_stack;
        bool bpf_capable;
        bool bypass_spec_v1;
        bool bypass_spec_v4;
        bool seen_direct_write;
        bool seen_exception;
        struct bpf_insn_aux_data *insn_aux_data; /* array of per-insn state */
        const struct bpf_line_info *prev_linfo;
        struct bpf_verifier_log log;
        struct bpf_subprog_info subprog_info[BPF_MAX_SUBPROGS + 2]; /* max + 2 for the fake and exception subprogs */
        /* subprog indices sorted in topological order: leaves first, callers last */
        int subprog_topo_order[BPF_MAX_SUBPROGS + 2];
        union {
                struct bpf_idmap idmap_scratch;
                struct bpf_idset idset_scratch;
        };
        struct {
                int *insn_state;
                int *insn_stack;
                /*
                 * vector of instruction indexes sorted in post-order, grouped by subprogram,
                 * see bpf_subprog_info->postorder_start.
                 */
                int *insn_postorder;
                int cur_stack;
                /* current position in the insn_postorder vector */
                int cur_postorder;
        } cfg;
        struct backtrack_state bt;
        struct bpf_jmp_history_entry *cur_hist_ent;
        /* Per-callsite copy of parent's converged at_stack_in for cross-frame fills. */
        struct arg_track **callsite_at_stack;
        u32 pass_cnt; /* number of times do_check() was called */
        u32 subprog_cnt;
        /* number of instructions analyzed by the verifier */
        u32 prev_insn_processed, insn_processed;
        /* number of jmps, calls, exits analyzed so far */
        u32 prev_jmps_processed, jmps_processed;
        /* maximum combined stack depth */
        u32 max_stack_depth;
        /* total verification time */
        u64 verification_time;
        /* maximum number of verifier states kept in 'branching' instructions */
        u32 max_states_per_insn;
        /* total number of allocated verifier states */
        u32 total_states;
        /* some states are freed during program analysis.
         * this is peak number of states. this number dominates kernel
         * memory consumption during verification
         */
        u32 peak_states;
        /* longest register parentage chain walked for liveness marking */
        u32 longest_mark_read_walk;
        u32 free_list_size;
        u32 explored_states_size;
        u32 num_backedges;
        bpfptr_t fd_array;

        /* bit mask to keep track of whether a register has been accessed
         * since the last time the function state was printed
         */
        u32 scratched_regs;
        /* Same as scratched_regs but for stack slots */
        u64 scratched_stack_slots;
        u64 prev_log_pos, prev_insn_print_pos;
        /* buffer used to temporary hold constants as scalar registers */
        struct bpf_reg_state fake_reg[1];
        /* buffers used to save updated reg states while simulating branches */
        struct bpf_reg_state true_reg1, true_reg2, false_reg1, false_reg2;
        /* buffer used to generate temporary string representations,
         * e.g., in reg_type_str() to generate reg_type string
         */
        char tmp_str_buf[TMP_STR_BUF_LEN];
        char tmp_arg_name[32];
        struct bpf_insn insn_buf[INSN_BUF_SIZE];
        struct bpf_insn epilogue_buf[INSN_BUF_SIZE];
        struct bpf_scc_callchain callchain_buf;
        struct bpf_liveness *liveness;
        /* array of pointers to bpf_scc_info indexed by SCC id */
        struct bpf_scc_info **scc_info;
        u32 scc_cnt;
        struct bpf_iarray *succ;
        struct bpf_iarray *gotox_tmp_buf;
};

static inline struct bpf_func_info_aux *subprog_aux(struct bpf_verifier_env *env, int subprog)
{
        return &env->prog->aux->func_info_aux[subprog];
}

static inline struct bpf_subprog_info *subprog_info(struct bpf_verifier_env *env, int subprog)
{
        return &env->subprog_info[subprog];
}

struct bpf_call_summary {
        u8 num_params;
        bool is_void;
        bool fastcall;
};

