linux-kernel - Re: [ 12/40] hw_random: make buffer usable in scatterlist.

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <87txoetre6.fsf@rustcorp.com.au>
Date:	Thu, 14 Mar 2013 17:11:21 +1030
From:	Rusty Russell <rusty@...tcorp.com.au>
To:	Satoru Takeuchi <satoru.takeuchi@...il.com>,
	Greg Kroah-Hartman <gregkh@...uxfoundation.org>
Cc:	linux-kernel@...r.kernel.org, stable@...r.kernel.org,
	Aurelien Jarno <aurelien@...el32.net>
Subject: Re: [ 12/40] hw_random: make buffer usable in scatterlist.

Satoru Takeuchi <satoru.takeuchi@...il.com> writes:
> Hi Rusty,
>
> At Tue, 12 Mar 2013 15:43:33 -0700,
> Greg Kroah-Hartman wrote:
>> @@ -307,6 +312,14 @@ int hwrng_register(struct hwrng *rng)
>>  
>>  	mutex_lock(&rng_mutex);
>>  
>> +	/* kmalloc makes this safe for virt_to_page() in virtio_rng.c */
>> +	err = -ENOMEM;
>> +	if (!rng_buffer) {
>> +		rng_buffer = kmalloc(rng_buffer_size(), GFP_KERNEL);
>
> rng_buffer is now kmalloc-ed, but not kfree-ed. Shoudn't it be kfree-ed
> at hwrng_unregister()? If my suspect is correct, the same problem is
> in 3.8.3-rc1 and 3.0.69-rc1. I'm OK to make a patch, but it'll be after
> some hours.
>
> Corecct me if I'm wrong.

Yes, it would be nice to free it, but it really makes sense to free it
in module_cleanup() (which would have to be written, as the module
currently doesn't have one).

Cheers,
Rusty.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/