src/http/modules/ngx_http_limit_req_module.c:200: error: Integer Overflow L2
  ([0, +oo] - [0, 15]):unsigned64 by call to `ngx_slab_alloc_locked`.

src/http/modules/ngx_http_limit_req_module.c:200:16: Call
198.             + len;
199. 
200.         node = ngx_slab_alloc_locked(ctx->shpool, n);
                    ^
201.         if (node == NULL) {
202. 

src/core/ngx_slab.c:155:1: <LHS trace>
153. 
154. 
155. void *
     ^
156. ngx_slab_alloc_locked(ngx_slab_pool_t *pool, size_t size)
157. {

src/core/ngx_slab.c:155:1: Global `ngx_pagesize_shift`
  153. 
  154. 
  155. void *
       ^
  156. ngx_slab_alloc_locked(ngx_slab_pool_t *pool, size_t size)
  157. {

src/core/ngx_slab.c:288:13: Binary operation: ([0, +oo] - [0, 15]):unsigned64 by call to `ngx_slab_alloc_locked` 
  286.         } else { /* shift > ngx_slab_exact_shift */
  287. 
  288.             n = ngx_pagesize_shift - (page->slab & NGX_SLAB_SHIFT_MASK);
                   ^
  289.             n = 1 << n;
  290.             n = ((uintptr_t) 1 << n) - 1;
