printf: Remove unused 'bprintf'

[drm/drm-misc.git] / kernel / bpf / log.c

// SPDX-License-Identifier: GPL-2.0-only
/* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
 * Copyright (c) 2016 Facebook
 * Copyright (c) 2018 Covalent IO, Inc. http://covalent.io
 */
#include <uapi/linux/btf.h>
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/bpf.h>
#include <linux/bpf_verifier.h>
#include <linux/math64.h>
#include <linux/string.h>

#define verbose(env, fmt, args...) bpf_verifier_log_write(env, fmt, ##args)

static bool bpf_verifier_log_attr_valid(const struct bpf_verifier_log *log)
{
        /* ubuf and len_total should both be specified (or not) together */
        if (!!log->ubuf != !!log->len_total)
                return false;
        /* log buf without log_level is meaningless */
        if (log->ubuf && log->level == 0)
                return false;
        if (log->level & ~BPF_LOG_MASK)
                return false;
        if (log->len_total > UINT_MAX >> 2)
                return false;
        return true;
}

int bpf_vlog_init(struct bpf_verifier_log *log, u32 log_level,
                  char __user *log_buf, u32 log_size)
{
        log->level = log_level;
        log->ubuf = log_buf;
        log->len_total = log_size;

        /* log attributes have to be sane */
        if (!bpf_verifier_log_attr_valid(log))
                return -EINVAL;

        return 0;
}

static void bpf_vlog_update_len_max(struct bpf_verifier_log *log, u32 add_len)
{
        /* add_len includes terminal \0, so no need for +1. */
        u64 len = log->end_pos + add_len;

        /* log->len_max could be larger than our current len due to
         * bpf_vlog_reset() calls, so we maintain the max of any length at any
         * previous point
         */
        if (len > UINT_MAX)
                log->len_max = UINT_MAX;
        else if (len > log->len_max)
                log->len_max = len;
}

void bpf_verifier_vlog(struct bpf_verifier_log *log, const char *fmt,
                       va_list args)
{
        u64 cur_pos;
        u32 new_n, n;

        n = vscnprintf(log->kbuf, BPF_VERIFIER_TMP_LOG_SIZE, fmt, args);

        if (log->level == BPF_LOG_KERNEL) {
                bool newline = n > 0 && log->kbuf[n - 1] == '\n';

                pr_err("BPF: %s%s", log->kbuf, newline ? "" : "\n");
                return;
        }

        n += 1; /* include terminating zero */
        bpf_vlog_update_len_max(log, n);

        if (log->level & BPF_LOG_FIXED) {
                /* check if we have at least something to put into user buf */
                new_n = 0;
                if (log->end_pos < log->len_total) {
                        new_n = min_t(u32, log->len_total - log->end_pos, n);
                        log->kbuf[new_n - 1] = '\0';
                }

                cur_pos = log->end_pos;
                log->end_pos += n - 1; /* don't count terminating '\0' */

                if (log->ubuf && new_n &&
                    copy_to_user(log->ubuf + cur_pos, log->kbuf, new_n))
                        goto fail;
        } else {
                u64 new_end, new_start;
                u32 buf_start, buf_end;

                new_end = log->end_pos + n;
                if (new_end - log->start_pos >= log->len_total)
                        new_start = new_end - log->len_total;
                else
                        new_start = log->start_pos;

                log->start_pos = new_start;
                log->end_pos = new_end - 1; /* don't count terminating '\0' */

                if (!log->ubuf)
                        return;

                new_n = min(n, log->len_total);
                cur_pos = new_end - new_n;
                div_u64_rem(cur_pos, log->len_total, &buf_start);
                div_u64_rem(new_end, log->len_total, &buf_end);
                /* new_end and buf_end are exclusive indices, so if buf_end is
                 * exactly zero, then it actually points right to the end of
                 * ubuf and there is no wrap around
                 */
                if (buf_end == 0)
                        buf_end = log->len_total;

