cli: Validate cli_file_index on quit command
VPP crash happens with 'vppctl quit quit' command. The 2nd quit command
tries to access the file index which is already freed by the first quit.
This can be avoided to validate cli_file_index.
@@ -2489,6 +2489,10 @@ unix_cli_kill (unix_cli_main_t * cm, uword cli_file_index)
clib_file_t *uf;
int i;
+ /* Validate cli_file_index */
+ if (pool_is_free_index (cm->cli_file_pool, cli_file_index))
+ return;
+
cf = pool_elt_at_index (cm->cli_file_pool, cli_file_index);
uf = pool_elt_at_index (fm->file_pool, cf->clib_file_index);
