Hello! FYI, in arch/arm/mach-imx/imx8m/soc.c enable_tzc380() U-Boot configures region0 to allow secure and non-secure world access. This is known to be problematic and allows circumventing the TrustZone due to memory aliasing[0][1].
It causes also recent OP-TEE to panic at startup: E/TC:0 0 Panic 'region0 is not secure configured, non-secure memory alias access possible!' at core/arch/arm/plat-imx/tzc380.c:217 <imx_configure_tzasc> This is not a theoretical issue. On my i.mx8mm evk Board I was able to exploit this and dump all OP-TEE memory from Linux. Thanks, //richard [0] https://github.com/ARM-software/arm-trusted-firmware/commit/9bf148071aad597e7fe7d1080c00aeb35b67a3dd [1] https://github.com/OP-TEE/optee_os/commit/443c5817de47f1bd19091b419806898070382a67 -- sigma star gmbh | Eduard-Bodem-Gasse 6, 6020 Innsbruck, AUT UID/VAT Nr: ATU 66964118 | FN: 374287y