static inline bool bpf_helper_call(const struct bpf_insn *insn)
{
        return insn->code == (BPF_JMP | BPF_CALL) &&
               insn->src_reg == 0;
}

static inline bool bpf_pseudo_call(const struct bpf_insn *insn)
{
        return insn->code == (BPF_JMP | BPF_CALL) &&
               insn->src_reg == BPF_PSEUDO_CALL;
}

static inline bool bpf_pseudo_kfunc_call(const struct bpf_insn *insn)
{
        return insn->code == (BPF_JMP | BPF_CALL) &&
               insn->src_reg == BPF_PSEUDO_KFUNC_CALL;
}

__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, ...);
__printf(2, 3) void bpf_log(struct bpf_verifier_log *log,
                            const char *fmt, ...);
int bpf_vlog_init(struct bpf_verifier_log *log, u32 log_level,
                  char __user *log_buf, u32 log_size);
void bpf_vlog_reset(struct bpf_verifier_log *log, u64 new_pos);
int bpf_vlog_finalize(struct bpf_verifier_log *log, u32 *log_size_actual);

__printf(3, 4) void verbose_linfo(struct bpf_verifier_env *env,
                                  u32 insn_off,
                                  const char *prefix_fmt, ...);

#define verifier_bug_if(cond, env, fmt, args...)                                                \
        ({                                                                                      \
                bool __cond = (cond);                                                           \
                if (unlikely(__cond))                                                           \
                        verifier_bug(env, fmt " (" #cond ")", ##args);                          \
                (__cond);                                                                       \
        })
#define verifier_bug(env, fmt, args...)                                                         \
        ({                                                                                      \
                BPF_WARN_ONCE(1, "verifier bug: " fmt "\n", ##args);                            \
                bpf_log(&env->log, "verifier bug: " fmt "\n", ##args);                          \
        })

static inline void mark_prune_point(struct bpf_verifier_env *env, int idx)
{
        env->insn_aux_data[idx].prune_point = true;
}

static inline bool bpf_is_prune_point(struct bpf_verifier_env *env, int insn_idx)
{
        return env->insn_aux_data[insn_idx].prune_point;
}

static inline void mark_force_checkpoint(struct bpf_verifier_env *env, int idx)
{
        env->insn_aux_data[idx].force_checkpoint = true;
}

static inline bool bpf_is_force_checkpoint(struct bpf_verifier_env *env, int insn_idx)
{
        return env->insn_aux_data[insn_idx].force_checkpoint;
}

static inline void mark_calls_callback(struct bpf_verifier_env *env, int idx)
{
        env->insn_aux_data[idx].calls_callback = true;
}

static inline bool bpf_calls_callback(struct bpf_verifier_env *env, int insn_idx)
{
        return env->insn_aux_data[insn_idx].calls_callback;
}

static inline void mark_jmp_point(struct bpf_verifier_env *env, int idx)
{
        env->insn_aux_data[idx].jmp_point = true;
}

static inline struct bpf_func_state *cur_func(struct bpf_verifier_env *env)
{
        struct bpf_verifier_state *cur = env->cur_state;

        return cur->frame[cur->curframe];
}

static inline struct bpf_reg_state *cur_regs(struct bpf_verifier_env *env)
{
        return cur_func(env)->regs;
}

int bpf_prog_offload_verifier_prep(struct bpf_prog *prog);
int bpf_prog_offload_verify_insn(struct bpf_verifier_env *env,
                                 int insn_idx, int prev_insn_idx);
int bpf_prog_offload_finalize(struct bpf_verifier_env *env);
void
bpf_prog_offload_replace_insn(struct bpf_verifier_env *env, u32 off,
                              struct bpf_insn *insn);
void
bpf_prog_offload_remove_insns(struct bpf_verifier_env *env, u32 off, u32 cnt);

