[PATCHv2] malloc: Make sure tcache_key is odd enough

[Andreas Schwab]

On Aug 03 2025, Samuel Thibault wrote:

> @@ -3152,6 +3155,18 @@ tcache_key_initialize (void)
>    if (__getrandom_nocancel_nostatus_direct (&tcache_key, sizeof(tcache_key),
>  					    GRND_NONBLOCK)
>        != sizeof (tcache_key))
> +    tcache_key = 0;
> +
> +  /* We need tcache_key to be non-zero (otherwise tcache_double_free_verify's
> +   * clearing of e->key would go unnoticed and it would loop getting called
> +   * through __libc_free), and we want tcache_key not to be a commonly-occurring
> +   * value in memory, so ensure a minimum amount of one and zero bits.  */

Please use the correct comment style, and fill to less than 80 columns..

-- 
Andreas Schwab, schwab@linux-m68k.org
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