                /* if buf_start > buf_end, we wrapped around;
                 * if buf_start == buf_end, then we fill ubuf completely; we
                 * can't have buf_start == buf_end to mean that there is
                 * nothing to write, because we always write at least
                 * something, even if terminal '\0'
                 */
                if (buf_start < buf_end) {
                        /* message fits within contiguous chunk of ubuf */
                        if (copy_to_user(log->ubuf + buf_start,
                                         log->kbuf + n - new_n,
                                         buf_end - buf_start))
                                goto fail;
                } else {
                        /* message wraps around the end of ubuf, copy in two chunks */
                        if (copy_to_user(log->ubuf + buf_start,
                                         log->kbuf + n - new_n,
                                         log->len_total - buf_start))
                                goto fail;
                        if (copy_to_user(log->ubuf,
                                         log->kbuf + n - buf_end,
                                         buf_end))
                                goto fail;
                }
        }

        return;
fail:
        log->ubuf = NULL;
}

void bpf_vlog_reset(struct bpf_verifier_log *log, u64 new_pos)
{
        char zero = 0;
        u32 pos;

        if (WARN_ON_ONCE(new_pos > log->end_pos))
                return;

        if (!bpf_verifier_log_needed(log) || log->level == BPF_LOG_KERNEL)
                return;

        /* if position to which we reset is beyond current log window,
         * then we didn't preserve any useful content and should adjust
         * start_pos to end up with an empty log (start_pos == end_pos)
         */
        log->end_pos = new_pos;
        if (log->end_pos < log->start_pos)
                log->start_pos = log->end_pos;

        if (!log->ubuf)
                return;

        if (log->level & BPF_LOG_FIXED)
                pos = log->end_pos + 1;
        else
                div_u64_rem(new_pos, log->len_total, &pos);

        if (pos < log->len_total && put_user(zero, log->ubuf + pos))
                log->ubuf = NULL;
}

static void bpf_vlog_reverse_kbuf(char *buf, int len)
{
        int i, j;

        for (i = 0, j = len - 1; i < j; i++, j--)
                swap(buf[i], buf[j]);
}

static int bpf_vlog_reverse_ubuf(struct bpf_verifier_log *log, int start, int end)
{
        /* we split log->kbuf into two equal parts for both ends of array */
        int n = sizeof(log->kbuf) / 2, nn;
        char *lbuf = log->kbuf, *rbuf = log->kbuf + n;

        /* Read ubuf's section [start, end) two chunks at a time, from left
         * and right side; within each chunk, swap all the bytes; after that
         * reverse the order of lbuf and rbuf and write result back to ubuf.
         * This way we'll end up with swapped contents of specified
         * [start, end) ubuf segment.
         */
        while (end - start > 1) {
                nn = min(n, (end - start ) / 2);

                if (copy_from_user(lbuf, log->ubuf + start, nn))
                        return -EFAULT;
                if (copy_from_user(rbuf, log->ubuf + end - nn, nn))
                        return -EFAULT;

                bpf_vlog_reverse_kbuf(lbuf, nn);
                bpf_vlog_reverse_kbuf(rbuf, nn);

                /* we write lbuf to the right end of ubuf, while rbuf to the
                 * left one to end up with properly reversed overall ubuf
                 */
                if (copy_to_user(log->ubuf + start, rbuf, nn))
                        return -EFAULT;
                if (copy_to_user(log->ubuf + end - nn, lbuf, nn))
                        return -EFAULT;

                start += nn;
                end -= nn;
        }

        return 0;
}

int bpf_vlog_finalize(struct bpf_verifier_log *log, u32 *log_size_actual)
{
        u32 sublen;
        int err;

        *log_size_actual = 0;
        if (!log || log->level == 0 || log->level == BPF_LOG_KERNEL)
                return 0;

        if (!log->ubuf)
                goto skip_log_rotate;
        /* If we never truncated log, there is nothing to move around. */
        if (log->start_pos == 0)
                goto skip_log_rotate;

