[PATCH] elf: Make string tunables startup-only

[Andreas Schwab]

On Jun 17 2026, Adhemerval Zanella wrote:

> @@ -460,6 +461,12 @@ __tunable_get_val (tunable_id_t id, void *valp, tunable_callback_t callback)
>  	}
>      case TUNABLE_TYPE_STRING:
>  	{
> +	  /* String tunables reference the environment block and are only
> +	     valid during early startup; once sealed they must not be read. */
> +	  if (__glibc_unlikely (cur->sealed))
> +	    _dl_fatal_printf ("Inconsistency detected: trying to read the %s "
> +			      "string tunable after process initialization\n",
> +			      cur->name);

Why do you need the sealed member?  Wouldn't it be enough to check for
NULL in strval?

-- 
Andreas Schwab, SUSE Labs, schwab@suse.de
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