/* this lives here instead of in bpf.h because it needs to dereference tgt_prog */
static inline u64 bpf_trampoline_compute_key(const struct bpf_prog *tgt_prog,
                                             struct btf *btf, u32 btf_id)
{
        if (tgt_prog)
                return ((u64)tgt_prog->aux->id << 32) | btf_id;
        else
                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_btf_info_early(struct bpf_verifier_env *env,
                             const union bpf_attr *attr, bpfptr_t uattr);
int bpf_check_btf_info(struct bpf_verifier_env *env,
                       const union bpf_attr *attr, bpfptr_t uattr);

int bpf_check_attach_target(struct bpf_verifier_log *log,
                            const struct bpf_prog *prog,
                            const struct bpf_prog *tgt_prog,
                            u32 btf_id,
                            struct bpf_attach_target_info *tgt_info);
void bpf_free_kfunc_btf_tab(struct bpf_kfunc_btf_tab *tab);

int mark_chain_precision(struct bpf_verifier_env *env, int regno);

int bpf_is_state_visited(struct bpf_verifier_env *env, int insn_idx);
int bpf_update_branch_counts(struct bpf_verifier_env *env, struct bpf_verifier_state *st);

void bpf_clear_jmp_history(struct bpf_verifier_state *state);
int bpf_copy_verifier_state(struct bpf_verifier_state *dst_state,
                            const struct bpf_verifier_state *src);
struct list_head *bpf_explored_state(struct bpf_verifier_env *env, int idx);
void bpf_free_verifier_state(struct bpf_verifier_state *state, bool free_self);
void bpf_free_backedges(struct bpf_scc_visit *visit);
int bpf_push_jmp_history(struct bpf_verifier_env *env, struct bpf_verifier_state *cur,
                         int insn_flags, int spi, int frame, u64 linked_regs);
void bpf_bt_sync_linked_regs(struct backtrack_state *bt, struct bpf_jmp_history_entry *hist);
void bpf_mark_reg_not_init(const struct bpf_verifier_env *env,
                           struct bpf_reg_state *reg);
void bpf_mark_reg_unknown_imprecise(struct bpf_reg_state *reg);
void bpf_mark_all_scalars_precise(struct bpf_verifier_env *env,
                                  struct bpf_verifier_state *st);
void bpf_clear_singular_ids(struct bpf_verifier_env *env, struct bpf_verifier_state *st);
int bpf_mark_chain_precision(struct bpf_verifier_env *env,
                             struct bpf_verifier_state *starting_state,
                             int regno, bool *changed);

static inline int bpf_get_spi(s32 off)
{
        return (-off - 1) / BPF_REG_SIZE;
}

static inline struct bpf_func_state *bpf_func(struct bpf_verifier_env *env,
                                              const struct bpf_reg_state *reg)
{
        struct bpf_verifier_state *cur = env->cur_state;

        return cur->frame[reg->frameno];
}

/* Return IP for a given frame in a call stack */
static inline u32 bpf_frame_insn_idx(struct bpf_verifier_state *st, u32 frame)
{
        return frame == st->curframe
               ? st->insn_idx
               : st->frame[frame + 1]->callsite;
}

static inline bool bpf_is_jmp_point(struct bpf_verifier_env *env, int insn_idx)
{
        return env->insn_aux_data[insn_idx].jmp_point;
}

static inline bool bpf_is_spilled_reg(const struct bpf_stack_state *stack)
{
        return stack->slot_type[BPF_REG_SIZE - 1] == STACK_SPILL;
}

static inline bool bpf_is_spilled_scalar_reg(const struct bpf_stack_state *stack)
{
        return bpf_is_spilled_reg(stack) && stack->spilled_ptr.type == SCALAR_VALUE;
}

static inline bool bpf_register_is_null(struct bpf_reg_state *reg)
{
        return reg->type == SCALAR_VALUE && tnum_equals_const(reg->var_off, 0);
}

