According to userspace settings, pointer authentication cpufeature is enabled/disabled from guests.
Signed-off-by: Amit Daniel Kachhap <[email protected]> Cc: Mark Rutland <[email protected]> Cc: Christoffer Dall <[email protected]> Cc: Marc Zyngier <[email protected]> Cc: [email protected] --- arch/arm64/kvm/sys_regs.c | 33 +++++++++++++++++++++------------ 1 file changed, 21 insertions(+), 12 deletions(-) diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index 6af6c7d..ce6144a 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -1055,7 +1055,7 @@ static bool access_cntp_cval(struct kvm_vcpu *vcpu, } /* Read a sanitised cpufeature ID register by sys_reg_desc */ -static u64 read_id_reg(struct sys_reg_desc const *r, bool raz) +static u64 read_id_reg(struct kvm_vcpu *vcpu, struct sys_reg_desc const *r, bool raz) { u32 id = sys_reg((u32)r->Op0, (u32)r->Op1, (u32)r->CRn, (u32)r->CRm, (u32)r->Op2); @@ -1066,6 +1066,15 @@ static u64 read_id_reg(struct sys_reg_desc const *r, bool raz) kvm_debug("SVE unsupported for guests, suppressing\n"); val &= ~(0xfUL << ID_AA64PFR0_SVE_SHIFT); + } else if (id == SYS_ID_AA64ISAR1_EL1) { + const u64 ptrauth_mask = (0xfUL << ID_AA64ISAR1_APA_SHIFT) | + (0xfUL << ID_AA64ISAR1_API_SHIFT) | + (0xfUL << ID_AA64ISAR1_GPA_SHIFT) | + (0xfUL << ID_AA64ISAR1_GPI_SHIFT); + if (!kvm_arm_vcpu_ptrauth_allowed(vcpu)) { + kvm_debug("ptrauth unsupported for guests, suppressing\n"); + val &= ~ptrauth_mask; + } } else if (id == SYS_ID_AA64MMFR1_EL1) { if (val & (0xfUL << ID_AA64MMFR1_LOR_SHIFT)) kvm_debug("LORegions unsupported for guests, suppressing\n"); @@ -1086,7 +1095,7 @@ static bool __access_id_reg(struct kvm_vcpu *vcpu, if (p->is_write) return write_to_read_only(vcpu, p, r); - p->regval = read_id_reg(r, raz); + p->regval = read_id_reg(vcpu, r, raz); return true; } @@ -1115,17 +1124,17 @@ static u64 sys_reg_to_index(const struct sys_reg_desc *reg); * are stored, and for set_id_reg() we don't allow the effective value * to be changed. */ -static int __get_id_reg(const struct sys_reg_desc *rd, void __user *uaddr, - bool raz) +static int __get_id_reg(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd, + void __user *uaddr, bool raz) { const u64 id = sys_reg_to_index(rd); - const u64 val = read_id_reg(rd, raz); + const u64 val = read_id_reg(vcpu, rd, raz); return reg_to_user(uaddr, &val, id); } -static int __set_id_reg(const struct sys_reg_desc *rd, void __user *uaddr, - bool raz) +static int __set_id_reg(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd, + void __user *uaddr, bool raz) { const u64 id = sys_reg_to_index(rd); int err; @@ -1136,7 +1145,7 @@ static int __set_id_reg(const struct sys_reg_desc *rd, void __user *uaddr, return err; /* This is what we mean by invariant: you can't change it. */ - if (val != read_id_reg(rd, raz)) + if (val != read_id_reg(vcpu, rd, raz)) return -EINVAL; return 0; @@ -1145,25 +1154,25 @@ static int __set_id_reg(const struct sys_reg_desc *rd, void __user *uaddr, static int get_id_reg(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd, const struct kvm_one_reg *reg, void __user *uaddr) { - return __get_id_reg(rd, uaddr, false); + return __get_id_reg(vcpu, rd, uaddr, false); } static int set_id_reg(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd, const struct kvm_one_reg *reg, void __user *uaddr) { - return __set_id_reg(rd, uaddr, false); + return __set_id_reg(vcpu, rd, uaddr, false); } static int get_raz_id_reg(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd, const struct kvm_one_reg *reg, void __user *uaddr) { - return __get_id_reg(rd, uaddr, true); + return __get_id_reg(vcpu, rd, uaddr, true); } static int set_raz_id_reg(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd, const struct kvm_one_reg *reg, void __user *uaddr) { - return __set_id_reg(rd, uaddr, true); + return __set_id_reg(vcpu, rd, uaddr, true); } /* sys_reg_desc initialiser for known cpufeature ID registers */ -- 2.7.4 _______________________________________________ kvmarm mailing list [email protected] https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