        /* Otherwise we need to rotate log contents to make it start from the
         * buffer beginning and be a continuous zero-terminated string. Note
         * that if log->start_pos != 0 then we definitely filled up entire log
         * buffer with no gaps, and we just need to shift buffer contents to
         * the left by (log->start_pos % log->len_total) bytes.
         *
         * Unfortunately, user buffer could be huge and we don't want to
         * allocate temporary kernel memory of the same size just to shift
         * contents in a straightforward fashion. Instead, we'll be clever and
         * do in-place array rotation. This is a leetcode-style problem, which
         * could be solved by three rotations.
         *
         * Let's say we have log buffer that has to be shifted left by 7 bytes
         * (spaces and vertical bar is just for demonstrative purposes):
         *   E F G H I J K | A B C D
         *
         * First, we reverse entire array:
         *   D C B A | K J I H G F E
         *
         * Then we rotate first 4 bytes (DCBA) and separately last 7 bytes
         * (KJIHGFE), resulting in a properly rotated array:
         *   A B C D | E F G H I J K
         *
         * We'll utilize log->kbuf to read user memory chunk by chunk, swap
         * bytes, and write them back. Doing it byte-by-byte would be
         * unnecessarily inefficient. Altogether we are going to read and
         * write each byte twice, for total 4 memory copies between kernel and
         * user space.
         */

        /* length of the chopped off part that will be the beginning;
         * len(ABCD) in the example above
         */
        div_u64_rem(log->start_pos, log->len_total, &sublen);
        sublen = log->len_total - sublen;

        err = bpf_vlog_reverse_ubuf(log, 0, log->len_total);
        err = err ?: bpf_vlog_reverse_ubuf(log, 0, sublen);
        err = err ?: bpf_vlog_reverse_ubuf(log, sublen, log->len_total);
        if (err)
                log->ubuf = NULL;

skip_log_rotate:
        *log_size_actual = log->len_max;

        /* properly initialized log has either both ubuf!=NULL and len_total>0
         * or ubuf==NULL and len_total==0, so if this condition doesn't hold,
         * we got a fault somewhere along the way, so report it back
         */
        if (!!log->ubuf != !!log->len_total)
                return -EFAULT;

        /* did truncation actually happen? */
        if (log->ubuf && log->len_max > log->len_total)
                return -ENOSPC;

        return 0;
}

/* log_level controls verbosity level of eBPF verifier.
 * bpf_verifier_log_write() is used to dump the verification trace to the log,
 * so the user can figure out what's wrong with the program
 */
__printf(2, 3) void bpf_verifier_log_write(struct bpf_verifier_env *env,
                                           const char *fmt, ...)
{
        va_list args;

        if (!bpf_verifier_log_needed(&env->log))
                return;

        va_start(args, fmt);
        bpf_verifier_vlog(&env->log, fmt, args);
        va_end(args);
}
EXPORT_SYMBOL_GPL(bpf_verifier_log_write);

__printf(2, 3) void bpf_log(struct bpf_verifier_log *log,
                            const char *fmt, ...)
{
        va_list args;

        if (!bpf_verifier_log_needed(log))
                return;

        va_start(args, fmt);
        bpf_verifier_vlog(log, fmt, args);
        va_end(args);
}
EXPORT_SYMBOL_GPL(bpf_log);

static const struct bpf_line_info *
find_linfo(const struct bpf_verifier_env *env, u32 insn_off)
{
        const struct bpf_line_info *linfo;
        const struct bpf_prog *prog;
        u32 nr_linfo;
        int l, r, m;

        prog = env->prog;
        nr_linfo = prog->aux->nr_linfo;

        if (!nr_linfo || insn_off >= prog->len)
                return NULL;

