Re: [PATCH 2/2] Fix a stack buffer overflow bug in check_input_term

From: Hui Peng
Date: Sun Sep 01 2019 - 15:47:37 EST

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On 9/1/19 9:00 AM, Salvatore Bonaccorso wrote:
> Hi Hui,
> On Fri, Aug 30, 2019 at 05:47:29PM -0400, Hui Peng wrote:
>> `check_input_term` recursively calls itself with input from
>> device side (e.g., uac_input_terminal_descriptor.bCSourceID)
>> as argument (id). In `check_input_term`, if `check_input_term`
>> is called with the same `id` argument as the caller, it triggers
>> endless recursive call, resulting kernel space stack overflow.
>> This patch fixes the bug by adding a bitmap to `struct mixer_build`
>> to keep track of the checked ids and stop the execution if some id
>> has been checked (similar to how parse_audio_unit handles unitid
>> argument).
>> CVE: CVE-2018-15118
> Similar to the previous one, this should be CVE-2019-15118 as far I
> can tell.

Same here: CVE id updated.

Can you apply it to v4.4.190 and v4.14.141?


> Regards,
> Salvatore