src/http/ngx_http_upstream.c:2441: error: Integer Overflow L2
  ([0, `r->main->count` + 1] - 1):unsigned32 by call to `ngx_http_upstream_process_upgraded`.

src/http/ngx_http_upstream.c:2379:1: Parameter `r->main->count`
2377. 
2378. 
2379. static void
      ^
2380. ngx_http_upstream_upgrade(ngx_http_request_t *r, ngx_http_upstream_t *u)
2381. {

src/http/ngx_http_upstream.c:2441:9: Call
2439.         || r->header_in->pos != r->header_in->last)
2440.     {
2441.         ngx_http_upstream_process_upgraded(r, 0, 1);
              ^
2442.     }
2443. }

src/http/ngx_http_upstream.c:2476:1: Parameter `r->main->count`
  2474. 
  2475. 
  2476. static void
        ^
  2477. ngx_http_upstream_process_upgraded(ngx_http_request_t *r,
  2478.     ngx_uint_t from_upstream, ngx_uint_t do_write)

src/http/ngx_http_upstream.c:2499:9: Call
  2497.         c->timedout = 1;
  2498.         ngx_connection_error(c, NGX_ETIMEDOUT, "client timed out");
  2499.         ngx_http_upstream_finalize_request(r, u, NGX_HTTP_REQUEST_TIME_OUT);
                ^
  2500.         return;
  2501.     }

src/http/ngx_http_upstream.c:3269:1: Parameter `r->main->count`
    3267. 
    3268. 
    3269. static void
          ^
    3270. ngx_http_upstream_finalize_request(ngx_http_request_t *r,
    3271.     ngx_http_upstream_t *u, ngx_int_t rc)

src/http/ngx_http_upstream.c:3401:5: Call
    3399.     }
    3400. 
    3401.     ngx_http_finalize_request(r, rc);
              ^
    3402. }
    3403. 

src/http/ngx_http_request.c:1946:1: Parameter `r->main->count`
      1944. 
      1945. 
      1946. void
            ^
      1947. ngx_http_finalize_request(ngx_http_request_t *r, ngx_int_t rc)
      1948. {

src/http/ngx_http_request.c:1984:13: Call
      1982.         || c->error)
      1983.     {
      1984.         if (ngx_http_post_action(r) == NGX_OK) {
                        ^
      1985.             return;
      1986.         }

src/http/ngx_http_request.c:2963:1: <LHS trace>
2961. 
2962. 
2963. static ngx_int_t
      ^
2964. ngx_http_post_action(ngx_http_request_t *r)
2965. {

src/http/ngx_http_request.c:2963:1: Parameter `r->main->count`
        2961. 
        2962. 
        2963. static ngx_int_t
              ^
        2964. ngx_http_post_action(ngx_http_request_t *r)
        2965. {

src/http/ngx_http_request.c:2981:5: Binary operation: ([0, r->main->count + 1] - 1):unsigned32 by call to `ngx_http_upstream_process_upgraded` 
        2979.                    "post action: \"%V\"", &clcf->post_action);
        2980. 
        2981.     r->main->count--;
                  ^
        2982. 
        2983.     r->http_version = NGX_HTTP_VERSION_9;