        linfo = prog->aux->linfo;
        /* Loop invariant: linfo[l].insn_off <= insns_off.
         * linfo[0].insn_off == 0 which always satisfies above condition.
         * Binary search is searching for rightmost linfo entry that satisfies
         * the above invariant, giving us the desired record that covers given
         * instruction offset.
         */
        l = 0;
        r = nr_linfo - 1;
        while (l < r) {
                /* (r - l + 1) / 2 means we break a tie to the right, so if:
                 * l=1, r=2, linfo[l].insn_off <= insn_off, linfo[r].insn_off > insn_off,
                 * then m=2, we see that linfo[m].insn_off > insn_off, and so
                 * r becomes 1 and we exit the loop with correct l==1.
                 * If the tie was broken to the left, m=1 would end us up in
                 * an endless loop where l and m stay at 1 and r stays at 2.
                 */
                m = l + (r - l + 1) / 2;
                if (linfo[m].insn_off <= insn_off)
                        l = m;
                else
                        r = m - 1;
        }

        return &linfo[l];
}

static const char *ltrim(const char *s)
{
        while (isspace(*s))
                s++;

        return s;
}

__printf(3, 4) void verbose_linfo(struct bpf_verifier_env *env,
                                  u32 insn_off,
                                  const char *prefix_fmt, ...)
{
        const struct bpf_line_info *linfo, *prev_linfo;
        const struct btf *btf;
        const char *s, *fname;

        if (!bpf_verifier_log_needed(&env->log))
                return;

        prev_linfo = env->prev_linfo;
        linfo = find_linfo(env, insn_off);
        if (!linfo || linfo == prev_linfo)
                return;

        /* It often happens that two separate linfo records point to the same
         * source code line, but have differing column numbers. Given verifier
         * log doesn't emit column information, from user perspective we just
         * end up emitting the same source code line twice unnecessarily.
         * So instead check that previous and current linfo record point to
         * the same file (file_name_offs match) and the same line number, and
         * avoid emitting duplicated source code line in such case.
         */
        if (prev_linfo && linfo->file_name_off == prev_linfo->file_name_off &&
            BPF_LINE_INFO_LINE_NUM(linfo->line_col) == BPF_LINE_INFO_LINE_NUM(prev_linfo->line_col))
                return;

        if (prefix_fmt) {
                va_list args;

                va_start(args, prefix_fmt);
                bpf_verifier_vlog(&env->log, prefix_fmt, args);
                va_end(args);
        }

        btf = env->prog->aux->btf;
        s = ltrim(btf_name_by_offset(btf, linfo->line_off));
        verbose(env, "%s", s); /* source code line */

        s = btf_name_by_offset(btf, linfo->file_name_off);
        /* leave only file name */
        fname = strrchr(s, '/');
        fname = fname ? fname + 1 : s;
        verbose(env, " @ %s:%u\n", fname, BPF_LINE_INFO_LINE_NUM(linfo->line_col));

        env->prev_linfo = linfo;
}

static const char *btf_type_name(const struct btf *btf, u32 id)
{
        return btf_name_by_offset(btf, btf_type_by_id(btf, id)->name_off);
}

/* string representation of 'enum bpf_reg_type'
 *
 * Note that reg_type_str() can not appear more than once in a single verbose()
 * statement.
 */
const char *reg_type_str(struct bpf_verifier_env *env, enum bpf_reg_type type)
{
        char postfix[16] = {0}, prefix[64] = {0};
        static const char * const str[] = {
                [NOT_INIT]              = "?",
                [SCALAR_VALUE]          = "scalar",
                [PTR_TO_CTX]            = "ctx",
                [CONST_PTR_TO_MAP]      = "map_ptr",
                [PTR_TO_MAP_VALUE]      = "map_value",
                [PTR_TO_STACK]          = "fp",
                [PTR_TO_PACKET]         = "pkt",
                [PTR_TO_PACKET_META]    = "pkt_meta",
                [PTR_TO_PACKET_END]     = "pkt_end",
                [PTR_TO_FLOW_KEYS]      = "flow_keys",
                [PTR_TO_SOCKET]         = "sock",
                [PTR_TO_SOCK_COMMON]    = "sock_common",
                [PTR_TO_TCP_SOCK]       = "tcp_sock",
                [PTR_TO_TP_BUFFER]      = "tp_buffer",
                [PTR_TO_XDP_SOCK]       = "xdp_sock",
                [PTR_TO_BTF_ID]         = "ptr_",
                [PTR_TO_MEM]            = "mem",
                [PTR_TO_ARENA]          = "arena",
                [PTR_TO_BUF]            = "buf",
                [PTR_TO_FUNC]           = "func",
                [PTR_TO_MAP_KEY]        = "map_key",
                [CONST_PTR_TO_DYNPTR]   = "dynptr_ptr",
        };

