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Subject: Re: [PATCH 2/2] ima: Free IMA measurement buffer after kexec syscall
To:     Thiago Jung Bauermann <bauerman@linux.ibm.com>
Cc:     zohar@linux.ibm.com, dmitry.kasatkin@gmail.com,
        ebiederm@xmission.com, gregkh@linuxfoundation.org,
        sashal@kernel.org, tyhicks@linux.microsoft.com,
        linux-integrity@vger.kernel.org, linux-kernel@vger.kernel.org,
        linuxppc-dev@lists.ozlabs.org
References: <20210121173003.18324-1-nramas@linux.microsoft.com>
 <20210121173003.18324-2-nramas@linux.microsoft.com>
 <87bldg1u3s.fsf@manicouagan.localdomain>
From:   Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Message-ID: <15fb8c53-2aa0-dc5e-123d-87fee78aacb5@linux.microsoft.com>
Date:   Wed, 3 Feb 2021 09:46:40 -0800
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On 1/22/21 2:31 PM, Thiago Jung Bauermann wrote:
> 
> Lakshmi Ramasubramanian <nramas@linux.microsoft.com> writes:
> 
>> IMA allocates kernel virtual memory to carry forward the measurement
>> list, from the current kernel to the next kernel on kexec system call,
>> in ima_add_kexec_buffer() function.  This buffer is not freed before
>> completing the kexec system call resulting in memory leak.
>>
>> Add ima_buffer field in "struct kimage" to store the virtual address
>> of the buffer allocated for the IMA measurement list.
>> Free the memory allocated for the IMA measurement list in
>> kimage_file_post_load_cleanup() function.
>>
>> Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
>> Suggested-by: Tyler Hicks <tyhicks@linux.microsoft.com>
>> Fixes: 7b8589cc29e7 ("ima: on soft reboot, save the measurement list")
> 
> Good catch.
> 
> Reviewed-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
> 

Thanks Thiago.

  -lakshmi