static inline void bpf_bt_set_frame_reg(struct backtrack_state *bt, u32 frame, u32 reg)
{
        bt->reg_masks[frame] |= 1 << reg;
}

static inline void bpf_bt_set_frame_slot(struct backtrack_state *bt, u32 frame, u32 slot)
{
        bt->stack_masks[frame] |= 1ull << slot;
}

static inline void bt_set_frame_stack_arg_slot(struct backtrack_state *bt, u32 frame, u32 slot)
{
        bt->stack_arg_masks[frame] |= 1 << slot;
}

static inline bool bt_is_frame_reg_set(struct backtrack_state *bt, u32 frame, u32 reg)
{
        return bt->reg_masks[frame] & (1 << reg);
}

static inline bool bt_is_frame_slot_set(struct backtrack_state *bt, u32 frame, u32 slot)
{
        return bt->stack_masks[frame] & (1ull << slot);
}

bool bpf_map_is_rdonly(const struct bpf_map *map);
int bpf_map_direct_read(struct bpf_map *map, int off, int size, u64 *val,
                        bool is_ldsx);

#define BPF_BASE_TYPE_MASK      GENMASK(BPF_BASE_TYPE_BITS - 1, 0)

/* extract base type from bpf_{arg, return, reg}_type. */
static inline u32 base_type(u32 type)
{
        return type & BPF_BASE_TYPE_MASK;
}

/* extract flags from an extended type. See bpf_type_flag in bpf.h. */
static inline u32 type_flag(u32 type)
{
        return type & ~BPF_BASE_TYPE_MASK;
}

/* only use after check_attach_btf_id() */
static inline enum bpf_prog_type resolve_prog_type(const struct bpf_prog *prog)
{
        return (prog->type == BPF_PROG_TYPE_EXT && prog->aux->saved_dst_prog_type) ?
                prog->aux->saved_dst_prog_type : prog->type;
}

static inline bool bpf_prog_check_recur(const struct bpf_prog *prog)
{
        switch (resolve_prog_type(prog)) {
        case BPF_PROG_TYPE_TRACING:
                return prog->expected_attach_type != BPF_TRACE_ITER;
        case BPF_PROG_TYPE_STRUCT_OPS:
                return prog->aux->jits_use_priv_stack;
        case BPF_PROG_TYPE_LSM:
        case BPF_PROG_TYPE_SYSCALL:
                return false;
        default:
                return true;
        }
}

#define BPF_REG_TRUSTED_MODIFIERS (MEM_ALLOC | PTR_TRUSTED | NON_OWN_REF)

static inline bool bpf_type_has_unsafe_modifiers(u32 type)
{
        return type_flag(type) & ~BPF_REG_TRUSTED_MODIFIERS;
}

static inline bool type_is_ptr_alloc_obj(u32 type)
{
        return base_type(type) == PTR_TO_BTF_ID && type_flag(type) & MEM_ALLOC;
}

static inline bool type_is_non_owning_ref(u32 type)
{
        return type_is_ptr_alloc_obj(type) && type_flag(type) & NON_OWN_REF;
}

static inline bool type_is_pkt_pointer(enum bpf_reg_type type)
{
        type = base_type(type);
        return type == PTR_TO_PACKET ||
               type == PTR_TO_PACKET_META;
}

static inline bool type_is_sk_pointer(enum bpf_reg_type type)
{
        return type == PTR_TO_SOCKET ||
                type == PTR_TO_SOCK_COMMON ||
                type == PTR_TO_TCP_SOCK ||
                type == PTR_TO_XDP_SOCK;
}

static inline bool type_may_be_null(u32 type)
{
        return type & PTR_MAYBE_NULL;
}

static inline void mark_reg_scratched(struct bpf_verifier_env *env, u32 regno)
{
        env->scratched_regs |= 1U << regno;
}

