diff options
Diffstat (limited to 'lib/cpus/aarch64')
-rw-r--r-- | lib/cpus/aarch64/cortex_a73.S | 5 | ||||
-rw-r--r-- | lib/cpus/aarch64/cortex_a75.S | 10 | ||||
-rw-r--r-- | lib/cpus/aarch64/workaround_cve_2017_5715_bpiall.S | 372 |
3 files changed, 377 insertions, 10 deletions
diff --git a/lib/cpus/aarch64/cortex_a73.S b/lib/cpus/aarch64/cortex_a73.S index 34414c2b..11680a09 100644 --- a/lib/cpus/aarch64/cortex_a73.S +++ b/lib/cpus/aarch64/cortex_a73.S @@ -36,6 +36,11 @@ func cortex_a73_disable_smp endfunc cortex_a73_disable_smp func cortex_a73_reset_func +#if IMAGE_BL31 && WORKAROUND_CVE_2017_5715 + adr x0, workaround_bpiall_vbar0_runtime_exceptions + msr vbar_el3, x0 +#endif + /* --------------------------------------------- * Enable the SMP bit. * Clobbers : x0 diff --git a/lib/cpus/aarch64/cortex_a75.S b/lib/cpus/aarch64/cortex_a75.S index 3825ae47..de1cfda4 100644 --- a/lib/cpus/aarch64/cortex_a75.S +++ b/lib/cpus/aarch64/cortex_a75.S @@ -111,18 +111,8 @@ endfunc cortex_a75_amu_write_cpuamcntenclr_el0 func cortex_a75_reset_func #if IMAGE_BL31 && WORKAROUND_CVE_2017_5715 - mrs x0, id_aa64pfr0_el1 - ubfx x0, x0, #ID_AA64PFR0_CSV2_SHIFT, #ID_AA64PFR0_CSV2_LENGTH - /* - * If the field equals to 1 then branch targets trained in one - * context cannot affect speculative execution in a different context. - */ - cmp x0, #1 - beq 1f - adr x0, workaround_bpiall_vbar0_runtime_exceptions msr vbar_el3, x0 -1: #endif #if ENABLE_AMU diff --git a/lib/cpus/aarch64/workaround_cve_2017_5715_bpiall.S b/lib/cpus/aarch64/workaround_cve_2017_5715_bpiall.S new file mode 100644 index 00000000..cd29266e --- /dev/null +++ b/lib/cpus/aarch64/workaround_cve_2017_5715_bpiall.S @@ -0,0 +1,372 @@ +/* + * Copyright (c) 2017, ARM Limited and Contributors. All rights reserved. + * + * SPDX-License-Identifier: BSD-3-Clause + */ + +#include <arch.h> +#include <asm_macros.S> +#include <context.h> + + .globl workaround_bpiall_vbar0_runtime_exceptions + +#define EMIT_BPIALL 0xee070fd5 +#define EMIT_MOV_R0_IMM(v) 0xe3a0000##v +#define EMIT_SMC 0xe1600070 + + .macro enter_workaround _stub_name + /* Save GP regs */ + stp x0, x1, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X0] + stp x2, x3, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X2] + stp x4, x5, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X4] + stp x6, x7, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X6] + stp x8, x9, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X8] + stp x10, x11, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X10] + stp x12, x13, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X12] + stp x14, x15, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X14] + stp x16, x17, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X16] + stp x18, x19, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X18] + stp x20, x21, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X20] + stp x22, x23, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X22] + stp x24, x25, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X24] + stp x26, x27, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X26] + stp x28, x29, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X28] + + adr x4, \_stub_name + + /* + * Load SPSR_EL3 and VBAR_EL3. SPSR_EL3 is set up to have + * all interrupts masked in preparation to running the workaround + * stub in S-EL1. VBAR_EL3 points to the vector table that + * will handle the SMC back from the workaround stub. + */ + ldp x0, x1, [x4, #0] + + /* + * Load SCTLR_EL1 and ELR_EL3. SCTLR_EL1 is configured to disable + * the MMU in S-EL1. ELR_EL3 points to the appropriate stub in S-EL1. + */ + ldp x2, x3, [x4, #16] + + mrs x4, scr_el3 + mrs x5, spsr_el3 + mrs x6, elr_el3 + mrs x7, sctlr_el1 + mrs x8, esr_el3 + + /* Preserve system registers in the workaround context */ + stp x4, x5, [sp, #CTX_CVE_2017_5715_OFFSET + CTX_CVE_2017_5715_QUAD0] + stp x6, x7, [sp, #CTX_CVE_2017_5715_OFFSET + CTX_CVE_2017_5715_QUAD2] + stp