static ngx_int_t
ngx_http_post_action(ngx_http_request_t *r)
{
    ngx_http_core_loc_conf_t  *clcf;
    clcf = ngx_http_get_module_loc_conf(r, ngx_http_core_module);
    if (clcf->post_action.data == NULL) {
        return NGX_DECLINED;
    }
    if (r->post_action && r->uri_changes == 0) {
        return NGX_DECLINED;
    }
    ngx_log_debug1(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
                   "post action: \"%V\"", &clcf->post_action);
    r->main->count--;
    r->http_version = NGX_HTTP_VERSION_9;
    r->header_only = 1;
    r->post_action = 1;
    r->read_event_handler = ngx_http_block_reading;
    if (clcf->post_action.data[0] == '/') {
        ngx_http_internal_redirect(r, &clcf->post_action, NULL);
    } else {
        ngx_http_named_location(r, &clcf->post_action);
    }
    return NGX_OK;
}
['static void\nngx_http_upstream_upgrade(ngx_http_request_t *r, ngx_http_upstream_t *u)\n{\n    int                        tcp_nodelay;\n    ngx_connection_t          *c;\n    ngx_http_core_loc_conf_t  *clcf;\n    c = r->connection;\n    clcf = ngx_http_get_module_loc_conf(r, ngx_http_core_module);\n    r->keepalive = 0;\n    c->log->action = "proxying upgraded connection";\n    u->read_event_handler = ngx_http_upstream_upgraded_read_upstream;\n    u->write_event_handler = ngx_http_upstream_upgraded_write_upstream;\n    r->read_event_handler = ngx_http_upstream_upgraded_read_downstream;\n    r->write_event_handler = ngx_http_upstream_upgraded_write_downstream;\n    if (clcf->tcp_nodelay && c->tcp_nodelay == NGX_TCP_NODELAY_UNSET) {\n        ngx_log_debug0(NGX_LOG_DEBUG_HTTP, c->log, 0, "tcp_nodelay");\n        tcp_nodelay = 1;\n        if (setsockopt(c->fd, IPPROTO_TCP, TCP_NODELAY,\n                       (const void *) &tcp_nodelay, sizeof(int)) == -1)\n        {\n            ngx_connection_error(c, ngx_socket_errno,\n                                 "setsockopt(TCP_NODELAY) failed");\n            ngx_http_upstream_finalize_request(r, u, 0);\n            return;\n        }\n        c->tcp_nodelay = NGX_TCP_NODELAY_SET;\n        if (setsockopt(u->peer.connection->fd, IPPROTO_TCP, TCP_NODELAY,\n                       (const void *) &tcp_nodelay, sizeof(int)) == -1)\n        {\n            ngx_connection_error(u->peer.connection, ngx_socket_errno,\n                                 "setsockopt(TCP_NODELAY) failed");\n            ngx_http_upstream_finalize_request(r, u, 0);\n            return;\n        }\n        u->peer.connection->tcp_nodelay = NGX_TCP_NODELAY_SET;\n    }\n    if (ngx_http_send_special(r, NGX_HTTP_FLUSH) == NGX_ERROR) {\n        ngx_http_upstream_finalize_request(r, u, 0);\n        return;\n    }\n    if (u->peer.connection->read->ready\n        || u->buffer.pos != u->buffer.last)\n    {\n        ngx_http_upstream_process_upgraded(r, 1, 1);\n    }\n    if (c->read->ready\n        || r->header_in->pos != r->header_in->last)\n    {\n        ngx_http_upstream_process_upgraded(r, 0, 1);\n    }\n}', 'static void\nngx_http_upstream_process_upgraded(ngx_http_request_t *r,\n    ngx_uint_t from_upstream, ngx_uint_t do_write)\n{\n    size_t                     size;\n    ssize_t                    n;\n    ngx_buf_t                 *b;\n    ngx_connection_t          *c, *downstream, *upstream, *dst, *src;\n    ngx_http_upstream_t       *u;\n    ngx_http_core_loc_conf_t  *clcf;\n    c = r->connection;\n    u = r->upstream;\n    ngx_log_debug1(NGX_LOG_DEBUG_HTTP, c->log, 0,\n                   "http upstream process upgraded, fu:%ui", from_upstream);\n    downstream = c;\n    upstream = u->peer.connection;\n    if (downstream->write->timedout) {\n        c->timedout = 1;\n        ngx_connection_error(c, NGX_ETIMEDOUT, "client timed out");\n        ngx_http_upstream_finalize_request(r, u, NGX_HTTP_REQUEST_TIME_OUT);\n        return;\n    }\n    if (upstream->read->timedout || upstream->write->timedout) {\n        ngx_connection_error(c, NGX_ETIMEDOUT, "upstream timed out");\n        ngx_http_upstream_finalize_request(r, u, 0);\n        return;\n    }\n    if (from_upstream) {\n        src = upstream;\n        dst = downstream;\n        b = &u->buffer;\n    } else {\n        src = downstream;\n        dst = upstream;\n        b = &u->from_client;\n        if (r->header_in->last > r->header_in->pos) {\n            b = r->header_in;\n            b->end = b->last;\n            do_write = 1;\n        }\n        if (b->start == NULL) {\n            b->start = ngx_palloc(r->pool, u->conf->buffer_size);\n            if (b->start == NULL) {\n                ngx_http_upstream_finalize_request(r, u, 0);\n                return;\n            }\n            b->pos = b->start;\n            b->last = b->start;\n            b->end = b->start + u->conf->buffer_size;\n            b->temporary = 1;\n            b->tag = u->output.tag;\n        }\n    }\n    for ( ;; ) {\n        if (do_write) {\n            size = b->last - b->pos;\n            if (size && dst->write->ready) {\n                n = dst->send(dst, b->pos, size);\n                if (n == NGX_ERROR) {\n                    ngx_http_upstream_finalize_request(r, u, 0);\n                    return;\n                }\n                if (n > 0) {\n                    b->pos += n;\n                    if (b->pos == b->last) {\n                        b->pos = b->start;\n                        b->last = b->start;\n                    }\n                }\n            }\n        }\n        size = b->end - b->last;\n        if (size && src->read->ready) {\n            n = src->recv(src, b->last, size);\n            if (n == NGX_AGAIN || n == 0) {\n                break;\n            }\n            if (n > 0) {\n                do_write = 1;\n                b->last += n;\n                continue;\n            }\n            if (n == NGX_ERROR) {\n                src->read->eof = 1;\n            }\n        }\n        break;\n    }\n    if ((upstream->read->eof && u->buffer.pos == u->buffer.last)\n        || (downstream->read->eof && u->from_client.pos == u->from_client.last)\n        || (downstream->read->eof && upstream->read->eof))\n    {\n        ngx_log_debug0(NGX_LOG_DEBUG_HTTP, c->log, 0,\n                       "http upstream upgraded done");\n        ngx_http_upstream_finalize_request(r, u, 0);\n        return;\n    }\n    clcf = ngx_http_get_module_loc_conf(r, ngx_http_core_module);\n    if (ngx_handle_write_event(upstream->write, u->conf->send_lowat)\n        != NGX_OK)\n    {\n        ngx_http_upstream_finalize_request(r, u, 0);\n        return;\n    }\n    if (upstream->write->active && !upstream->write->ready) {\n        ngx_add_timer(upstream->write, u->conf->send_timeout);\n    } else if (upstream->write->timer_set) {\n        ngx_del_timer(upstream->write);\n    }\n    if (ngx_handle_read_event(upstream->read, 0) != NGX_OK) {\n        ngx_http_upstream_finalize_request(r, u, 0);\n        return;\n    }\n    if (upstream->read->active && !upstream->read->ready) {\n        ngx_add_timer(upstream->read, u->conf->read_timeout);\n    } else if (upstream->read->timer_set) {\n        ngx_del_timer(upstream->read);\n    }\n    if (ngx_handle_write_event(downstream->write, clcf->send_lowat)\n        != NGX_OK)\n    {\n        ngx_http_upstream_finalize_request(r, u, 0);\n        return;\n    }\n    if (ngx_handle_read_event(downstream->read, 0) != NGX_OK) {\n        ngx_http_upstream_finalize_request(r, u, 0);\n        return;\n    }\n    if (downstream->write->active && !downstream->write->ready) {\n        ngx_add_timer(downstream->write, clcf->send_timeout);\n    } else if (downstream->write->timer_set) {\n        ngx_del_timer(downstream->write);\n    }\n}', 'static void\nngx_http_upstream_finalize_request(ngx_http_request_t *r,\n    ngx_http_upstream_t *u, ngx_int_t rc)\n{\n    ngx_time_t  *tp;\n    ngx_log_debug1(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,\n                   "finalize http upstream request: %i", rc);\n    if (u->cleanup) {\n        *u->cleanup = NULL;\n        u->cleanup = NULL;\n    }\n    if (u->resolved && u->resolved->ctx) {\n        ngx_resolve_name_done(u->resolved->ctx);\n        u->resolved->ctx = NULL;\n    }\n    if (u->state && u->state->response_sec) {\n        