static inline void mark_stack_slot_scratched(struct bpf_verifier_env *env, u32 spi)
{
        env->scratched_stack_slots |= 1ULL << spi;
}

static inline bool reg_scratched(const struct bpf_verifier_env *env, u32 regno)
{
        return (env->scratched_regs >> regno) & 1;
}

static inline bool stack_slot_scratched(const struct bpf_verifier_env *env, u64 regno)
{
        return (env->scratched_stack_slots >> regno) & 1;
}

static inline bool verifier_state_scratched(const struct bpf_verifier_env *env)
{
        return env->scratched_regs || env->scratched_stack_slots;
}

static inline void mark_verifier_state_clean(struct bpf_verifier_env *env)
{
        env->scratched_regs = 0U;
        env->scratched_stack_slots = 0ULL;
}

/* Used for printing the entire verifier state. */
static inline void mark_verifier_state_scratched(struct bpf_verifier_env *env)
{
        env->scratched_regs = ~0U;
        env->scratched_stack_slots = ~0ULL;
}

static inline bool bpf_stack_narrow_access_ok(int off, int fill_size, int spill_size)
{
#ifdef __BIG_ENDIAN
        off -= spill_size - fill_size;
#endif

        return !(off % BPF_REG_SIZE);
}

static inline bool insn_is_gotox(struct bpf_insn *insn)
{
        return BPF_CLASS(insn->code) == BPF_JMP &&
               BPF_OP(insn->code) == BPF_JA &&
               BPF_SRC(insn->code) == BPF_X;
}

const char *reg_type_str(struct bpf_verifier_env *env, enum bpf_reg_type type);
const char *dynptr_type_str(enum bpf_dynptr_type type);
const char *iter_type_str(const struct btf *btf, u32 btf_id);
const char *iter_state_str(enum bpf_iter_state state);

void print_verifier_state(struct bpf_verifier_env *env, const struct bpf_verifier_state *vstate,
                          u32 frameno, bool print_all);
void print_insn_state(struct bpf_verifier_env *env, const struct bpf_verifier_state *vstate,
                      u32 frameno);
u32 bpf_vlog_alignment(u32 pos);

struct bpf_subprog_info *bpf_find_containing_subprog(struct bpf_verifier_env *env, int off);
int bpf_jmp_offset(struct bpf_insn *insn);
struct bpf_iarray *bpf_insn_successors(struct bpf_verifier_env *env, u32 idx);
void bpf_fmt_stack_mask(char *buf, ssize_t buf_sz, u64 stack_mask);
bool bpf_subprog_is_global(const struct bpf_verifier_env *env, int subprog);

int bpf_find_subprog(struct bpf_verifier_env *env, int off);
bool bpf_is_throw_kfunc(struct bpf_insn *insn);
int bpf_compute_const_regs(struct bpf_verifier_env *env);
int bpf_prune_dead_branches(struct bpf_verifier_env *env);
int bpf_check_cfg(struct bpf_verifier_env *env);
int bpf_compute_postorder(struct bpf_verifier_env *env);
int bpf_compute_scc(struct bpf_verifier_env *env);

struct bpf_map_desc {
        struct bpf_map *ptr;
        int uid;
};

/* The last initialized dynptr; Populated by process_dynptr_func() */
struct bpf_dynptr_desc {
        enum bpf_dynptr_type type;
        u32 id;
        u32 parent_id;
};

/*
 * The last seen rereferenced object; Updated by update_ref_obj() when a register refers to a
 * referenced object. Used when the helper or kfunc is casting a referenced object, returning
 * allocated memory derived from referenced object or creating a dynptr with a referenced
 * object as parent.
 */
struct ref_obj_desc {
        u32 id;
        u32 parent_id;
        u8 cnt;
};

struct bpf_kfunc_call_arg_meta {
        /* In parameters */
        struct btf *btf;
        u32 func_id;
        u32 kfunc_flags;
        const struct btf_type *func_proto;
        const char *func_name;
        /* Out parameters */
        u8 release_regno;
        bool r0_rdonly;
        u32 ret_btf_id;
        u64 r0_size;
        u32 subprogno;
        struct {
                u64 value;
                bool found;
        } arg_constant;