x8, x30, [sp, #CTX_CVE_2017_5715_OFFSET + CTX_CVE_2017_5715_QUAD4] + + /* + * Setting SCR_EL3 to all zeroes means that the NS, RW + * and SMD bits are configured as expected. + */ + msr scr_el3, xzr + + /* + * Reload system registers with the crafted values + * in preparation for entry in S-EL1. + */ + msr spsr_el3, x0 + msr vbar_el3, x1 + msr sctlr_el1, x2 + msr elr_el3, x3 + + eret + .endm + + /* --------------------------------------------------------------------- + * This vector table is used at runtime to enter the workaround at + * AArch32 S-EL1 for Sync/IRQ/FIQ/SError exceptions. If the workaround + * is not enabled, the existing runtime exception vector table is used. + * --------------------------------------------------------------------- + */ +vector_base workaround_bpiall_vbar0_runtime_exceptions + + /* --------------------------------------------------------------------- + * Current EL with SP_EL0 : 0x0 - 0x200 + * --------------------------------------------------------------------- + */ +vector_entry workaround_bpiall_vbar0_sync_exception_sp_el0 + b sync_exception_sp_el0 + /* + * Since each vector table entry is 128 bytes, we can store the + * stub context in the unused space to minimize memory footprint. + */ +aarch32_stub_smc: + .word EMIT_BPIALL + .word EMIT_MOV_R0_IMM(1) + .word EMIT_SMC +aarch32_stub_ctx_smc: + /* Mask all interrupts and set AArch32 Supervisor mode */ + .quad (SPSR_AIF_MASK << SPSR_AIF_SHIFT | \ + SPSR_M_AARCH32 << SPSR_M_SHIFT | \ + MODE32_svc << MODE32_SHIFT) + + /* + * VBAR_EL3 points to vbar1 which is the vector table + * used while the workaround is executing. + */ + .quad workaround_bpiall_vbar1_runtime_exceptions + + /* Setup SCTLR_EL1 with MMU off and I$ on */ + .quad SCTLR_AARCH32_EL1_RES1 | SCTLR_I_BIT + + /* ELR_EL3 is setup to point to the sync exception stub in AArch32 */ + .quad aarch32_stub_smc + check_vector_size workaround_bpiall_vbar0_sync_exception_sp_el0 + +vector_entry workaround_bpiall_vbar0_irq_sp_el0 + b irq_sp_el0 +aarch32_stub_irq: + .word EMIT_BPIALL + .word EMIT_MOV_R0_IMM(2) + .word EMIT_SMC +aarch32_stub_ctx_irq: + .quad (SPSR_AIF_MASK << SPSR_AIF_SHIFT | \ + SPSR_M_AARCH32 << SPSR_M_SHIFT | \ + MODE32_svc << MODE32_SHIFT) + .quad workaround_bpiall_vbar1_runtime_exceptions + .quad SCTLR_AARCH32_EL1_RES1 | SCTLR_I_BIT + .quad aarch32_stub_irq + check_vector_size workaround_bpiall_vbar0_irq_sp_el0 + +vector_entry workaround_bpiall_vbar0_fiq_sp_el0 + b fiq_sp_el0 +aarch32_stub_fiq: + .word EMIT_BPIALL + .word EMIT_MOV_R0_IMM(4) + .word EMIT_SMC +aarch32_stub_ctx_fiq: + .quad (SPSR_AIF_MASK << SPSR_AIF_SHIFT | \ + SPSR_M_AARCH32 << SPSR_M_SHIFT | \ + MODE32_svc << MODE32_SHIFT) + .quad workaround_bpiall_vbar1_runtime_exceptions + .quad SCTLR_AARCH32_EL1_RES1 | SCTLR_I_BIT + .quad aarch32_stub_fiq + check_vector_size workaround_bpiall_vbar0_fiq_sp_el0 + +vector_entry workaround_bpiall_vbar0_serror_sp_el0 + b serror_sp_el0 +aarch32_stub_serror: + .word EMIT_BPIALL + .word EMIT_MOV_R0_IMM(8) + .word EMIT_SMC +aarch32_stub_ctx_serror: + .quad (SPSR_AIF_MASK << SPSR_AIF_SHIFT | \ + SPSR_M_AARCH32 << SPSR_M_SHIFT | \ + MODE32_svc << MODE32_SHIFT) + .quad workaround_bpiall_vbar1_runtime_exceptions + .quad SCTLR_AARCH32_EL1_RES1 | SCTLR_I_BIT + .quad aarch32_stub_serror + check_vector_size workaround_bpiall_vbar0_serror_sp_el0 + + /* --------------------------------------------------------------------- + * Current EL with SP_ELx: 0x200 - 0x400 + * --------------------------------------------------------------------- + */ +vector_entry workaround_bpiall_vbar0_sync_exception_sp_elx + b sync_exception_sp_elx + check_vector_size workaround_bpiall_vbar0_sync_exception_sp_elx + +vector_entry workaround_bpiall_vbar0_irq_sp_elx + b irq_sp_elx + check_vector_size workaround_bpiall_vbar0_irq_sp_elx + +vector_entry workaround_bpiall_vbar0_fiq_sp_elx + b fiq_sp_elx + check_vector_size workaround_bpiall_vbar0_fiq_sp_elx + +vector_entry