diff --git a/qemu/target/arm/cpu.h b/qemu/target/arm/cpu.h index 33b07c72..4b1e2541 100644 --- a/qemu/target/arm/cpu.h +++ b/qemu/target/arm/cpu.h @@ -1475,6 +1475,8 @@ FIELD(V7M_CCR, STKOFHFNMIGN, 10, 1) FIELD(V7M_CCR, DC, 16, 1) FIELD(V7M_CCR, IC, 17, 1) FIELD(V7M_CCR, BP, 18, 1) +FIELD(V7M_CCR, LOB, 19, 1) +FIELD(V7M_CCR, TRD, 20, 1) /* V7M SCR bits */ FIELD(V7M_SCR, SLEEPONEXIT, 1, 1) diff --git a/qemu/target/arm/m_helper.c b/qemu/target/arm/m_helper.c index b75c982e..e943c98b 100644 --- a/qemu/target/arm/m_helper.c +++ b/qemu/target/arm/m_helper.c @@ -1930,6 +1930,64 @@ static bool v7m_read_half_insn(ARMCPU *cpu, ARMMMUIdx mmu_idx, return true; } +static bool v7m_read_sg_stack_word(ARMCPU *cpu, ARMMMUIdx mmu_idx, + uint32_t addr, uint32_t *spdata) +{ + /* + * Read a word of data from the stack for the SG instruction, + * writing the value into *spdata. If the load succeeds, return + * true; otherwise pend an appropriate exception and return false. + * (We can't use data load helpers here that throw an exception + * because of the context we're called in, which is halfway through + * arm_v7m_cpu_do_interrupt().) + */ + CPUState *cs = CPU(cpu); + CPUARMState *env = &cpu->env; + MemTxAttrs attrs = {}; + MemTxResult txres; + target_ulong page_size; + hwaddr physaddr; + int prot; + ARMMMUFaultInfo fi = {}; + ARMCacheAttrs cacheattrs = {}; + uint32_t value; + + if (get_phys_addr(env, addr, MMU_DATA_LOAD, mmu_idx, &physaddr, + &attrs, &prot, &page_size, &fi, &cacheattrs)) { + /* MPU/SAU lookup failed */ + if (fi.type == ARMFault_QEMU_SFault) { + qemu_log_mask(CPU_LOG_INT, + "...SecureFault during stack word read\n"); + env->v7m.sfsr |= R_V7M_SFSR_AUVIOL_MASK | R_V7M_SFSR_SFARVALID_MASK; + env->v7m.sfar = addr; + //armv7m_nvic_set_pending(env->nvic, ARMV7M_EXCP_SECURE, false); + } else { + qemu_log_mask(CPU_LOG_INT, + "...MemManageFault during stack word read\n"); + env->v7m.cfsr[M_REG_S] |= R_V7M_CFSR_DACCVIOL_MASK | + R_V7M_CFSR_MMARVALID_MASK; + env->v7m.mmfar[M_REG_S] = addr; + //armv7m_nvic_set_pending(env->nvic, ARMV7M_EXCP_MEM, false); + } + return false; + } + value = address_space_ldl(arm_addressspace(cs, attrs), physaddr, + attrs, &txres); + if (txres != MEMTX_OK) { + /* BusFault trying to read the data */ + qemu_log_mask(CPU_LOG_INT, + "...BusFault during stack word read\n"); + env->v7m.cfsr[M_REG_NS] |= + (R_V7M_CFSR_PRECISERR_MASK | R_V7M_CFSR_BFARVALID_MASK); + env->v7m.bfar = addr; + //armv7m_nvic_set_pending(env->nvic, ARMV7M_EXCP_BUS, false); + return false; + } + + *spdata = value; + return true; +} + static bool v7m_handle_execute_nsc(ARMCPU *cpu) { /* @@ -1986,6 +2044,34 @@ static bool v7m_handle_execute_nsc(ARMCPU *cpu) */ qemu_log_mask(CPU_LOG_INT, "...really an SG instruction at 0x%08" PRIx32 ", executing it\n", env->regs[15]); + + if (cpu_isar_feature(aa32_m_sec_state, cpu) && + !arm_v7m_is_handler_mode(env)) { + /* + * v8.1M exception stack frame integrity check. Note that we + * must perform the memory access even if CCR_S.TRD is zero + * and we aren't going to check what the data loaded is. + */ + uint32_t spdata, sp; + + /* + * We know we are currently NS, so the S stack pointers must be + * in other_ss_{psp,msp}, not in regs[13]/other_sp. + */ + sp = v7m_using_psp(env) ? env->v7m.other_ss_psp : env->v7m.other_ss_msp; + if (!v7m_read_sg_stack_word(cpu, mmu_idx, sp, &spdata)) { + /* Stack access failed and an exception has been pended */ + return false; + } + + if (env->v7m.ccr[M_REG_S] & R_V7M_CCR_TRD_MASK) { + if (((spdata & ~1) == 0xfefa125a) || + !(env->v7m.control[M_REG_S] & 1)) { + goto gen_invep; + } + } + } + env->regs[14] &= ~1; env->v7m.control[M_REG_S] &= ~R_V7M_CONTROL_SFPA_MASK; switch_v7m_security_state(env, true);