        if (type & PTR_MAYBE_NULL) {
                if (base_type(type) == PTR_TO_BTF_ID)
                        strscpy(postfix, "or_null_");
                else
                        strscpy(postfix, "_or_null");
        }

        snprintf(prefix, sizeof(prefix), "%s%s%s%s%s%s%s",
                 type & MEM_RDONLY ? "rdonly_" : "",
                 type & MEM_RINGBUF ? "ringbuf_" : "",
                 type & MEM_USER ? "user_" : "",
                 type & MEM_PERCPU ? "percpu_" : "",
                 type & MEM_RCU ? "rcu_" : "",
                 type & PTR_UNTRUSTED ? "untrusted_" : "",
                 type & PTR_TRUSTED ? "trusted_" : ""
        );

        snprintf(env->tmp_str_buf, TMP_STR_BUF_LEN, "%s%s%s",
                 prefix, str[base_type(type)], postfix);
        return env->tmp_str_buf;
}

const char *dynptr_type_str(enum bpf_dynptr_type type)
{
        switch (type) {
        case BPF_DYNPTR_TYPE_LOCAL:
                return "local";
        case BPF_DYNPTR_TYPE_RINGBUF:
                return "ringbuf";
        case BPF_DYNPTR_TYPE_SKB:
                return "skb";
        case BPF_DYNPTR_TYPE_XDP:
                return "xdp";
        case BPF_DYNPTR_TYPE_INVALID:
                return "<invalid>";
        default:
                WARN_ONCE(1, "unknown dynptr type %d\n", type);
                return "<unknown>";
        }
}

const char *iter_type_str(const struct btf *btf, u32 btf_id)
{
        if (!btf || btf_id == 0)
                return "<invalid>";

        /* we already validated that type is valid and has conforming name */
        return btf_type_name(btf, btf_id) + sizeof(ITER_PREFIX) - 1;
}

const char *iter_state_str(enum bpf_iter_state state)
{
        switch (state) {
        case BPF_ITER_STATE_ACTIVE:
                return "active";
        case BPF_ITER_STATE_DRAINED:
                return "drained";
        case BPF_ITER_STATE_INVALID:
                return "<invalid>";
        default:
                WARN_ONCE(1, "unknown iter state %d\n", state);
                return "<unknown>";
        }
}

static char slot_type_char[] = {
        [STACK_INVALID] = '?',
        [STACK_SPILL]   = 'r',
        [STACK_MISC]    = 'm',
        [STACK_ZERO]    = '0',
        [STACK_DYNPTR]  = 'd',
        [STACK_ITER]    = 'i',
};

static void print_liveness(struct bpf_verifier_env *env,
                           enum bpf_reg_liveness live)
{
        if (live & (REG_LIVE_READ | REG_LIVE_WRITTEN | REG_LIVE_DONE))
            verbose(env, "_");
        if (live & REG_LIVE_READ)
                verbose(env, "r");
        if (live & REG_LIVE_WRITTEN)
                verbose(env, "w");
        if (live & REG_LIVE_DONE)
                verbose(env, "D");
}