workaround_bpiall_vbar0_serror_sp_elx + b serror_sp_elx + check_vector_size workaround_bpiall_vbar0_serror_sp_elx + + /* --------------------------------------------------------------------- + * Lower EL using AArch64 : 0x400 - 0x600 + * --------------------------------------------------------------------- + */ +vector_entry workaround_bpiall_vbar0_sync_exception_aarch64 + enter_workaround aarch32_stub_ctx_smc + check_vector_size workaround_bpiall_vbar0_sync_exception_aarch64 + +vector_entry workaround_bpiall_vbar0_irq_aarch64 + enter_workaround aarch32_stub_ctx_irq + check_vector_size workaround_bpiall_vbar0_irq_aarch64 + +vector_entry workaround_bpiall_vbar0_fiq_aarch64 + enter_workaround aarch32_stub_ctx_fiq + check_vector_size workaround_bpiall_vbar0_fiq_aarch64 + +vector_entry workaround_bpiall_vbar0_serror_aarch64 + enter_workaround aarch32_stub_ctx_serror + check_vector_size workaround_bpiall_vbar0_serror_aarch64 + + /* --------------------------------------------------------------------- + * Lower EL using AArch32 : 0x600 - 0x800 + * --------------------------------------------------------------------- + */ +vector_entry workaround_bpiall_vbar0_sync_exception_aarch32 + enter_workaround aarch32_stub_ctx_smc + check_vector_size workaround_bpiall_vbar0_sync_exception_aarch32 + +vector_entry workaround_bpiall_vbar0_irq_aarch32 + enter_workaround aarch32_stub_ctx_irq + check_vector_size workaround_bpiall_vbar0_irq_aarch32 + +vector_entry workaround_bpiall_vbar0_fiq_aarch32 + enter_workaround aarch32_stub_ctx_fiq + check_vector_size workaround_bpiall_vbar0_fiq_aarch32 + +vector_entry workaround_bpiall_vbar0_serror_aarch32 + enter_workaround aarch32_stub_ctx_serror + check_vector_size workaround_bpiall_vbar0_serror_aarch32 + + /* --------------------------------------------------------------------- + * This vector table is used while the workaround is executing. It + * installs a simple SMC handler to allow the Sync/IRQ/FIQ/SError + * workaround stubs to enter EL3 from S-EL1. It restores the previous + * EL3 state before proceeding with the normal runtime exception vector. + * --------------------------------------------------------------------- + */ +vector_base workaround_bpiall_vbar1_runtime_exceptions + + /* --------------------------------------------------------------------- + * Current EL with SP_EL0 : 0x0 - 0x200 (UNUSED) + * --------------------------------------------------------------------- + */ +vector_entry workaround_bpiall_vbar1_sync_exception_sp_el0 + b report_unhandled_exception + check_vector_size workaround_bpiall_vbar1_sync_exception_sp_el0 + +vector_entry workaround_bpiall_vbar1_irq_sp_el0 + b report_unhandled_interrupt + check_vector_size workaround_bpiall_vbar1_irq_sp_el0 + +vector_entry workaround_bpiall_vbar1_fiq_sp_el0 + b report_unhandled_interrupt + check_vector_size workaround_bpiall_vbar1_fiq_sp_el0 + +vector_entry workaround_bpiall_vbar1_serror_sp_el0 + b report_unhandled_exception + check_vector_size workaround_bpiall_vbar1_serror_sp_el0 + + /* --------------------------------------------------------------------- + * Current EL with SP_ELx: 0x200 - 0x400 (UNUSED) + * --------------------------------------------------------------------- + */ +vector_entry workaround_bpiall_vbar1_sync_exception_sp_elx + b report_unhandled_exception + check_vector_size workaround_bpiall_vbar1_sync_exception_sp_elx + +vector_entry workaround_bpiall_vbar1_irq_sp_elx + b report_unhandled_interrupt + check_vector_size workaround_bpiall_vbar1_irq_sp_elx + +vector_entry workaround_bpiall_vbar1_fiq_sp_elx + b report_unhandled_interrupt + check_vector_size workaround_bpiall_vbar1_fiq_sp_elx + +vector_entry workaround_bpiall_vbar1_serror_sp_elx + b report_unhandled_exception + check_vector_size workaround_bpiall_vbar1_serror_sp_elx + + /* --------------------------------------------------------------------- + * Lower EL using AArch64 : 0x400 - 0x600 (UNUSED) + * --------------------------------------------------------------------- + */ +vector_entry workaround_bpiall_vbar1_sync_exception_aarch64 + b report_unhandled_exception + check_vector_size workaround_bpiall_vbar1_sync_exception_aarch64 + +vector_entry workaround_bpiall_vbar1_irq_aarch64 + b report_unhandled_interrupt + check_vector_size workaround_bpiall_vbar1_irq_aarch64 + +vector_entry workaround_bpiall_vbar1_fiq_aarch64 + b report_unhandled_interrupt + check_vector_size workaround_bpiall_vbar1_fiq_aarch64 + +vector_entry workaround_bpiall_vbar1_serror_aarch64 + b report_unhandled_exception + check_vector_size workaround_bpiall_vbar1_serror_aarch64 + + /* --------------------------------------------------------------------- + * Lower EL using AArch32 : 0x600 - 0x800 + * --------------------------------------------------------------------- + */ +vector_entry workaround_bpiall_vbar1_sync_exception_aarch32 + /* Restore register state from the workaround context */ + ldp x2, x3, [sp, #CTX_CVE_2017_5715_OFFSET + CTX_CVE_2017_5715_QUAD0] + ldp x4, x5, [sp, #CTX_CVE_2017_5715_OFFSET + CTX_CVE_2017_5715_QUAD2] + ldp x6, x30, [sp, #CTX_CVE_2017_5715_OFFSET + CTX_CVE_2017_5715_QUAD4] + + /* Apply the restored system register state */ + msr scr_el3, x2 + msr spsr_el3, x3 + msr elr_el3, x4 + msr sctlr_el1, x5 + msr esr_el3, x6 + + /* + * Workaround is complete, so swap VBAR_EL3 to point + * to workaround entry table in preparation for subsequent + * Sync/IRQ/FIQ/SError exceptions. + */ + adr x2, workaround_bpiall_vbar0_runtime_exceptions + msr vbar_el3, x2 + + /* + * Restore all GP regs except x0 and x1. The value in x0 + * indicates the type of the original exception. + */ + ldp x2, x3, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X2] + ldp x4, x5, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X4] + ldp x6, x7, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X6] + ldp x8, x9, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X8] + ldp x10, x11, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X10] + ldp x12, x13, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X12] + ldp x14, x15, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X14] + ldp x16, x17, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X16] + ldp x18, x19, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X18] + ldp x20, x21, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X20] + ldp x22, x23, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X22] + ldp x24, x25, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X24] + ldp x26, x27, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X26] + ldp x28, x29, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X28] + + /* + * Each of these handlers will first restore x0 and x1 from + * the context and the branch to the common implementation for + * each of the exception types. + */ + tbnz x0, #1, workaround_bpiall_vbar1_irq + tbnz x0, #2, workaround_bpiall_vbar1_fiq + tbnz x0, #3, workaround_bpiall_vbar1_serror + + /* Fallthrough case for Sync exception */ + ldp x0, x1, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X0] + b sync_exception_aarch64 + check_vector_size workaround_bpiall_vbar1_sync_exception_aarch32 + +vector_entry workaround_bpiall_vbar1_irq_aarch32 + b report_unhandled_interrupt +workaround_bpiall_vbar1_irq: + ldp x0, x1, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X0] + b irq_aarch64 + check_vector_size workaround_bpiall_vbar1_irq_aarch32 + +vector_entry workaround_bpiall_vbar1_fiq_aarch32 + b report_unhandled_interrupt +workaround_bpiall_vbar1_fiq: + ldp x0, x1, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X0] + b fiq_aarch64 + check_vector_size workaround_bpiall_vbar1_fiq_aarch32 + +vector_entry workaround_bpiall_vbar1_serror_aarch32 + b report_unhandled_exception +workaround_bpiall_vbar1_serror: + ldp x0, x1, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X0] + b serror_aarch64 + check_vector_size workaround_bpiall_vbar1_serror_aarch32 |