Double free vulnerability in do_rename_gpt_parts

[Simon Goldschmidt]

Am 17.01.2020 um 17:31 schrieb Tom Rini:
> On Fri, Jan 17, 2020 at 04:29:52PM +0100, Simon Goldschmidt wrote:
>> + Some contributors of this file
>>
>> On Fri, Jan 17, 2020 at 1:03 PM Jordy <jordy at simplyhacker.com> wrote:
>>>
>>> Hello U-Boot lists!
>>>
>>> I think I found a double free bug in U-Boot, in /cmp/gpt.c in the function do_rename_gpt_parts().
>>>
>>> On line 702 the partition_list is being free'd if ret is smaller than 0.
>>> If the return value is not -ENOMEM it will go to the out: label and free the partition_list again.
>>
>> Reading the code, I can confirm that. Funny enough, the code in question was
>> introduced by commit 18030d04 ("GPT: fix memory leaks identified by Coverity").
>> Although I think Coverity should have detected the resulting double-free...
>>
>> However, I'm not sure of the fix: the code just continues for -ENOMEM and then
>> goes on using partitions_list at line 757...
> 
> So, Coverity later did complain about that change (but not immediately,
> funny enough).  I posted http://patchwork.ozlabs.org/patch/1192036/ and
> was hoping for a review on it as it's complex enough I'd like to avoid
> adding a 3rd round of issues there.  Thanks!
> 

Ah, yes. I've just responded there.

Regards,
Simon