#define UNUM_MAX_DECIMAL U16_MAX
#define SNUM_MAX_DECIMAL S16_MAX
#define SNUM_MIN_DECIMAL S16_MIN

static bool is_unum_decimal(u64 num)
{
        return num <= UNUM_MAX_DECIMAL;
}

static bool is_snum_decimal(s64 num)
{
        return num >= SNUM_MIN_DECIMAL && num <= SNUM_MAX_DECIMAL;
}

static void verbose_unum(struct bpf_verifier_env *env, u64 num)
{
        if (is_unum_decimal(num))
                verbose(env, "%llu", num);
        else
                verbose(env, "%#llx", num);
}

static void verbose_snum(struct bpf_verifier_env *env, s64 num)
{
        if (is_snum_decimal(num))
                verbose(env, "%lld", num);
        else
                verbose(env, "%#llx", num);
}

int tnum_strn(char *str, size_t size, struct tnum a)
{
        /* print as a constant, if tnum is fully known */
        if (a.mask == 0) {
                if (is_unum_decimal(a.value))
                        return snprintf(str, size, "%llu", a.value);
                else
                        return snprintf(str, size, "%#llx", a.value);
        }
        return snprintf(str, size, "(%#llx; %#llx)", a.value, a.mask);
}
EXPORT_SYMBOL_GPL(tnum_strn);

static void print_scalar_ranges(struct bpf_verifier_env *env,
                                const struct bpf_reg_state *reg,
                                const char **sep)
{
        /* For signed ranges, we want to unify 64-bit and 32-bit values in the
         * output as much as possible, but there is a bit of a complication.
         * If we choose to print values as decimals, this is natural to do,
         * because negative 64-bit and 32-bit values >= -S32_MIN have the same
         * representation due to sign extension. But if we choose to print
         * them in hex format (see is_snum_decimal()), then sign extension is
         * misleading.
         * E.g., smin=-2 and smin32=-2 are exactly the same in decimal, but in
         * hex they will be smin=0xfffffffffffffffe and smin32=0xfffffffe, two
         * very different numbers.
         * So we avoid sign extension if we choose to print values in hex.
         */
        struct {
                const char *name;
                u64 val;
                bool omit;
        } minmaxs[] = {
                {"smin",   reg->smin_value,         reg->smin_value == S64_MIN},
                {"smax",   reg->smax_value,         reg->smax_value == S64_MAX},
                {"umin",   reg->umin_value,         reg->umin_value == 0},
                {"umax",   reg->umax_value,         reg->umax_value == U64_MAX},
                {"smin32",
                 is_snum_decimal((s64)reg->s32_min_value)
                         ? (s64)reg->s32_min_value
                         : (u32)reg->s32_min_value, reg->s32_min_value == S32_MIN},
                {"smax32",
                 is_snum_decimal((s64)reg->s32_max_value)
                         ? (s64)reg->s32_max_value
                         : (u32)reg->s32_max_value, reg->s32_max_value == S32_MAX},
                {"umin32", reg->u32_min_value,      reg->u32_min_value == 0},
                {"umax32", reg->u32_max_value,      reg->u32_max_value == U32_MAX},
        }, *m1, *m2, *mend = &minmaxs[ARRAY_SIZE(minmaxs)];
        bool neg1, neg2;

        for (m1 = &minmaxs[0]; m1 < mend; m1++) {
                if (m1->omit)
                        continue;

                neg1 = m1->name[0] == 's' && (s64)m1->val < 0;

                verbose(env, "%s%s=", *sep, m1->name);
                *sep = ",";

                for (m2 = m1 + 2; m2 < mend; m2 += 2) {
                        if (m2->omit || m2->val != m1->val)
                                continue;
                        /* don't mix negatives with positives */
                        neg2 = m2->name[0] == 's' && (s64)m2->val < 0;
                        if (neg2 != neg1)
                                continue;
                        m2->omit = true;
                        verbose(env, "%s=", m2->name);
                }

                if (m1->name[0] == 's')
                        verbose_snum(env, m1->val);
                else
                        verbose_unum(env, m1->val);
        }
}

static bool type_is_map_ptr(enum bpf_reg_type t) {
        switch (base_type(t)) {
        case CONST_PTR_TO_MAP:
        case PTR_TO_MAP_KEY:
        case PTR_TO_MAP_VALUE:
                return true;
        default:
                return false;
        }
}

