rpmb: check return value from essiv call
rpmb: check return value from essiv call

An error in the function essiv, as for example memory allocation failure
could result in an uninitialized IV, which means that the IV used for
en/decryption would consist of data previously stored at this memory
location. This could eventually corrupt the filesystem.

Fixes: "Return value of cryptographic function is unchecked" by Riscure.

Signed-off-by: Joakim Bech <741f90e2a7f4d9afbad8bd50be20560f4cf38962@linaro.org>
Tested-by: Joakim Bech <741f90e2a7f4d9afbad8bd50be20560f4cf38962@linaro.org> (QEMU v7, v8)
Reviewed-by: Jens Wiklander <7706914404370d7502c27a0eff493dcf491feb51@linaro.org>
Reported-by: Riscure <b5f9fc9e60751b217b3b089dcbd74cd514b67618@riscure.com>
Reported-by: Alyssa Milburn <a5c5029f43bc9836f7af03c99377ded51f71ff9b@vu.nl>
Acked-by: Etienne Carriere <f21bc5b8f3ea1962eb45af359f1abea6578cab94@linaro.org>

pascal-brand-st-dev/optee_os,pascal-brand-st-dev/optee_os,pascal-brand-st-dev/optee_os,pascal-brand-st-dev/optee_os,pascal-brand-st-dev/optee_os