Re: [PATCH 2/2] ima: Free IMA measurement buffer after kexec syscall

From: Lakshmi Ramasubramanian
Date: Wed Feb 03 2021 - 12:47:40 EST


On 1/22/21 2:31 PM, Thiago Jung Bauermann wrote:

Lakshmi Ramasubramanian <nramas@xxxxxxxxxxxxxxxxxxx> 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@xxxxxxxxxxxxxxxxxxx>
Suggested-by: Tyler Hicks <tyhicks@xxxxxxxxxxxxxxxxxxx>
Fixes: 7b8589cc29e7 ("ima: on soft reboot, save the measurement list")

Good catch.

Reviewed-by: Thiago Jung Bauermann <bauerman@xxxxxxxxxxxxx>


Thanks Thiago.

-lakshmi