/*
 * _a stands for append, was shortened to avoid multiline statements below.
 * This macro is used to output a comma separated list of attributes.
 */
#define verbose_a(fmt, ...) ({ verbose(env, "%s" fmt, sep, ##__VA_ARGS__); sep = ","; })

static void print_reg_state(struct bpf_verifier_env *env,
                            const struct bpf_func_state *state,
                            const struct bpf_reg_state *reg)
{
        enum bpf_reg_type t;
        const char *sep = "";

        t = reg->type;
        if (t == SCALAR_VALUE && reg->precise)
                verbose(env, "P");
        if (t == SCALAR_VALUE && tnum_is_const(reg->var_off)) {
                verbose_snum(env, reg->var_off.value);
                return;
        }

        verbose(env, "%s", reg_type_str(env, t));
        if (t == PTR_TO_ARENA)
                return;
        if (t == PTR_TO_STACK) {
                if (state->frameno != reg->frameno)
                        verbose(env, "[%d]", reg->frameno);
                if (tnum_is_const(reg->var_off)) {
                        verbose_snum(env, reg->var_off.value + reg->off);
                        return;
                }
        }
        if (base_type(t) == PTR_TO_BTF_ID)
                verbose(env, "%s", btf_type_name(reg->btf, reg->btf_id));
        verbose(env, "(");
        if (reg->id)
                verbose_a("id=%d", reg->id & ~BPF_ADD_CONST);
        if (reg->id & BPF_ADD_CONST)
                verbose(env, "%+d", reg->off);
        if (reg->ref_obj_id)
                verbose_a("ref_obj_id=%d", reg->ref_obj_id);
        if (type_is_non_owning_ref(reg->type))
                verbose_a("%s", "non_own_ref");
        if (type_is_map_ptr(t)) {
                if (reg->map_ptr->name[0])
                        verbose_a("map=%s", reg->map_ptr->name);
                verbose_a("ks=%d,vs=%d",
                          reg->map_ptr->key_size,
                          reg->map_ptr->value_size);
        }
        if (t != SCALAR_VALUE && reg->off) {
                verbose_a("off=");
                verbose_snum(env, reg->off);
        }
        if (type_is_pkt_pointer(t)) {
                verbose_a("r=");
                verbose_unum(env, reg->range);
        }
        if (base_type(t) == PTR_TO_MEM) {
                verbose_a("sz=");
                verbose_unum(env, reg->mem_size);
        }
        if (t == CONST_PTR_TO_DYNPTR)
                verbose_a("type=%s",  dynptr_type_str(reg->dynptr.type));
        if (tnum_is_const(reg->var_off)) {
                /* a pointer register with fixed offset */
                if (reg->var_off.value) {
                        verbose_a("imm=");
                        verbose_snum(env, reg->var_off.value);
                }
        } else {
                print_scalar_ranges(env, reg, &sep);
                if (!tnum_is_unknown(reg->var_off)) {
                        char tn_buf[48];

                        tnum_strn(tn_buf, sizeof(tn_buf), reg->var_off);
                        verbose_a("var_off=%s", tn_buf);
                }
        }
        verbose(env, ")");
}

void print_verifier_state(struct bpf_verifier_env *env, const struct bpf_func_state *state,
                          bool print_all)
{
        const struct bpf_reg_state *reg;
        int i;

        if (state->frameno)
                verbose(env, " frame%d:", state->frameno);
        for (i = 0; i < MAX_BPF_REG; i++) {
                reg = &state->regs[i];
                if (reg->type == NOT_INIT)
                        continue;
                if (!print_all && !reg_scratched(env, i))
                        continue;
                verbose(env, " R%d", i);
                print_liveness(env, reg->live);
                verbose(env, "=");
                print_reg_state(env, state, reg);
        }
        for (i = 0; i < state->allocated_stack / BPF_REG_SIZE; i++) {
                char types_buf[BPF_REG_SIZE + 1];
                const char *sep = "";
                bool valid = false;
                u8 slot_type;
                int j;