        /* arg_{btf,btf_id,owning_ref} are used by kfunc-specific handling,
         * generally to pass info about user-defined local kptr types to later
         * verification logic
         *   bpf_obj_drop/bpf_percpu_obj_drop
         *     Record the local kptr type to be drop'd
         *   bpf_refcount_acquire (via KF_ARG_PTR_TO_REFCOUNTED_KPTR arg type)
         *     Record the local kptr type to be refcount_incr'd and use
         *     arg_owning_ref to determine whether refcount_acquire should be
         *     fallible
         */
        struct btf *arg_btf;
        u32 arg_btf_id;
        bool arg_owning_ref;
        bool arg_prog;

        struct {
                struct btf_field *field;
        } arg_list_head;
        struct {
                struct btf_field *field;
        } arg_rbtree_root;
        struct {
                u8 spi;
                u8 frameno;
        } iter;
        struct bpf_map_desc map;
        struct bpf_dynptr_desc dynptr;
        struct ref_obj_desc ref_obj;
        u64 mem_size;
};

int bpf_get_helper_proto(struct bpf_verifier_env *env, int func_id,
                         const struct bpf_func_proto **ptr);
int bpf_fetch_kfunc_arg_meta(struct bpf_verifier_env *env, s32 func_id,
                             s16 offset, struct bpf_kfunc_call_arg_meta *meta);
bool bpf_is_async_callback_calling_insn(struct bpf_insn *insn);
bool bpf_is_sync_callback_calling_insn(struct bpf_insn *insn);
static inline bool bpf_is_iter_next_kfunc(struct bpf_kfunc_call_arg_meta *meta)
{
        return meta->kfunc_flags & KF_ITER_NEXT;
}

static inline bool bpf_is_kfunc_sleepable(struct bpf_kfunc_call_arg_meta *meta)
{
        return meta->kfunc_flags & KF_SLEEPABLE;
}
bool bpf_is_kfunc_pkt_changing(struct bpf_kfunc_call_arg_meta *meta);
struct bpf_iarray *bpf_iarray_realloc(struct bpf_iarray *old, size_t n_elem);
int bpf_copy_insn_array_uniq(struct bpf_map *map, u32 start, u32 end, u32 *off);
bool bpf_insn_is_cond_jump(u8 code);
bool bpf_is_may_goto_insn(struct bpf_insn *insn);

void bpf_verbose_insn(struct bpf_verifier_env *env, struct bpf_insn *insn);
bool bpf_get_call_summary(struct bpf_verifier_env *env, struct bpf_insn *call,
                          struct bpf_call_summary *cs);
s64 bpf_helper_stack_access_bytes(struct bpf_verifier_env *env,
                                  struct bpf_insn *insn, int arg,
                                  int insn_idx);
s64 bpf_kfunc_stack_access_bytes(struct bpf_verifier_env *env,
                                 struct bpf_insn *insn, int arg,
                                 int insn_idx);
int bpf_compute_subprog_arg_access(struct bpf_verifier_env *env);

int bpf_stack_liveness_init(struct bpf_verifier_env *env);
void bpf_stack_liveness_free(struct bpf_verifier_env *env);
int bpf_live_stack_query_init(struct bpf_verifier_env *env, struct bpf_verifier_state *st);
bool bpf_stack_slot_alive(struct bpf_verifier_env *env, u32 frameno, u32 spi);
int bpf_compute_live_registers(struct bpf_verifier_env *env);

