forked from Mirrors/opensbi

Currently, there is no sanity check for firmware event code. We don't see any issue as Linux kernel driver does a bound check on firmware events already. However, OpenSBI can't assume sane supervisor mode software always. Thus, an invalid event idx can cause a buffer overflow error. For hardware events, the match will fail for invalid event code anyways. However, a search is unecessary if event code is invalid. Add a event ID validation function to solve the issue. Signed-off-by: Atish Patra <atishp@rivosinc.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Reviewed-by: Anup Patel <anup@brainfault.org>