                if (!print_all && !stack_slot_scratched(env, i))
                        continue;

                for (j = 0; j < BPF_REG_SIZE; j++) {
                        slot_type = state->stack[i].slot_type[j];
                        if (slot_type != STACK_INVALID)
                                valid = true;
                        types_buf[j] = slot_type_char[slot_type];
                }
                types_buf[BPF_REG_SIZE] = 0;
                if (!valid)
                        continue;

                reg = &state->stack[i].spilled_ptr;
                switch (state->stack[i].slot_type[BPF_REG_SIZE - 1]) {
                case STACK_SPILL:
                        /* print MISC/ZERO/INVALID slots above subreg spill */
                        for (j = 0; j < BPF_REG_SIZE; j++)
                                if (state->stack[i].slot_type[j] == STACK_SPILL)
                                        break;
                        types_buf[j] = '\0';

                        verbose(env, " fp%d", (-i - 1) * BPF_REG_SIZE);
                        print_liveness(env, reg->live);
                        verbose(env, "=%s", types_buf);
                        print_reg_state(env, state, reg);
                        break;
                case STACK_DYNPTR:
                        /* skip to main dynptr slot */
                        i += BPF_DYNPTR_NR_SLOTS - 1;
                        reg = &state->stack[i].spilled_ptr;

                        verbose(env, " fp%d", (-i - 1) * BPF_REG_SIZE);
                        print_liveness(env, reg->live);
                        verbose(env, "=dynptr_%s(", dynptr_type_str(reg->dynptr.type));
                        if (reg->id)
                                verbose_a("id=%d", reg->id);
                        if (reg->ref_obj_id)
                                verbose_a("ref_id=%d", reg->ref_obj_id);
                        if (reg->dynptr_id)
                                verbose_a("dynptr_id=%d", reg->dynptr_id);
                        verbose(env, ")");
                        break;
                case STACK_ITER:
                        /* only main slot has ref_obj_id set; skip others */
                        if (!reg->ref_obj_id)
                                continue;

                        verbose(env, " fp%d", (-i - 1) * BPF_REG_SIZE);
                        print_liveness(env, reg->live);
                        verbose(env, "=iter_%s(ref_id=%d,state=%s,depth=%u)",
                                iter_type_str(reg->iter.btf, reg->iter.btf_id),
                                reg->ref_obj_id, iter_state_str(reg->iter.state),
                                reg->iter.depth);
                        break;
                case STACK_MISC:
                case STACK_ZERO:
                default:
                        verbose(env, " fp%d", (-i - 1) * BPF_REG_SIZE);
                        print_liveness(env, reg->live);
                        verbose(env, "=%s", types_buf);
                        break;
                }
        }
        if (state->acquired_refs && state->refs[0].id) {
                verbose(env, " refs=%d", state->refs[0].id);
                for (i = 1; i < state->acquired_refs; i++)
                        if (state->refs[i].id)
                                verbose(env, ",%d", state->refs[i].id);
        }
        if (state->in_callback_fn)
                verbose(env, " cb");
        if (state->in_async_callback_fn)
                verbose(env, " async_cb");
        verbose(env, "\n");
        if (!print_all)
                mark_verifier_state_clean(env);
}

static inline u32 vlog_alignment(u32 pos)
{
        return round_up(max(pos + BPF_LOG_MIN_ALIGNMENT / 2, BPF_LOG_ALIGNMENT),
                        BPF_LOG_MIN_ALIGNMENT) - pos - 1;
}

void print_insn_state(struct bpf_verifier_env *env, const struct bpf_func_state *state)
{
        if (env->prev_log_pos && env->prev_log_pos == env->log.end_pos) {
                /* remove new line character */
                bpf_vlog_reset(&env->log, env->prev_log_pos - 1);
                verbose(env, "%*c;", vlog_alignment(env->prev_insn_print_pos), ' ');
        } else {
                verbose(env, "%d:", env->insn_idx);
        }
        print_verifier_state(env, state, false);
}