#define BPF_MAP_KEY_POISON      (1ULL << 63)
#define BPF_MAP_KEY_SEEN        (1ULL << 62)

static inline bool bpf_map_ptr_poisoned(const struct bpf_insn_aux_data *aux)
{
        return aux->map_ptr_state.poison;
}

static inline bool bpf_map_ptr_unpriv(const struct bpf_insn_aux_data *aux)
{
        return aux->map_ptr_state.unpriv;
}

static inline bool bpf_map_key_poisoned(const struct bpf_insn_aux_data *aux)
{
        return aux->map_key_state & BPF_MAP_KEY_POISON;
}

static inline bool bpf_map_key_unseen(const struct bpf_insn_aux_data *aux)
{
        return !(aux->map_key_state & BPF_MAP_KEY_SEEN);
}

static inline u64 bpf_map_key_immediate(const struct bpf_insn_aux_data *aux)
{
        return aux->map_key_state & ~(BPF_MAP_KEY_SEEN | BPF_MAP_KEY_POISON);
}

#define MAX_PACKET_OFF 0xffff
#define CALLER_SAVED_REGS 6

enum bpf_reg_arg_type {
        SRC_OP,         /* register is used as source operand */
        DST_OP,         /* register is used as destination operand */
        DST_OP_NO_MARK  /* same as above, check only, don't mark */
};

#define MAX_KFUNC_DESCS 256

struct bpf_kfunc_desc {
        struct btf_func_model func_model;
        u32 func_id;
        s32 imm;
        u16 offset;
        unsigned long addr;
};

struct bpf_kfunc_desc_tab {
        /* Sorted by func_id (BTF ID) and offset (fd_array offset) during
         * verification. JITs do lookups by bpf_insn, where func_id may not be
         * available, therefore at the end of verification do_misc_fixups()
         * sorts this by imm and offset.
         */
        struct bpf_kfunc_desc descs[MAX_KFUNC_DESCS];
        u32 nr_descs;
};

/* Functions exported from verifier.c, used by fixups.c */
bool bpf_is_reg64(struct bpf_insn *insn, u32 regno, struct bpf_reg_state *reg, enum bpf_reg_arg_type t);
void bpf_clear_insn_aux_data(struct bpf_verifier_env *env, int start, int len);
void bpf_mark_subprog_exc_cb(struct bpf_verifier_env *env, int subprog);
bool bpf_allow_tail_call_in_subprogs(struct bpf_verifier_env *env);
bool bpf_verifier_inlines_helper_call(struct bpf_verifier_env *env, s32 imm);
int bpf_add_kfunc_call(struct bpf_verifier_env *env, u32 func_id, u16 offset);
int bpf_fixup_kfunc_call(struct bpf_verifier_env *env, struct bpf_insn *insn,
                         struct bpf_insn *insn_buf, int insn_idx, int *cnt);

/* Functions exported from verifier.c, used by trampoline.c */
int bpf_check_attach_btf_id_multi(struct btf *btf, struct bpf_prog *prog, u32 btf_id,
                                  struct bpf_attach_target_info *tgt_info);

/* Functions in fixups.c, called from bpf_check() */
int bpf_remove_fastcall_spills_fills(struct bpf_verifier_env *env);
int bpf_optimize_bpf_loop(struct bpf_verifier_env *env);
void bpf_opt_hard_wire_dead_code_branches(struct bpf_verifier_env *env);
int bpf_opt_remove_dead_code(struct bpf_verifier_env *env);
int bpf_opt_remove_nops(struct bpf_verifier_env *env);
int bpf_opt_subreg_zext_lo32_rnd_hi32(struct bpf_verifier_env *env, const union bpf_attr *attr);
int bpf_convert_ctx_accesses(struct bpf_verifier_env *env);
int bpf_jit_subprogs(struct bpf_verifier_env *env);
int bpf_fixup_call_args(struct bpf_verifier_env *env);
int bpf_do_misc_fixups(struct bpf_verifier_env *env);

#endif /* _LINUX_BPF_VERIFIER_H */