tp = ngx_timeofday();\n        u->state->response_sec = tp->sec - u->state->response_sec;\n        u->state->response_msec = tp->msec - u->state->response_msec;\n        if (u->pipe) {\n            u->state->response_length = u->pipe->read_length;\n        }\n    }\n    u->finalize_request(r, rc);\n    if (u->peer.free) {\n        u->peer.free(&u->peer, u->peer.data, 0);\n    }\n    if (u->peer.connection) {\n#if (NGX_HTTP_SSL)\n        if (u->peer.connection->ssl) {\n            u->peer.connection->ssl->no_wait_shutdown = 1;\n            (void) ngx_ssl_shutdown(u->peer.connection);\n        }\n#endif\n        ngx_log_debug1(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,\n                       "close http upstream connection: %d",\n                       u->peer.connection->fd);\n        if (u->peer.connection->pool) {\n            ngx_destroy_pool(u->peer.connection->pool);\n        }\n        ngx_close_connection(u->peer.connection);\n    }\n    u->peer.connection = NULL;\n    if (u->pipe && u->pipe->temp_file) {\n        ngx_log_debug1(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,\n                       "http upstream temp fd: %d",\n                       u->pipe->temp_file->file.fd);\n    }\n    if (u->store && u->pipe && u->pipe->temp_file\n        && u->pipe->temp_file->file.fd != NGX_INVALID_FILE)\n    {\n        if (ngx_delete_file(u->pipe->temp_file->file.name.data)\n            == NGX_FILE_ERROR)\n        {\n            ngx_log_error(NGX_LOG_CRIT, r->connection->log, ngx_errno,\n                          ngx_delete_file_n " \\"%s\\" failed",\n                          u->pipe->temp_file->file.name.data);\n        }\n    }\n#if (NGX_HTTP_CACHE)\n    if (r->cache) {\n        if (u->cacheable) {\n            if (rc == NGX_HTTP_BAD_GATEWAY || rc == NGX_HTTP_GATEWAY_TIME_OUT) {\n                time_t  valid;\n                valid = ngx_http_file_cache_valid(u->conf->cache_valid, rc);\n                if (valid) {\n                    r->cache->valid_sec = ngx_time() + valid;\n                    r->cache->error = rc;\n                }\n            }\n        }\n        ngx_http_file_cache_free(r->cache, u->pipe->temp_file);\n    }\n#endif\n    if (u->header_sent\n        && rc != NGX_HTTP_REQUEST_TIME_OUT\n        && (rc == NGX_ERROR || rc >= NGX_HTTP_SPECIAL_RESPONSE))\n    {\n        rc = 0;\n    }\n    if (rc == NGX_DECLINED) {\n        return;\n    }\n    r->connection->log->action = "sending to client";\n    if (rc == 0\n        && !r->header_only\n#if (NGX_HTTP_CACHE)\n        && !r->cached\n#endif\n       )\n    {\n        rc = ngx_http_send_special(r, NGX_HTTP_LAST);\n    }\n    ngx_http_finalize_request(r, rc);\n}', 'void\nngx_http_finalize_request(ngx_http_request_t *r, ngx_int_t rc)\n{\n    ngx_connection_t          *c;\n    ngx_http_request_t        *pr;\n    ngx_http_core_loc_conf_t  *clcf;\n    c = r->connection;\n    ngx_log_debug5(NGX_LOG_DEBUG_HTTP, c->log, 0,\n                   "http finalize request: %d, \\"%V?%V\\" a:%d, c:%d",\n                   rc, &r->uri, &r->args, r == c->data, r->main->count);\n    if (rc == NGX_DONE) {\n        ngx_http_finalize_connection(r);\n        return;\n    }\n    if (rc == NGX_OK && r->filter_finalize) {\n        c->error = 1;\n    }\n    if (rc == NGX_DECLINED) {\n        r->content_handler = NULL;\n        r->write_event_handler = ngx_http_core_run_phases;\n        ngx_http_core_run_phases(r);\n        return;\n    }\n    if (r != r->main && r->post_subrequest) {\n        rc = r->post_subrequest->handler(r, r->post_subrequest->data, rc);\n    }\n    if (rc == NGX_ERROR\n        || rc == NGX_HTTP_REQUEST_TIME_OUT\n        || rc == NGX_HTTP_CLIENT_CLOSED_REQUEST\n        || c->error)\n    {\n        if (ngx_http_post_action(r) == NGX_OK) {\n            return;\n        }\n        if (r->main->blocked) {\n            r->write_event_handler = ngx_http_request_finalizer;\n        }\n        ngx_http_terminate_request(r, rc);\n        return;\n    }\n    if (rc >= NGX_HTTP_SPECIAL_RESPONSE\n        || rc == NGX_HTTP_CREATED\n        || rc == NGX_HTTP_NO_CONTENT)\n    {\n        if (rc == NGX_HTTP_CLOSE) {\n            ngx_http_terminate_request(r, rc);\n            return;\n        }\n        if (r == r->main) {\n            if (c->read->timer_set) {\n                ngx_del_timer(c->read);\n            }\n            if (c->write->timer_set) {\n                ngx_del_timer(c->write);\n            }\n        }\n        c->read->handler = ngx_http_request_handler;\n        c->write->handler = ngx_http_request_handler;\n        ngx_http_finalize_request(r, ngx_http_special_response_handler(r, rc));\n        return;\n    }\n    if (r != r->main) {\n        if (r->buffered || r->postponed) {\n            if (ngx_http_set_write_handler(r) != NGX_OK) {\n                ngx_http_terminate_request(r, 0);\n            }\n            return;\n        }\n        pr = r->parent;\n        if (r == c->data) {\n            r->main->count--;\n            r->main->subrequests++;\n            if (!r->logged) {\n                clcf = ngx_http_get_module_loc_conf(r, ngx_http_core_module);\n                if (clcf->log_subrequest) {\n                    ngx_http_log_request(r);\n                }\n                r->logged = 1;\n            } else {\n                ngx_log_error(NGX_LOG_ALERT, c->log, 0,\n                              "subrequest: \\"%V?%V\\" logged again",\n                              &r->uri, &r->args);\n            }\n            r->done = 1;\n            if (pr->postponed && pr->postponed->request == r) {\n                pr->postponed = pr->postponed->next;\n            }\n            c->data = pr;\n        } else {\n            ngx_log_debug2(NGX_LOG_DEBUG_HTTP, c->log, 0,\n                           "http finalize non-active request: \\"%V?%V\\"",\n                           &r->uri, &r->args);\n            r->write_event_handler = ngx_http_request_finalizer;\n            if (r->waited) {\n                r->done = 1;\n            }\n        }\n        if (ngx_http_post_request(pr, NULL) != NGX_OK) {\n            r->main->count++;\n            ngx_http_terminate_request(r, 0);\n            return;\n        }\n        ngx_log_debug2(NGX_LOG_DEBUG_HTTP, c->log, 0,\n                       "http wake parent request: \\"%V?%V\\"",\n                       &pr->uri, &pr->args);\n        return;\n    }\n    if (r->buffered || c->buffered || r->postponed || r->blocked) {\n        if (ngx_http_set_write_handler(r) != NGX_OK) {\n            ngx_http_terminate_request(r, 0);\n        }\n        return;\n    }\n    if (r != c->data) {\n        ngx_log_error(NGX_LOG_ALERT, c->log, 0,\n                      "http finalize non-active request: \\"%V?%V\\"",\n                      &r->uri, &r->args);\n        return;\n    }\n    r->done = 1;\n    r->write_event_handler = ngx_http_request_empty_handler;\n    if (!r->post_action) {\n        r->request_complete = 1;\n    }\n    if (ngx_http_post_action(r) == NGX_OK) {\n        return;\n    }\n    if (c->read->timer_set) {\n        ngx_del_timer(c->read);\n    }\n    if (c->write->timer_set) {\n        c->write->delayed = 0;\n        ngx_del_timer(c->write);\n    }\n    if (c->read->eof) {\n        ngx_http_close_request(r, 0);\n        return;\n    }\n    ngx_http_finalize_connection(r);\n}', 'static ngx_int_t\nngx_http_post_action(ngx_http_request_t *r)\n{\n    ngx_http_core_loc_conf_t  *clcf;\n    clcf = ngx_http_get_module_loc_conf(r, ngx_http_core_module);\n    if (clcf->post_action.data == NULL) {\n        return NGX_DECLINED;\n    }\n    if (r->post_action && r->uri_changes == 0) {\n        return NGX_DECLINED;\n    }\n    ngx_log_debug1(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,\n                   "post action: \\"%V\\"", &clcf->post_action);\n    r->main->count--;\n    r->http_version = NGX_HTTP_VERSION_9;\n    r->header_only = 1;\n    r->post_action = 1;\n    r->read_event_handler = ngx_http_block_reading;\n    if (clcf->post_action.data[0] == \'/\') {\n        ngx_http_internal_redirect(r, &clcf->post_action, NULL);\n    } else {\n        ngx_http_named_location(r, &clcf->post_action);\n    }\n    return NGX_OK;\n}']