lib: sbi_hart: reset sstateen and hstateen

Not resetting sstateen is a potential security hole, because U might be
able to access state that S does not properly context-switch.
Similar for hstateen with VS and HS.

Reviewed-by: Anup Patel <anup@brainfault.org>
Signed-off-by: Radim Krčmář <rkrcmar@ventanamicro.com>
Link: https://lore.kernel.org/r/20250429142549.3673976-6-rkrcmar@ventanamicro.com
Signed-off-by: Anup Patel <anup@brainfault.org>
This commit is contained in:
Radim Krčmář
2025-04-29 16:25:46 +02:00
committed by Anup Patel
parent 009f77a9f0
commit 6b877fb53b

View File

@@ -111,6 +111,12 @@ static void mstatus_init(struct sbi_scratch *scratch)
mstateen_val &= ~SMSTATEEN0_CTR; mstateen_val &= ~SMSTATEEN0_CTR;
csr_write64(CSR_MSTATEEN0, mstateen_val); csr_write64(CSR_MSTATEEN0, mstateen_val);
if (misa_extension('S'))
csr_write(CSR_SSTATEEN0, 0);
if (misa_extension('H'))
csr_write64(CSR_HSTATEEN0, (uint64_t)0);
} }
if (sbi_hart_priv_version(scratch) >= SBI_HART_PRIV_VER_1_12) { if (sbi_hart_priv_version(scratch) >= SBI_HART_PRIV_VER_1_12) {